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PINEY RUN STREAM RESTORATION, CARROLL COUNTY,
MARYLAND: PROJECT SUMMARY AND DESIGN REPORT
By: John B. Hutzell, Kathleen Cullen, and Richard R. Starr
Stream Habitat Assessment and Restoration Program
U.S. Fish and Wildlife Service
Chesapeake Bay Field Office
CBFO – S17 - 01
Annapolis, MD
March 2017
Piney Run Stream Restoration: Project Summary and Design Report
U. S. Fish and Wildlife Service March 2017
Chesapeake Bay Field Office Page | i
TABLE OF CONTENTS
I. INTRODUCTION.................................................................................................................1
II. SITE SELECTION ...............................................................................................................1
III. PROJECT PROCESS METHODOLOGY ........................................................................2
A. Project Process ............................................................................................................................................. 2 B. Watershed Assessment ................................................................................................................................ 4 C. Reach Level Assessment ............................................................................................................................. 4
IV. PROGRAMMATIC / PROJECT GOALS .........................................................................5
V. WATERSHED ASSESSMENT ...........................................................................................5
A. Watershed Assessment Piney Run Mainstem .............................................................................................. 6 B. Watershed Assessment UT6 ........................................................................................................................ 8 C. Watershed Assessment UT6a ...................................................................................................................... 9
VI. REACH LEVEL ASSESSMENT ......................................................................................10
A. Function Based Rapid Assessment Table .................................................................................................. 10 1. Overall Existing Condition ............................................................................................................. 11 2. Level 2 – Hydraulics ....................................................................................................................... 12 3. Level 3 - Geomorphology ............................................................................................................... 12 4. Level 4 - Physicochemical .............................................................................................................. 13 5. Level 5 - Biology ............................................................................................................................ 14
B. Channel Evolution ..................................................................................................................................... 17 C. Level 3 Detailed Assessment Reaches ....................................................................................................... 17
1. Representative Reach - Piney Run .................................................................................................. 19 2. Representative Reach - UT6 Upper ................................................................................................ 21 3. Representative Reach - UT6 Middle ............................................................................................... 23 4. Representative Reach - UT6 Lower ................................................................................................ 25 5. Representative Reach - UT6a Lower .............................................................................................. 27 6. Biology ............................................................................................................................................ 29
VII. WETLAND ASSESSMENT ..............................................................................................30
VIII. DESIGN DEVELOPMENT ...............................................................................................32
A. Project Area Delineation ............................................................................................................................ 32 B. Constraints ................................................................................................................................................. 33 C. Restoration Potential .................................................................................................................................. 34 D. Design Objectives ...................................................................................................................................... 35 E. Design Alternatives Analysis ..................................................................................................................... 36
1. Potential Design Alternatives .......................................................................................................... 37 2. Design Alternatives Analysis .......................................................................................................... 38
a. Sediment Supply ..................................................................................................................................... 38 b. Stream Energy ......................................................................................................................................... 39 c. Floodplain Characteristics ....................................................................................................................... 39 d. Stream Channel Characteristics ............................................................................................................... 40
3. Preferred Plan .................................................................................................................................. 42 a. Potential Functional Uplift ...................................................................................................................... 42 b. Potential Adverse Impacts ....................................................................................................................... 42 c. Uncertainty and Risk ............................................................................................................................... 43 d. Implementation Costs .............................................................................................................................. 45
Piney Run Stream Restoration: Project Summary and Design Report
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F. Design Development ................................................................................................................................. 46 1. Design Criteria ................................................................................................................................ 47 2. Proposed Project Area Descriptions ................................................................................................ 47
a. Project Area 1 .......................................................................................................................................... 47 b. Project Area 2 .......................................................................................................................................... 48 c. Project Area 3 .......................................................................................................................................... 49 d. Project Area 4 .......................................................................................................................................... 50 e. Project Area 5 .......................................................................................................................................... 51 f. Project Area 6 .......................................................................................................................................... 52 g. Project Area 7 .......................................................................................................................................... 53 h. Project Area 8 .......................................................................................................................................... 54 i. Project Area 9 .......................................................................................................................................... 54 j. Project Area 10 ........................................................................................................................................ 55 k. Project Area 11 ........................................................................................................................................ 55 l. Project Area 12 ........................................................................................................................................ 56 m. Project Area 13 ........................................................................................................................................ 57 n. Project Area 14 ........................................................................................................................................ 57 o. Project Area 15 ........................................................................................................................................ 58 p. Project Area 16 ........................................................................................................................................ 59
3. In-stream Structures ........................................................................................................................ 59 a. Cross Vane .............................................................................................................................................. 59 b. J-Hook ..................................................................................................................................................... 60 c. Log Drop Structure .................................................................................................................................. 61 d. Toe Wood ................................................................................................................................................ 62 e. Oxbow/Vernal Pool Features .................................................................................................................. 63 f. Rock/Log Deflector ................................................................................................................................. 63 g. Constructed Riffle ................................................................................................................................... 64 h. Rock Step ................................................................................................................................................ 65 i. Step Pool Channel ................................................................................................................................... 65 j. Stacked Rock Wall .................................................................................................................................. 66 k. Grade Control Woody Riffle ................................................................................................................... 66 l. Ford Stream Crossing .............................................................................................................................. 67 m. Rock Toe ................................................................................................................................................. 67 n. Swale with Ditch Plugs ........................................................................................................................... 67
4. Hydrologic and Hydraulic Analyses ............................................................................................... 68 a. Bankfull Verification ............................................................................................................................... 68
i. Geomorphic Indicators ..................................................................................................................... 68 ii. Regional Relationships .................................................................................................................... 69 iii. Resistance Relationships ................................................................................................................ 69 iv. Bankfull Validation ........................................................................................................................ 73
b. Hydrologic and Hydraulic Assessment ................................................................................................... 73 c. Sediment Analysis ................................................................................................................................... 77
5. Vegetation Design ........................................................................................................................... 78
IX. IMPACTS TO EXISTING RESOURCES .......................................................................79
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LIST OF FIGURES Figure 1: Stream Function Pyramid (Harman et al., 2012) ........................................................................... 3 Figure 2: Stream Functions Pyramid Framework (Harman et al., 2012) ...................................................... 4 Figure 3: Piney Run Watershed and Subwatershed Delineation .................................................................. 6 Figure 4: Function Based Condition of reaches within the Piney Run project area ................................... 11 Figure 5: Representative Reaches with Level 3 Detailed Assessment........................................................ 19 Figure 6: Piney Run MBSS Sampling Site Locations ................................................................................ 29 Figure 7: Piney Run wetland locations identified by MDNR ..................................................................... 31 Figure 8: Project Reach Delineation ........................................................................................................... 32 Figure 9: Project Constraints ...................................................................................................................... 33 Figure 10: Channel formation tool with associated data from Piney Run plotted (Tweedy, K.L., 2008.). 41 Figure 11: Cross Vane in Plan View ........................................................................................................... 60 Figure 12: J-Hook Vane in Plan View ........................................................................................................ 61 Figure 13: Log Drop Structure .................................................................................................................... 62 Figure 14: Toe Wood .................................................................................................................................. 62 Figure 15: Oxbow Creation ........................................................................................................................ 63 Figure 16: Rock Deflector in Plan View ..................................................................................................... 64 Figure 17: Constructed Riffle in Plan View ................................................................................................ 64 Figure 18: Rock Step in Plan View ............................................................................................................. 65 Figure 19: Step Pool Channel in Plan View ............................................................................................... 65 Figure 20: Stacked Rock Wall in Plan View .............................................................................................. 66 Figure 21: Grade Control Woody Riffle in Plan View ............................................................................... 66 Figure 22: Ford Stream Crossing Structure ................................................................................................ 67 Figure 23: Rock Toe Structure .................................................................................................................... 67 Figure 24: Swale with Ditch Plugs in Plan View ........................................................................................ 68 Figure 25: Typical Bankfull Indicators (McCandless, 2003) ...................................................................... 69
LIST OF TABLES Table 1: Piney Run Function Based-Assessment Ratings which include functioning (F), functioning-at-
risk (FAR), and not-functioning (NF). FAR/F indicates transition from functioning-at-risk to functioning
and FAR/NF indicates transition from functioning-at-risk to not functioning. .......................................... 16 Table 2: Piney Run Level 3 Detailed Assessment Reach Distribution ....................................................... 18 Table 3: Piney Run Main Function-based Assessment Table ..................................................................... 20 Table 4: Piney Run Main Channel Evolution Rating.................................................................................. 21 Table 5: UT6 Upper Function-based Assessment Table ............................................................................. 22 Table 6: UT6 Upper Channel Evolution Rating ......................................................................................... 22 Table 7: UT6 Middle Function-based Assessment Table ........................................................................... 24 Table 8: UT6 Middle Channel Evolution Rating ........................................................................................ 25 Table 9: UT6 Lower Function-based Assessment Table ............................................................................ 26 Table 10: UT6 Lower Channel Evolution Rating ....................................................................................... 27 Table 11: UT6a Lower Function-based Assessment Table ........................................................................ 28 Table 12: UT6a Lower Channel Evolution Rating ..................................................................................... 28 Table 13: Piney Run Indices of Biotic Integrity ......................................................................................... 30 Table 14: Piney Run Project Areas 1, 2, 8, 10 - 13 and 16 - Design Objectives ........................................ 35 Table 15: Piney Run Project Areas 3 -7, 9, 14 and 15 - Design Objectives ............................................... 36 Table 16: Design and Regional Curve Bankfull Characteristics ................................................................ 73 Table 17: HEC-RAS Model Results ........................................................................................................... 76 Table 18: Sediment Transport Capacity for Representative Reaches ......................................................... 78 Table 19: Table of Potential Impacts to Existing Resources ...................................................................... 81
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APPENDICES Appendix A. Assessment and Design Review Checklists
Appendix B. Watershed Assessment
Appendix C. Level 3 Representative Reaches Data
Appendix D. DNR MBSS Biology Report
Appendix E. Wetland Assessment
Appendix F. Soil Trench Data
Appendix G. Project Reach Specific Design Criteria
Appendix H. Implementation Costs
Appendix I. Velocity Calculations
Appendix J. HEC-RAS: Existing and Proposed
Appendix K. Planting Plan
Appendix L. Impacts to Existing Resources
Piney Run Stream Restoration: Project Summary and Design Report
U. S. Fish and Wildlife Service March 2017
Chesapeake Bay Field Office Page | 1
I. INTRODUCTION
Maryland Department of Natural Resources (MDNR), Western Maryland Resource Conservation
and Development Council (RC&D) and the U.S. Fish and Wildlife Service (Service) -
Chesapeake Bay Field Office are involved in a collaborative effort to restore stream functions on
a large portion of Piney Run and its tributaries, located in Carroll County, Maryland. This project
is being done to address Total Maximum Daily Load (TMDL) targets put in place by the state of
Maryland and creating suitable habitat for Service trust species.
Piney Run is located in the Chesapeake Bay watershed in Carroll County, Maryland. It flows
southeast 5.5 miles from its source near Salem Bottom Road in Westminster, Maryland before
entering Piney Run Reservoir. The reservoir is approximately 300 acres and was built in 1967 to
serve as flood attenuation and as recreational water to the public. Piney Run exits the reservoir
via drop inlet structure and becomes a tail water stream controlled by the reservoir outfall. It then
flows for another 4.0 miles through the proposed 1,440 acre project area to its confluence with
the Patapsco River, which ultimately enters the Chesapeake Bay. The Piney Run watershed has
been hampered by poor agriculture practices as well as suburban development which has led to
extensive erosion and loss of aquatic habitat. The project area lies within a catchment that is
primarily mixed residential / agriculture land use with approximately 15 percent impervious
surface and 20 percent forested.
This report documents the findings of the function-based watershed assessment, function-based
reach-scale assessment and design development process used by the Service to develop the
restoration plan for the Piney Run Stream Restoration.
II. SITE SELECTION
MDNR approached the Service about the possibility of a large-scale stream restoration project
that would take place entirely on State owned property. MDNR had identified the site as a
priority for TMDL reduction, since changes could be made on a watershed scale in some of the
tributaries to Piney Run. The project site also aligned with Service priorities of improving habitat
for certain Federal Trust species. The Service conducted a rapid assessment on approximately 9
miles of stream within the project area to determine the restoration potential. Restoration
potential is the highest level of restoration or functional lift that can be achieved given the site
constraints and health of the watershed. Many reaches throughout the proposed project area have
been impacted by agriculture practices, which have led to unstable stream banks, disconnected
floodplains, poor bedform diversity, and little to no riparian vegetation or buffer. However, the
Service and MDNR felt that many of these functions could be restored, providing benefits for
habitat, as well as water quality.
Given the restoration potential, the Service felt that the proposed site is an excellent candidate for
stream restoration.
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III. PROJECT PROCESS METHODOLOGY
A. PROJECT PROCESS
The Service used the “Function-based Stream Restoration Project Process Guidelines” (Starr et
al., 2016) in developing the most appropriate design approach for the proposed project. The
document guides users through the stream restoration process from developing well-articulated
goals and objectives, selecting watershed and reach-level assessment parameters and
measurement methods, conducting design alternatives analysis, developing restoration designs,
and establishing quantifiable and measurable monitoring performance standards. The goal of the
guidelines is to assist permit applicants in selecting and implementing the best project restoration
solution based on watershed health, stressors, constraints, reach-level conditions, restoration
potential, goals and objectives, and other regulatory requirements. The Function-based Stream
Restoration Project Process is comprised of nine sequential steps that create a transparent process
which directly links programmatic goals with design elements to support stream functions. Each
step builds upon the previous step and at each step, programmatic goals and design goals and
objectives are re-evaluated to ensure they can still be achieved.
The SFPF project process consists of the following steps:
Programmatic/Project Goals – Documents what is driving the project and why the project is
being proposed.
Watershed Assessment – Determines the health of the watershed and its influence on the proposed
project area.
Reach-Scale Function-based Assessment – Establishes the existing function-based condition,
determines stressors, identifies constraints, and determines channel functional evolution.
Restoration Potential – Determines the highest level of restoration that can be achieved given the
watershed conditions, function-based assessment results, stressors, and constraints. Also, it is at
this point that the actual amount of potential functional lift will be determined.
Design Objectives – Establishes design objectives based on the project goals, results of the
watershed and reach-scale function-based assessment, constraints, and restoration potential.
Design objectives define how the project is going to be completed.
Design Alternatives Analysis – Determines the restoration design approach that best meets the
project goals, objectives, and restoration potential of the site. The focus is on how a design
approach can change stream functions.
Design Development – Documents the design development process, ensures project feasibility,
determines project implementation costs, and produces a constructible design set along with
specifications and materials.
Monitoring Plan – Determines if the quantifiable project objectives are achieved and that existing
functioning parameters remain functioning.
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The Function-based Stream Restoration Project Process Guidelines were developed following “A
Function-Based Framework for Stream Assessment and Restoration Projects” (Harman et al.,
2012). This document is based on the premise of a hierarchal relationship of stream functions
where lower-level functions support higher-level functions and that they are all influenced by
local geology and climate, which underlies the Pyramid (Figure 1 ). The Pyramid is a broad-level
view of stream functions and consists of five functional categories that evaluate stream functions.
Each category has a functional statement that describes its primary function. The framework that
supports the Pyramid, commonly referred to as the Stream Functions Pyramid Framework
(SFPF) is a “drilling down” approach that provides more detailed forms of analysis and
quantification of stream functions (Figure 2). The function-based assessment parameters describe
and support the functional statements within each functional category. The “measurement
methods” are specific tools, equations, assessment methods, etc. that are used to quantify the
function-based parameter.
Figure 1: Stream Function Pyramid (Harman et al., 2012)
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Figure 2: Stream Functions Pyramid Framework (Harman et al., 2012)
B. WATERSHED ASSESSMENT
The purpose of the watershed assessment is to determine the influence of the watershed health on
the proposed project area. Specifically, watershed characteristics are evaluated to document
hydrology (i.e., flow regime), sediment supply (i.e., sources and amount), water quality (i.e.,
types and sources) and biology (i.e., locations and health). By understanding watershed
conditions, it can be determined if programmatic goals are achievable, as well as the restoration
potential of the project reach.
The watershed assessment involved two levels of assessment: stream-based assessment and land-
based assessment. The stream-based assessment involved a visual assessment of stream
character and stability condition upstream and downstream of the project area. The fluvial
geomorphic conditions observed included channel dimensions, pattern, profile, substrate
material, vertical and lateral stability, sediment supply potential, Rosgen stream type, and
channel evolution. The land-based assessment analyzed land use/land cover patterns, soils,
geology, hydrology, valley type, existing water quality and biological data, and watershed
development.
C. REACH LEVEL ASSESSMENT
The purpose of the reach level function-based assessment is to establish the existing functional
condition, determine stressors, and identify constraints at the proposed project site. The Service
conducted a rapid assessment of all stream reaches within the Piney Run project area and
Broad-Level View (Stream Functions Pyramid)
Function-Based Parameters
Measurement Methods Performance Standards
Functional Categories
Functional Statements
Describes/Supports
Functional Statement
Quantifies Function-Based Parameter Functioning
Functioning-At-Risk
Not Functioning
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detailed function-based assessment at reaches that were representative of the function-based
conditions determined from the rapid assessment. The rapid assessment used the Function-based
Rapid Stream Assessment Protocol (Starr et al., 2015) and the detailed assessment used the
Rosgen Level 3 assessment method. Critical functions on every level of the pyramid were
assessed so that potential changes in functions could be evaluated for each proposed design
alternative. Additionally, critical functions supporting the project goals were assessed.
The following assessment parameters, by pyramid level, were evaluated:
Level 1 - Hydrology – concentrated flows, land use changes, and flashiness (flow regime)
Level 2 - Hydraulics – floodplain connectivity and floodplain drainage
Level 3 - Geomorphology – lateral stability and riparian vegetation
Level 4 - Physicochemical – overall water quality
Level 5 - Biology – macroinvertebrate communities and fish communities
Each assessment parameter had at least one measurement method to quantify the existing
function-based condition. Then, each measurement method value was rated as either functioning
(F), functioning-at-risk (FAR), or not functioning (NF) based on set performance standards.
To simplify plan review for these agencies, the Service has prepared the Function-based Stream
Restoration Project Process Review Checklist (Appendix A – Assessment and Design Review
Checklists).
IV. PROGRAMMATIC / PROJECT GOALS
The programmatic goals of the Piney Run stream restoration project differ among the main
agencies involved with the restoration. The funds for the project were provided by the MDNR,
whose goal is to focus funds on the most cost-effective, innovative approaches within an
efficient and logical location to improve the health of Maryland watershed lands, streams and
non-tidal rivers, as well as to reduce harmful TMDL. The Service’s goals are to create riparian
habitat for Eastern Wood-Peewee, Red-Shoulder Hawk and Acadian Flycatcher; to create
wetland habitat for Spotted Salamander, Gray Tree Frog and Northern Green Frog; and to
improve and preserve downstream habitat for American Eel and other aquatic species through
stream restoration.
The successful completion of the Piney Run stream restoration project will satisfy strategic
objectives put in place by the President Obama’s Chesapeake Bay Initiative, as well as the
Service’s strategic plan for trust species.
V. WATERSHED ASSESSMENT
There are three distinct watersheds that account for most of the water resources found within the
project limits of the Piney Run stream restoration (Figure 3). These watersheds represent the
contributing drainage areas to the main stem of Piney Run, Unnamed Tributary 6, and Unnamed
Piney Run Stream Restoration: Project Summary and Design Report
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Tributary 6a. The Service identified and analyzed each of these watersheds. This section
includes a summary of each of the watersheds however, detailed watershed data can be found in
Appendix B.
Figure 3: Piney Run Watershed and Subwatershed Delineation
A. WATERSHED ASSESSMENT PINEY RUN MAINSTEM
The watershed drainage area is 15.2 sq mi (Figure 3) and lies within the piedmont physiographic
region of Maryland. What is unique about the main stem of Piney Run within the project area is
that a large recreational and water supply reservoir controls the discharges and sediments from
higher in the watershed. Understanding this condition is important because channel dimensions
are developed based on stream flows. If stream flows are over estimated, then there is a potential
for channel design dimensions to be oversized, which could lead to stream instability problems.
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The Piney Run watershed has a flow regime typical of a rural hydrograph, and it is not
considered to be a “flashy” system. The 298-acre Piney Run Reservoir, found upstream of the
project site, has a large influence on the hydraulics of the watershed through its capacity and
controlled discharge. The watershed is approximately 45 percent agricultural, 25 percent
forested, 26 percent development (e.g., residential and commercial), and 15 percent
imperviousness. The shape of the basin is relatively narrow and long and has a slope of
approximately 6.9 percent. The predominant soils are considered moderate to well drained.
Given these watershed characteristics, the watershed flow regime would be considered just on
the edge of non-flashy. The percent of agricultural and imperviousness is just high enough to
start influencing precipitation runoff rates. However, the reservoir does serve as an attenuation
feature which lengthens the hydrograph and reduces the more harmful peak flows. Thus, the
proposed project area has more of a non-flashy flow regime but would likely be considered
flashy if the reservoir was not in place.
Sediment supply being delivered to the project area from the watershed is low to moderate.
While agricultural use represents approximately 45 percent of the watershed, the location of most
agriculture is upstream of the Piney Run Reservoir, limiting its impact. However, prior land use
changes are causing stream bank erosion directly upstream of the project area and, as a result,
increases in sediment supply. Therefore, the project area must be designed in such a way that it
addresses the sediment supply. The design could either transport the sediment, capture the
sediment, or some combination of both. How the sediment will be handled will be addressed
during the design alternatives analysis later in the report.
A 2006 wetland restoration prioritization report completed by MDE provided water quality
information for Piney Run Reservoir and Piney Run. Piney Run and all its tributaries are
considered Use III, natural trout waters. Above Slacks Road, Piney and its tributaries are listed as
Use III-P, natural trout waters and public drinking supply. The 303(b) report of the South Branch
Patapsco watershed noted that Piney Run was unable to support all its designated uses due to
nutrients, low dissolved oxygen, and aquatic plants (MDE, 2006). Piney Run is listed on the
303(b) report as having impaired water quality, due to poor biological community. The MDE
report summarized a water quality analysis for eutrophication in the reservoir, noting that water
quality was not impaired by nutrients (according to use designation requirements), but was
borderline mesotrophic and eutrophic.
Landscape connectivity of the project area plays a role on the ability of a stream restoration
project to result in biological uplift from two perspectives. The first is the stability condition of
upstream reaches. If upstream reaches are stable, then the amount of sediment being delivered to
the site would mostly likely not have adverse impacts. Second, if the upstream, as well as the
downstream reaches, are stable and healthy (meaning they support biological life), then they can
be a source of macroinvertebrates and fish to recolonize the project area. The conditions of
stream reaches upstream and downstream of the project area are fair, and can provide some
source for biological recolonization of the project area.
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B. WATERSHED ASSESSMENT UT6
The watershed drainage area is 2.2 sq mi (Figure 3) and lies within the piedmont physiographic
region of Maryland. The drainage area associated with UT6 is the most impacted by
development and imperviousness in the entire project area.
The Piney Run watershed has a flow regime more typical of an urban hydrograph, and is
considered to be a “flashy” system. The watershed is approximately 67 percent developed, 15
percent forested, 15 percent agriculture and 34 percent imperviousness. Contrary to the Piney
Run watershed, the shape of this basin is nearly as wide as it is long and has a slope of
approximately 7.2 percent. The predominant soils are considered moderate to well drained. The
percent of agricultural and imperviousness is high enough to start influencing precipitation
runoff rates. However, the Carroll County government has begun implementing a number of
stormwater retrofits which have been able to extend the hydrograph and reduce harmful peak
flows. The County plans to continue retrofits in the area.
Sediment supply being delivered to the project area from the watershed is moderate to high. The
Service conducted a brief sediment analysis at three locations upstream of the UT6 project area
and noted moderate to high erosion rates at two of the three sites. Prior land use changes coupled
with development and impervious surfaces are causing stream bank erosion directly upstream of
the project area and, as a result, an increase in sediment supply. Therefore, the project area must
be designed in such a way that it addresses the sediment supply. The design could either
transport the sediment, capture the sediment, or some combination of both. How the sediment
will be handled will be addressed during the design alternatives analysis later in the report.
The water quality being delivered to the project area is fair. While no physical data were
collected, watershed variables such as land use, soils and point and non-point discharges can be
used to predict water quality conditions. The project area watershed is primarily developed, has
highly erodible soils, point source discharges, and a flashy flow regime. Under these conditions
there will be an excessive sediment supply and frequent flooding and drying events which can
cause rapid and adverse changes in pH, dissolved oxygen, conductivity, nitrogen, phosphorus,
siltation levels, and concentrations of ions, toxins or pollutants (Williams, 1996) within the
reach.
Landscape connectivity of the project area plays a role on the ability of a stream restoration
project to result in biological uplift from two perspectives. The first is the stability condition of
upstream reaches. If upstream reaches are stable, then the amount of sediment being delivered to
the site would mostly likely not have adverse impacts. Second, if the upstream, as well as the
downstream reaches, are stable and healthy (meaning they support biological life), then they can
be a source of macroinvertebrates and fish to recolonize the project area. The conditions of
stream reaches upstream and downstream of the project area are fair, and can provide some
source for biological recolonization of the project area.
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U. S. Fish and Wildlife Service March 2017
Chesapeake Bay Field Office Page | 9
C. WATERSHED ASSESSMENT UT6A
The watershed drainage area is 0.8 sq mi (Figure 3) and lies within the piedmont physiographic
region of Maryland. Since UT6a is a sub-watershed of UT6, it is plagued by similar stressors.
The UT6a watershed has a flow regime more typical of an urban hydrograph, and is considered
to be a “flashy” system. The watershed is approximately 67 percent developed, 15 percent
forested, 15 percent agriculture and 38 percent imperviousness. Contrary to the Piney Run
watershed, the shape of this basin is nearly as wide as it is long and has a slope of approximately
8.0 percent. The predominant soils are considered moderate to well drained. The percent of
agricultural and imperviousness is high enough to start influencing precipitation runoff rates.
However, the Carroll County government has begun implementing a number of stormwater
retrofits which have been able to extend the hydrograph and reduce harmful peak flows. The
County plans to continue retrofits in the area.
Sediment supply being delivered to the project area from the watershed is moderate. The Service
conducted a brief sediment analysis at three locations upstream of the UT6a project area and
noted low to moderate erosion rates at two of the three sites. Prior land use changes coupled with
development and impervious surfaces are causing stream bank erosion directly upstream of the
project area and, as a result, increases in sediment supply. Therefore, the project area must be
designed in such a way that it addresses the sediment supply. The design could either transport
the sediment, capture the sediment, or some combination of both. How the sediment will be
handled will be addressed during the design alternatives analysis later in the report.
The water quality being delivered to the project area is fair. While no physical data were
collected, watershed variables such as land use, soils and point and non-point discharges can be
used to predict water quality conditions. The project area watershed is primarily developed, has
highly erodible soils, point source discharges and a flashy flow regime. Under these conditions
there will be an excessive sediment supply and frequent flooding and drying events which can
cause rapid and adverse changes in pH, dissolved oxygen, conductivity, nitrogen, phosphorus,
siltation levels, and concentrations of ions, toxins or pollutants (Williams, 1996) within the
reach.
Landscape connectivity of the project area plays a role on the ability of a stream restoration
project to result in biological uplift from two perspectives. The first is the stability condition of
upstream reaches. If upstream reaches are stable, then the amount of sediment being delivered to
the site would mostly likely not have adverse impacts. Second, if the upstream, as well as the
downstream reaches, are stable and healthy (meaning they support biological life), then they can
be a source of macroinvertebrates and fish to recolonize the project area. The conditions of
stream reaches upstream and downstream of the project area are fair, and can provide some
source for biological recolonization of the project area.
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U. S. Fish and Wildlife Service March 2017
Chesapeake Bay Field Office Page | 10
VI. REACH LEVEL ASSESSMENT
A comprehensive function-based assessment was conducted in all tributaries within the project
site, as well as a BANCS survey to determine bank erosion rates. This information was compiled
and each reach was classified in terms of function. The findings allowed the reaches to be
categorized and helped define areas that could be surveyed in further detail to collect
representative geomorphic data.
While the initial assessment focused on the entire state-owned property, it was decided amongst
partners that the project should be parsed out into two design sections to better serve the
forecasted construction effort. These sections were then referred to Phase 1 and Phase 2. The
remainder of this report focuses on the Phase 1 design area which is the lower portion of Piney
Run watershed below Slacks Road.
A. FUNCTION BASED RAPID ASSESSMENT TABLE
The Service conducted a rapid stream assessment of all stream systems within the project using
the Function-based Rapid Stream Assessment Protocol (Starr et al, 2015), as described in the
Section III-Project Process Methodology.
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Chesapeake Bay Field Office Page | 11
Figure 4: Function Based Condition of reaches within the Piney Run project area
1. Overall Existing Condition
The overall function-based existing conditions of the Piney Run project include functioning (16
reaches), functioning-at-risk (29 reaches), and not functioning (6 reaches) conditions, as shown
in Figure 4 above and Table 1 below. Additionally, there were 22 reaches that have transitionary
conditions including functioning-at-risk to functioning and functioning-at-risk transitioning to
not functioning. Transitionary conditions describe whether reaches are naturally evolving to
either more or less stable conditions. There are 11 reaches that were characterized as undergoing
an overall transition to functioning conditions from functioning-at-risk. These reaches have had a
long enough time frame to adapt to the stress that was placed on the historic channel and have
established a floodplain, grade control and stable plan form to almost be fully stable. Eleven
other reaches were transitioning from functioning-at-risk to not functioning conditions. These
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reaches are undergoing further degradation and are just beginning vertical downcutting and will
take significant time to reach stable conditions naturally.
Overall, the main stem of Piney Run and the unnamed tributaries below Slacks Road have been
significantly impacted by agricultural development in the watershed. Generally, the unnamed
tributaries in the headwaters of the watershed are in the best condition relative to the watershed.
The better overall condition can be linked to the existing forested environment that helps buffer
concentrated runoff, limited channel incision due to bedrock grade controls, and less stream
energy to cause incision due to lower energy gradients. Stream reaches in the middle and lower
portions of the watershed are in generally poorer conditions than the headwater reaches. These
reach conditions are adversely impacted because of their closer proximity to agricultural
development which has increased concentrated flows, and significantly reduced riparian
vegetation that resulted in rapid vertical and lateral stream degradation and adverse impacts to
quality and aquatic species. A description of existing function based conditions is described by
Pyramid Levels 2 through Level 5 below.
2. Level 2 – Hydraulics
Level 2 – Hydraulics is assessed by the streams connectivity to the floodplain. Floodplain
connectivity is measured by the bank height ratio and entrenchment ratio. The bank height ratio
provides a measurement of how quickly stream flows overtop their banks and inundate the
floodplain. The entrenchment ratio then describes the width of the floodplain available for flood
flows to spread out once stream flows have overtopped the banks. The mainstem of Piney Run is
characterized as functioning-at-risk for all assessed reaches. This means that the stream is on
average significantly incised and moderately entrenched, meaning that greater discharge
volumes, with higher associated flow velocities, are required to overtop the banks and inundate
the floodplain. In total, over half of the total length of the project (49 of the 74 assessment
reaches) across Piney Run and its tributaries are described as not functioning or functioning-at-
risk for floodplain connectivity. The remaining 25 assessed reaches had conditions that could be
characterized as functioning in terms of floodplain connectivity. These reaches can access
floodplain areas frequently with smaller discharge flows, and thereby decrease in-stream
discharge velocities which in turn reduces shear stress on banks. The more frequent inundation
of the floodplain also reduces sediment load and helps promote development of wetland
complexes.
3. Level 3 - Geomorphology
Level 3 – Geomorphology is assessed by lateral stability, bedform diversity, sediment transport,
riparian vegetation, and channel evolution. Lateral stability is a measurement of how quickly
banks are eroding and the total extent of bank erosion along the stream. Stabilization of bank
erosion is a primary goal in almost all stream restoration projects. The assessment of bedform
diversity measures variables such as pool-to-pool spacing, pool depth, and shelter for fish. These
measurement methods provide measures to determine if the physical environment required for
natural stream processes and aquatic life are present. Sediment transport then helps evaluate the
stability of the current channel form. Sediment transport stability for a stream determines if
aggradation and degradation forces within the stream reach are in a pseudo-equilibrium. Riparian
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vegetation assesses the quantity and quality of vegetation along the stream banks, which help
promote beneficial stream functions and lateral stability. Finally, channel evolution synthesizes a
variety of assessment parameters to determine how the stream is adjusting to its new
environment and imposed conditions. Results from this section are described in detail in Section
VI.B–Channel Evolution. Reaches that are characterized as functioning have indicators of a
stable stream system including a lack of vertical or lateral adjustments, a developed and
vegetated floodplain, and appropriate floodplain drainage to limit concentrated flows.
Across the Piney Run mainstem and tributary reaches, only approximately one-third (23 of the
74 assessed reaches) of the Piney Run project had functioning conditions for lateral stability.
This means that 51 of the assessment reaches have either localized or widespread bank erosion
caused by the increased flow velocities and shear stresses as suggested in the hydrology and
hydraulics assessments. Bedform diversity is either characterized as functioning-at-risk or not
functioning in 55 of the assessment reaches. The increased stream energy and bank erosion
contribute to poor bedform diversity by straightening the channel and removing meander bends
where deep pools are located. While large woody debris or large rock can lead to the formation
of scour pools in straightened and incised channels, lack of these natural grade control structures
in areas of Piney Run prevents the establishment of natural scour pools to replace meander pools.
Sediment transport (vertical stability) is the next Geomorphology assessment parameter and
approximately one-third (29 of the 74 assessment reaches) of the Piney Run project is
characterized by functioning conditions. While there are areas of extensive bank erosion across
the Piney Run project, the increased flow velocities can transport the sediment through the
reaches and prevent widespread aggradation on the channel bed. Focusing on vertical stability,
channel beds in several reaches are controlled by bedrock to prevent extensive headcuts and
gentler downcutting of the channel bed. Riparian vegetation is the assessment parameter most
often characterized as not functioning, with 28 assessment reaches. Thirty-five assessment
reaches are characterized as functioning-at-risk and a small portion, only 11 assessment reaches,
are characterized as functioning. Encroachment into the natural stream corridor and riparian
buffer that helps manage and mitigate stormwater runoff is one of the common adverse impacts
to stream channels from nearby development. Channel evolution is the final assessment
parameter that combines several pieces of information and 23 of the assessment reaches were
characterized as functioning. The remaining 51 assessment reaches all show evidence of
undergoing some channel adjustments to reach a new stable state with the environment. For
Geomorphology overall, 17 of the 74 assessment reaches can be characterized as functioning, 50
assessment reaches functioning-at-risk, and 7 assessment reaches not functioning.
4. Level 4 - Physicochemical
Level 4 – Physiochemical is assessed by water quality appearance and nutrient levels. The rapid
assessment evaluates qualitative parameters including water clarity, oil sheens, films, and algal
growth. When present, these criteria are signs of untreated runoff entering the stream that can
impair water quality. Only one assessment reach, where flow was mostly a result of concentrated
stormwater runoff, was characterized as having not functioning water quality and nutrients.
Twenty-eight assessment reaches were then characterized to have functioning water quality
conditions while the rest of the 45 assessment reaches were characterized to be functioning-at-
risk. These water quality conditions for Piney Run and its tributaries in the project area are
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typical for a stream that is impacted by increased runoff and a high sediment load. Efforts to
increase water quality must be focused on improvement to the watershed health and decreased
sediment and nutrient loading from untreated runoff.
5. Level 5 - Biology
Level 5 – Biology is assessed by the presence of macroinveterbrates and fish species in the
reach. The rapid assessment evaluates the presence of various species as abundant, rare, or
absent within the stream channel. Eleven assessment reaches were found to have abundant
populations of various species that allow biology to be characterized as functioning. Conversely,
16 of the assessment reaches had a lack of aquatic life that required the biology to be
characterized as not functioning. The presence of healthy populations in certain reaches in the
Piney Run project area suggest that with appropriate uplift to habitat and improvements to water
quality, natural recolonization is possible inside the project.
Stream
Segment
Stream
Reach
Assessment Parameter
Overall
Function-
Based
Condition
Level 2 -
Hydraulics Level 3 - Geomorphology
Level 4 –
Physico-
chemical
Level 5
-
Biology
Floodplain
Connectivity
Lateral
Stability
Bedform
Diversity
Sediment
Transport
(Vertical
Stability)
Channel
Evolution
Trend
Riparian
Vegetation
Overall
Geomorphology
Conditions
Water
Quality and
Nutrients
Presence
Piney
Run
1 FAR FAR FAR FAR FAR FAR FAR FAR FAR FAR
2 FAR/F FAR/F FAR F FAR NF FAR FAR FAR FAR/F
3 FAR
FAR/
NF FAR FAR FAR NF FAR FAR FAR FAR
4 FAR FAR F F FAR NF FAR FAR FAR FAR
5 FAR NF FAR FAR FAR NF FAR FAR FAR FAR/NF
6 FAR FAR FAR FAR FAR NF FAR FAR FAR FAR/F
7 FAR FAR FAR FAR FAR FAR FAR FAR FAR FAR/F
UT1
1 FAR FAR FAR FAR FAR NF FAR NF NF FAR/NF
2 WETLAND COMPLEX
3 FAR FAR FAR FAR NF FAR FAR FAR FAR FAR
4 NF FAR FAR FAR NF NF NF FAR FAR FAR/NF
UT1a 1 F F NF FAR F NF FAR FAR NF FAR/NF
UT2
1 F F FAR F F FAR FAR FAR NF FAR/F
2 FAR FAR FAR F FAR FAR FAR FAR NF FAR/F
3 FAR FAR NF FAR FAR NF FAR FAR NF FAR/F
4 WETLAND COMPLEX F
5 FAR FAR FAR FAR FAR NF FAR FAR NF FAR
6 F FAR F F F FAR F FAR NF F
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7 FAR FAR FAR FAR FAR NF FAR FAR NF FAR
8 FAR NF FAR FAR FAR FAR FAR FAR FAR FAR
9 F F FAR F F FAR F FAR FAR F
10 FAR FAR FAR FAR FAR NF FAR FAR NF NF
UT2a 1
2
UT3
1 WETLAND COMPLEX
2 F F FAR F F NF FAR F FAR FAR
3 FAR FAR FAR FAR FAR NF FAR F FAR FAR/NF
UT3a 1 F F FAR FAR FAR FAR FAR FAR NF FAR/F
UT4
1 FAR FAR NF FAR FAR FAR FAR FAR FAR FAR
2 WETLAND COMPLEX
3 FAR FAR NF NF
FAR/N
F FAR FAR/NF FAR FAR FAR/NF
4 FAR FAR NF NF FAR FAR FAR FAR NF FAR/NF
5 WETLAND COMPLEX
UT5 1 FAR F FAR F F NF FAR FAR FAR FAR/F
UT6
1 F F F F F FAR F F F F
2 FAR FAR F F FAR FAR F F FAR FAR
3 FAR F F FAR FAR F FAR F FAR FAR
4 FAR FAR FAR FAR FAR F FAR F FAR FAR
5 NF NF NF FAR NF F NF F FAR NF
6 F F F F F F F F FAR F
7 F F F F F NF F F FAR F
8 FAR FAR FAR FAR FAR NF FAR FAR FAR FAR
9 NF NF FAR FAR NF FAR NF FAR FAR NF
10 FAR NF FAR FAR FAR NF FAR FAR F FAR/NF
11 FAR FAR FAR FAR FAR NF FAR/NF FAR/F
FAR/
F FAR/F
12 NF NF NF NF FAR NF NF FAR FAR FAR/NF
UT6a
1 F FAR FAR FAR FAR FAR FAR FAR FAR FAR
2 F FAR FAR FAR FAR FAR FAR FAR FAR FAR
3 FAR FAR FAR FAR FAR NF FAR FAR FAR FAR
4 NF FAR FAR FAR FAR FAR FAR FAR FAR FAR
5 FAR FAR FAR FAR FAR FAR FAR F FAR FAR
6 FAR FAR FAR FAR FAR FAR FAR FAR FAR FAR
7 FAR FAR FAR FAR FAR NF FAR FAR FAR FAR
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UT6a1 1 FAR FAR F FAR FAR FAR FAR F F FAR
UT6a2 1 FAR FAR F FAR FAR F FAR F FAR FAR
2 F FAR FAR F FAR FAR FAR F F F
UT6b
1 F F F F F FAR FAR FAR F F
2 F F FAR F FAR FAR F FAR NF F
3 FAR FAR FAR FAR FAR FAR FAR F
FAR/
F FAR
4 NF FAR NF NF NF FAR NF FAR F NF
UT6c
1 F F F F F FAR F F N/A F
2 NF NF NF NF NF NF NF FAR N/A NF
3 F F F F F NF FAR F N/A F
4 WETLAND COMPLEX
UT6e
1 NF NF FAR NF NF FAR FAR/NF FAR FAR NF
2 FAR NF FAR FAR FAR FAR FAR FAR FAR FAR/NF
3 F F F F F FAR F F F F
4 FAR FAR FAR FAR FAR FAR FAR F FAR FAR/NF
5 FAR FAR FAR F F NF FAR F FAR FAR
UT6e1
1 F F F F F NF F F NF F
2 FAR FAR FAR FAR FAR FAR FAR FAR FAR FAR
3 F F F F FAR FAR FAR FAR NF FAR
4 FAR FAR FAR F F NF FAR FAR FAR FAR
UT6e1
a 1 FAR FAR FAR F F NF FAR FAR FAR FAR
UT6f 1 FAR FAR FAR FAR FAR FAR FAR F FAR FAR
UT6g 1 F F FAR F F F F F F F
UT8
1 F F F F F F F F F F
2 F F FAR F F F F F F FAR/F
3 F F F F F FAR F F NF FAR/F
4 WETLAND COMPLEX
5 WETLAND COMPLEX
6
REACH EXTREMELY SHORT THEREFORE INDIVIDUAL PARAMETERS NOT
ASSESSED F
UT8a 1 F F F F F F F F FAR F
UT9 1 F F F F F F F F F F
2 NF NF NF FAR FAR F NF F NF NF
Table 1: Piney Run Function Based-Assessment Ratings which include functioning (F), functioning-at-risk (FAR), and not-functioning (NF). FAR/F indicates transition from functioning-at-risk to functioning
and FAR/NF indicates transition from functioning-at-risk to not functioning.
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B. CHANNEL EVOLUTION
Channel evolution can be used to characterize natural trends that will determine the future
stability of stream channels. Stable reaches are characterized as functioning in channel evolution
and have evolved to channel dimensions and plan form that maintain equilibrium conditions in
the new environment. This includes vertical and lateral stability from channels having formed a
new floodplain with meanders where possible. Overall, approximately one-third of the Piney
Run project area reaches (23 assessment reaches) have reached an evolutionary end-point and
will be stable with the new environmental conditions.
Assessment reaches that are characterized as functioning-at-risk for channel evolution are in the
mid-point of their evolutionary transition to adjust to new environmental conditions.
Approximately two-thirds of the Piney Run project (43 of the 74 assessment reaches) have
undergone vertical adjustments and channel degradation with the floodplain being fully
developed. These are an indicator of adjustments required for future channel stability in the new
environmental conditions. Further stability will then occur from bank stabilization that may take
decades or longer to fully establish. Development of riparian vegetation will help promote
stability of channel banks, plan, and profile. However, it will take a considerable time for these
reaches to adjust their plan form to reach stable conditions necessary to equilibrate with changes
to stream energy and sediment supply.
Finally, approximately one-tenth (8 assessment reaches) of the Piney Run reaches are
characterized for channel evolution as reaches that are not functioning or are transitioning from
functioning-at-risk to not functioning. This characterization describes reaches that are just
beginning downcutting and are undergoing significant lateral erosion in an attempt to adjust to
the new environmental conditions. The streams are beginning the evolution transition and will
take a considerable time to adjust their grade and plan form to reach the stable conditions
necessary to equilibrate with changes to stream energy and sediment supply.
C. LEVEL 3 DETAILED ASSESSMENT REACHES
Representative reaches (Figure 5) were identified within Phase 1 of the Piney Run restoration
area as reaches that could be used to develop existing geomorphic conditions and verify design
ratios for the majority of the restoration site. These reaches were selected by valley type, stream
type, function-based condition and restoration potential. The distribution of reaches that were
represented is shown below in Table 2.
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Level 3 Detailed Assessment Reach Distribution
Detailed
Assessment
Reach
Represented Reach
Piney Run Piney Run Reaches 1 - 7
UT6 Upper UT6 Reaches 1 - 6, UT6e Reaches 1 - 5, UT6e1 Reaches 1 - 4
UT6 Middle UT6 Reaches 7 - 9
UT6 Lower UT6 Reaches 10 - 12
UT6a Lower UT6a Reaches 1 - 7, UT6a1 Reach 1, UT6a2 Reaches 1 - 2
Table 2: Piney Run Level 3 Detailed Assessment Reach Distribution
In addition to the Rapid Stream-Function Based Assessment (Davis, et al., 2014) and Bank
Erosion Hazard Index / Near-Bank Stress survey (Rosgen, D.L., 2009) conducted throughout the
project area, detailed geomorphic assessments were conducted in these “representative” locations
in accordance with Rosgen Level III procedures. Collecting detailed information from these
representative reaches allowed the design team to characterize existing conditions quantitatively
and gather data necessary for design development. The summary information for each of these
sites can be found below with detailed information available in Appendix C.
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Figure 5: Representative Reaches with Level 3 Detailed Assessment
1. Representative Reach - Piney Run
The Service determined that the overall function-based condition of the main stem of Piney Run
is Functioning at Risk and is trending towards stability. It is perennial and classified as an
unstable Rosgen C4. The stream is slightly incised but not entrenched and therefore is somewhat
connected to its floodplain during larger than bankfull flood events. The floodplain is very broad
in relation to stream channel width with some concentrated flow paths from steep terrain nearby,
but is mostly sheet flow. Stream bank erosion is localized, mainly associated with outside
meander bends, and the channel exhibits indices of high levels of bank erosion and near bank
shear stress. The materials eroding from the stream banks are contributing to the sediment load
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being delivered to the project areas downstream. The pools and riffles are well defined and the
pools depths are sufficiently able to promote good shelter for fish and macroinvertebrates. The
riparian vegetation is poor, and consists primarily of mixed pasture grasses and very few trees or
shrubs. Rooting depth of vegetation is shallow, which exacerbates bank erosion. The water
quality of the project area is fair and impaired mostly by temperature and stormwater runoff from
higher in the watershed. The water throughout the reach is clear and only cloudy after rain
events. Minimal woody debris or detritus was present throughout this reach.
Based on the Services Rapid Stream Function – Based Assessment, the Biology is fair since
there is presence of tolerant fish and macroinvertbrates. Table 3 shows the parameters collected
and function-based ratings given for this reach. More detailed biologic data from Piney Run can
also be found below, in Section VI.C.6-Biology.
Table 3: Piney Run Main Function-based Assessment Table
Piney Run Main is undergoing channel evolution from a Rosgen C4 stream type towards a
stable, functioning C4 stream. The stream is slightly incised likely due to previous degradation;
however it is no longer adjusting vertically. There are some areas of active lateral erosion that
Value Rating Overall by Level Overall Reach
Bank Height
Ratio1.2 FAR
Entrenchment
Ratio8.84 FAR
Floodplain DrainageFWS Rapid
Assessment Visual FAR
Riparain VegetationFWS Rapid
Assessment Visual FAR
Dominant Bank
Erosion RateH/H FAR
Meander Width
Ratio1.3 - 3.3 FAR
Shelter for Fish Visual FAR
Pool-to-pool
Spacing1.0 - 3.4 FAR
Pool Depth
Variability2.2 - 2.5 F
Water Appearance
and Nutrients
FWS Rapid
Assessment Visual FAR
DetritusFWS Rapid
Assessment Visual FAR
Macro Species and
RichnessBIBI Poor NF
Fish Species and
RichnessFIBI Good F
FAR
2 - Hydraulics
Piney Run Main
Level and
CategoryParameter
Measurement
Method
Pre-Restoration Condition
Floodplain
ConnectivityFAR
3 -
GeomorphologyFAR
Lateral Stability
Bedform Diversity
4 -
PhysicochemicalFAR
5 - Biology FAR
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will continue to occur until addressed. Because of these instabilities, the channel evolution rating
of the reach was considered to be functioning-at-risk, as shown in Table 4. It is important to
note however, that the current stable configuration is much smaller than it was historically. Since
the construction of the Piney Run reservoir upstream, the amount of unrestricted drainage to this
point has been reduced, allowing for a smaller channel configuration to exist. This is evidenced
by the fact that this smaller channel is beginning to form within the bounds of the larger channel
that once existed. Depositional features are present indicating the generation of a new floodplain
within the bounds of the old channel.
Table 4: Piney Run Main Channel Evolution Rating
2. Representative Reach - UT6 Upper
The Service determined that the overall function-based condition of UT6 Upper is Functioning
at Risk and is trending towards stability. It is perennial and classified as an unstable Rosgen B4c.
The stream is slightly incised but not entrenched and therefore, is connected to its floodplain
during bankfull and larger flood events. The floodplain is relatively narrow in relation to stream
channel width, with some concentrated flow paths from steep terrain nearby. Stream bank
erosion is localized and the channel exhibits indices of moderate bank erosion and near bank
shear stress. While minor, the materials eroding from the stream banks are contributing to the
sediment load being delivered to the project areas downstream. The pools and riffles are well
defined and the pools depths are sufficiently able to promote good shelter for fish and
macroinvertebrates. The riparian vegetation is moderate to good, and consists primarily of
mixed hardwood canopy trees with a thin understory. The water quality of the project area is fair
and impaired mostly by temperature and stormwater runoff for higher in the watershed. The
water throughout the reach is clear, and an abundance of detritus is present.
Based on the Services Rapid Stream Function – Based Assessment, the Biology is fair since
there is presence of tolerant macroinvertbrates. No fish were seen or identified in this particular
reach. Table 5 shows the parameters collected and function-based ratings given for this reach.
Piney Run Main - Function-based Assessment Summary and Channel Evolution
Reach Length (ft)
Rosgen
Stream
Type
Channel Evolution Reach Level Function-
based Rating
908 C4 Unstable C4 C4 FAR
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Table 5: UT6 Upper Function-based Assessment Table
UT6 Upper is undergoing channel evolution from an unstable Rosgen B4c stream type towards a
stable B4c. The stream is slightly incised likely due to previous degradation, however it is no
longer adjusting vertically. This is evidenced by the exposed bedrock throughout the stream
reach that provides vertical grade control. There are some areas of active lateral erosion that will
continue to occur until addressed. Because of these instabilities, the channel evolution rating of
the reach was considered to be functioning-at-risk, as shown in Table 6.
Table 6: UT6 Upper Channel Evolution Rating
Value Rating Overall by Level Overall Reach
Bank Height
Ratio1.37 FAR
Entrenchment
Ratio1.82 FAR
Floodplain DrainageFWS Rapid
Assessment Visual FAR
Riparain VegetationFWS Rapid
Assessment Visual FAR
Dominant Bank
Ersoion RateM/M FAR
Meander Width
Ration/a n/a
Shelter for Fish Visual F
Pool-to-pool
Spacing2.1 - 7.0 F
Pool Depth
Variability1.7 - 2.0 F
Water Appearance
and Nutrients
FWS Rapid
Assessment Visual F
DetritusFWS Rapid
Assessment Visual F
Presence Present F
Tolerance Moderate FAR
Fish Presence Absent NF
Lateral Stability
Bedform Diversity
4 -
PhysicochemicalF
UT6 Upper
Level and
CategoryParameter
Measurement
Method
Pre-Restoration Condition
5 - BiologyMacro
FAR
FAR
2 - Hydraulics
Floodplain
ConnectivityFAR
3 -
GeomorphologyF
UT6 Upper - Function-based Assessment Summary and Channel Evolution
Reach Length (ft)
Rosgen
Stream
Type
Channel Evolution Reach Level Function-
based Rating
402 B4c Unstable B4c B4c FAR
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3. Representative Reach - UT6 Middle
The Service determined that the overall function-based condition of UT6 Middle is Functioning
at Risk and is trending towards further instability. It is perennial and classified as an unstable
Rosgen C4. The stream is moderately incised but not entrenched and therefore, is only
connected to its floodplain during greater than bankfull flood events. The floodplain is broad in
relation to stream channel width, with some concentrated flow paths from wetlands and
floodplain depressions nearby. Stream bank erosion is widespread and the channel exhibits
indices of high to very high bank erosion and near bank shear stress. The materials eroding from
the stream banks are contributing to the sediment load being delivered to the project areas
downstream. The pools and riffles are not well defined and the pools depths are less than
desirable for fish and macroinvertebrate habitat. The riparian vegetation is lacking, and consists
primarily of mixed pasture grasses with very few shrubs and/or trees for shading or soil stability.
The water quality of the project area is fair and impaired mostly by temperature and stormwater
runoff from higher in the watershed. The water throughout the reach is clear to cloudy, however
no detritus is present.
Based on the Services Rapid Stream Function – Based Assessment, the Biology is functioning-
at-risk since there is presence of tolerant fish and macroinvertbrates. Table 7 shows the
parameters collected and function-based ratings given for this reach.
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Table 7: UT6 Middle Function-based Assessment Table
UT6 Middle is undergoing channel evolution from a Rosgen unstable C4 stream type towards an
intermediate F4 stream type, and ultimately a B4c channel. It is undergoing major changes and is
not stable in its current configuration. The ability of the stream to evolve back to some level of
quasi-equilibrium is unlikely to occur anytime in the near future without intervention. The
geomorphic functions are still undergoing significant adjustment. The stream still seems to be
adjusting vertically; however, lateral erosion is more prevalent throughout the reach and will
continue to occur until it is reconnected to a new stable floodplain. During this time, riparian
vegetation needs to establish and mature in order to assist in slowing down lateral erosion rates.
Given the current stability condition, the recovery of the stream within the project area could
take several years or even possibly decades to occur, and during this time could adversely affect
downstream resources. Because of these instabilities, the channel evolution rating of the reach
was considered to be functioning-at-risk but is quickly trending towards non-functioning, as
shown in Table 8.
Value Rating Overall by Level Overall Reach
Bank Height
Ratio1.51 FAR
Entrenchment
Ratio3.65 F
Floodplain DrainageFWS Rapid
Assessment Visual FAR
Riparain VegetationFWS Rapid
Assessment Visual FAR
Dominant Bank
Ersoion RateH/H NF
Meander Width
Ratio1.8 - 6.8 FAR
Shelter for Fish Visual FAR
Pool-to-pool
Spacing18 - 128 FAR
Pool Depth
Variability2.1 - 2.8 FAR
Water Appearance
and Nutrients
FWS Rapid
Assessment Visual FAR
DetritusFWS Rapid
Assessment Visual NF
Presence Moderate FAR
Tolerance Moderate FAR
Fish Presence Absent NF
FAR
2 - Hydraulics
UT6 Middle
Level and
CategoryParameter
Measurement
Method
Pre-Restoration Condition
Floodplain
ConnectivityFAR
3 -
GeomorphologyFAR
Lateral Stability
Bedform Diversity
4 -
PhysicochemicalFAR
5 - BiologyMacro
FAR
Piney Run Stream Restoration: Project Summary and Design Report
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Table 8: UT6 Middle Channel Evolution Rating
4. Representative Reach - UT6 Lower
The Service determined that the overall function-based condition of UT6 Lower is Functioning
at Risk and is trending towards further instability. It is perennial and classified as an unstable
Rosgen E4. The stream is slightly incised but not entrenched and therefore, is connected to its
floodplain at larger than bankfull flood events. The floodplain is broad in relation to stream
channel width, with some concentrated flow paths from wetland seeps and sheet flow
concentrations nearby. Stream bank erosion is widespread and the channel exhibits very high to
extreme indices of bank erosion and near bank shear stress. The materials eroding from the
stream banks are contributing to the sediment load being delivered to the project areas
downstream. The pools and riffles are poor to moderately defined, while the pools depths are
moderate and promote some shelter for fish and macroinvertebrates. The riparian vegetation is
poor and consists primarily of mixed grasses and very few canopy trees or shrubs. The water
quality of the project area is fair and impaired mostly by temperature and stormwater runoff
higher in the watershed. The water throughout the reach is clear to cloudy, and limited detritus is
present.
Based on the Services Rapid Stream Function – Based Assessment, the Biology is fair since
there is presence of tolerant macroinvertbrates. Fish were seen in many of the pools throughout
this reach. Table 9 shows the parameters collected and function-based ratings given for this
reach.
UT6 Middle - Function-based Assessment Summary and Channel Evolution
Reach Length (ft)
Rosgen
Stream
Type
Channel Evolution Reach Level Function-
based Rating
352 C4 Unstable C4 F4B4c FAR
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Table 9: UT6 Lower Function-based Assessment Table
UT6 Lower is undergoing channel evolution from an unstable Rosgen E4 stream type, towards
an unstable C4 stream type. It is undergoing some major adjustment. The stream is slightly
incised, likely due to previous land use changes and poor agricultural techniques. The channel
has reached an equilibrium in vertical adjustment, as it has matched the elevation of Piney
mainstem. Additionally, the stream cannot headcut upstream any further due to the box culvert
on Slacks Road. There is however, widespread active lateral erosion that will continue to occur
until addressed. Because of these instabilities, the channel evolution rating of the reach was
considered to be functioning-at-risk and trending towards not-functioning, as shown in Table
10.
Value Rating Overall by Level Overall Reach
Bank Height
Ratio1.23 FAR
Entrenchment
Ratio20.16 F
Floodplain DrainageFWS Rapid
Assessment Visual FAR
Riparain VegetationFWS Rapid
Assessment Visual FAR
Dominant Bank
Ersoion RateVH/VH NF
Meander Width
Ratio0.5 - 3.5 NF
Shelter for Fish Visual FAR
Pool-to-pool
Spacing1.0 - 3.5 FAR
Pool Depth
Variability2.0 - 2.6 FAR
Water Appearance
and Nutrients
FWS Rapid
Assessment Visual FAR
DetritusFWS Rapid
Assessment Visual FAR
Presence Rare FAR
Tolerance Moderate FAR
Fish Presence Rare FAR
FAR
2 - Hydraulics
UT6 Lower
Level and
CategoryParameter
Measurement
Method
Pre-Restoration Condition
Floodplain
ConnectivityFAR
3 -
GeomorphologyFAR
Lateral Stability
Bedform Diversity
4 -
PhysicochemicalFAR
5 - BiologyMacro
FAR
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Table 10: UT6 Lower Channel Evolution Rating
5. Representative Reach - UT6a Lower
The Service determined that the overall function-based condition of UT6a Lower is Functioning
at Risk and is trending towards stability. It is perennial and classified as an unstable Rosgen B4c.
The stream is moderately incised and moderately entrenched and therefore, is not connected to
its floodplain during bankfull and may only reach the floodplain area during larger flood events.
The floodplain is broad in relation to stream channel width, with some concentrated flow paths
from steeper terrain nearby. Stream bank erosion is widespread throughout the reach, which
exhibits indices of high to very high bank erosion and near bank shear stress. The materials
eroding from the stream banks are contributing to the sediment load being delivered to the
project areas downstream. The pools and riffles are moderately defined, however riffles are
short and pools are closely spaced. The pools depths have good variability and promote good
shelter for fish and macroinvertebrates. The riparian vegetation is fair, and consists primarily of
grasses, some shrubs and very few canopy trees. The water quality of the project area is fair and
impaired mostly by temperature and stormwater runoff for higher in the watershed. The water
throughout the reach is clear, and very little detritus is present.
Based on the Services Rapid Stream Function – Based Assessment, the Biology is fair since
there is presence of fish and tolerant macroinvertbrates. Table 11 shows the parameters collected
and function-based ratings given for this reach.
UT6 Lower - Function-based Assessment Summary and Channel Evolution
Reach Length (ft)
Rosgen
Stream
Type
Channel Evolution Reach Level Function-
based Rating
554 E4 Unstable E4 Unstable C4 FAR
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Table 11: UT6a Lower Function-based Assessment Table
UT6a Lower is undergoing channel evolution from a Rosgen B4c stream type towards a stable
B4c. It is undergoing some major adjustment. The stream is slightly incised likely due to
previous land use changes and poor agricultural techniques. The channel has reached an
equilibrium in vertical adjustment as it has matched the elevation of UT6 downstream. There is
however, widespread active lateral erosion that will continue to occur until addressed. Because
of these instabilities, the channel evolution rating of the reach was considered to be functioning-
at-risk and trending towards not-functioning, as shown in Table 12.
Table 12: UT6a Lower Channel Evolution Rating
Value Rating Overall by Level Overall Reach
Bank Height
Ratio2 NF
Entrenchment
Ratio1.61 NF
Floodplain DrainageFWS Rapid
Assessment Visual FAR
Riparain VegetationFWS Rapid
Assessment Visual NF
Dominant Bank
Ersoion RateH/VH FAR
Meander Width
Ratio0.6 - 4.3 FAR
Shelter for Fish Visual FAR
Pool-to-pool
Spacing3.0 - 4.0 FAR
Pool Depth
Variability>1.5 F
Water Appearance
and Nutrients
FWS Rapid
Assessment Visual FAR
DetritusFWS Rapid
Assessment Visual FAR
Presence Rare FAR
Tolerance Moderate FAR
Fish Presence Rare FAR
FAR
2 - Hydraulics
UT6a Lower
Level and
CategoryParameter
Measurement
Method
Pre-Restoration Condition
Floodplain
ConnectivityNF
3 -
GeomorphologyFAR
Lateral Stability
Bedform Diversity
4 -
PhysicochemicalFAR
5 - BiologyMacro
FAR
UT6a Lower - Function-based Assessment Summary and Channel Evolution
Reach Length (ft)
Rosgen
Stream
Type
Channel Evolution Reach Level Function-
based Rating
348 B4c Unstable B4c B4c FAR
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6. Biology
The Service only conducted visual monitoring on the Piney Run reaches for Level-5 biology
survey. While telling, this is merely an estimation method to generate inferences about the
condition of the system. In order to understand the biology of the system more comprehensively,
the MDNR MBSS team developed a monitoring plan to capture the baseline biologic condition
of the Piney Run project area. The MBSS team selected nine sites to track progress of the
restoration effort. Six sites were located on Piney Run and included three sites chosen to serve as
control sites for the restoration and three sites located on the portion that is to be restored (Figure
6). However, since the restoration effort has been split into a phased approach, the only MBSS
monitoring site within the current restoration area, and the area this report primarily focuses on,
is site 303 shown in Figure 6.
Figure 6: Piney Run MBSS Sampling Site Locations
The MBSS protocol focuses on key factors influencing biologic condition. Those factors include
temperature, benthic macroinvertebrates, fish, physical habitat, water chemistry, and
geomorphology. All data were collected using standard MBSS protocols. A detailed description
of these protocols is available in Stranko et al., 2007.
While geomorphic conditions can be a good representation of stream stability, water quality must
be intact to support biology. Water quality measurements taken include both continuous water
temperature and chemistry. The findings of the MBSS analysis showed that the water
temperature generally stayed below the threshold for tolerant cold water fish, such as brown
trout, but did not meet the standards to be considered a Maryland Use Class III stream. Similarly,
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water chemistry was found to support tolerant cold water fish but conductivity and sulfate
concentrations could limit potential for abundant populations of trout.
Benthic macroinvetebrates index of biotic integrity, or “BIBI” was measured at each of the six
sites on Piney Run during the spring index period in 2014. The data collected assess the
macroinvertebrate species and richness in a given area. The sites surveyed on the Piney Run
project area ranged between 1.67 and 2.67 which plots low or “poor” as compared to the
reference sites. This means that currently, this portion of Piney Run does not provide the habitat
necessary to support these species. The most notable deficiency included the lack of detritus,
shading, and pool depth to provide shelter for these species. Additional data can be found in
Appendix D.
Fish indices of biotic integrity, or “FIBI” data, was also collected at each of the six sample sites
on Piney Run. Both the restoration sites and control sites scored well and were considered
“good” based on the criteria set forth by the MBSS protocol. The IBI values are shown below in
Table 13 and additional data can be seen in Appendix D.
Site
Control Restoration Reference
206 205 302 204 201 303 Jones Falls Timber Run Brice Run
Year 2014 2014 2014 2014 2013 2014 2014 2013 2014 2001 2013 2014 2013 2014
BIBI 2.33 2.33 1.67 2.67 2.00 2.67 2.67 3.00 3.00 5.00 4.67 4.00 3.67 3.00
FIBI 4.00 4.00 4.00 4.00 4.67 4.67 4.67 3.33 3.67 4.67 4.67 4.33 4.67 5.00
Table 13: Piney Run Indices of Biotic Integrity
VII. WETLAND ASSESSMENT
The Service and MDNR performed a wetland assessment throughout the Phase 1 project area to
verify the location of the National Wetlands Inventory (NWI) wetlands, and to identify other
existing wetland locations. This assessment was done in support of the project goal to increase
water quality through wetland enhancement and creation. Maximizing the amount of floodplain
complexity and wetland habitat are crucial factors that have benefits for water quality and
various Federal Trust species. Reconnecting a stream to its floodplain is one strategy that can
help reduce the amount of nitrogen found in stream systems. Stream restoration projects that
increase floodplain connectivity have been found to have higher denitrification rates than streams
that were restored with higher banks (Kaushal et al., 2008). Seasonal isolated wetlands, such as
vernal pools, provide excellent breeding habitat for species such as Spotted Salamander, Gray
Tree Frog and Northern Green Frog (Mitchell et al., 2006). Emergent wetlands provide food,
shelter, resting places, and nurseries for a variety of species, including migratory birds,
waterfowl, and other wildlife (Hayes, 1996.)
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Figure 7: Piney Run wetland locations identified by MDNR
In general, the assessment found that the wetlands in the Phase 1 area matched up fairly well
with the NWI locations, with a few additional existing wetland locations identified. All of the
wetlands are considered to be emergent. Emergent wetlands are classified by the presence of
rooted herbaceous hydrophyte vegetation that is present over most of the growing season
(Cowardin et al., 1979). Figure 7 above shows the location of wetlands across the project area.
Opportunities for wetland creation include construction of vernal pools and oxbows, as well as
emergent wetlands with hummocks. Existing wetlands can be enhanced through removal of
invasive species and planting of obligate and facultative wetland plants. Further details on the
wetland assessment and recommendations can be found in Appendix E.
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VIII. DESIGN DEVELOPMENT
This section presents the project constraints, restoration potential, design objectives, design
alternatives analysis, and project descriptions involved in the Piney Run Stream Restoration.
A. PROJECT AREA DELINEATION
The Service identified 16 distinct project areas (Figure 8) based primarily on the proposed
project reach design approach. The design approaches were selected through a design
alternatives analysis based on project goals, design objectives, existing conditions, constraints,
restoration potential, proposed uplift, impacts to existing resources, uncertainty, risk, and
implementation costs.
Figure 8: Project Reach Delineation
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B. CONSTRAINTS
Constraints are man-made features that have the ability to influence stream restoration potential.
The Service identified a variety of constraints that will influence the final design solution for the
proposed project area. In some instances, the constraints are relatively minor and in other
instances they are major (Figure 9). In either instance, these constraints were addressed
throughout the design phase and were actively considered when developing design goals and
objectives.
Figure 9: Project Constraints
The largest project constraint is Piney Reservoir. It is located approximately 2 miles upstream of
Project Areas 7 and 8 and significantly affects the flow regime for these project areas. A
discharge analysis (Section VIII.F.4-Hydrologic and Hydraulic Analyses) determined that the
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hydrograph influencing Project Areas 7 and 8 is primarily influenced by the drainage area
downstream of the reservoir versus the entire watershed drainage area. This is because
maximum flow releases from Piney Reservoir do not exceed flows greater than a 1 year storm
event. Therefore, Project Areas 7 and 8 have flow discharges and channel dimension
characteristics associated with the drainage area downstream of the reservoir, which is 4.6 square
miles versus the 15.2 square miles associated with the entire watershed. This constraint will
significantly influence design channel dimensions, specifically a smaller channel then what
would be expected for a project drainage area of 15.2 square miles.
The next largest constraint is the sanitary sewer that is parallel to Project Areas 1 through 8. The
sanitary sewer has the potential to influence the width of constructed floodplains within these
reaches. However, only the floodplain widths in Project Areas 5 and 7 are constrained by the
sanitary sewer. The floodplain width design objectives can be achieved in all of the other project
areas.
Roadway crossings are constraints in two locations within the project area. They constrict flood
flows and influence streambed and floodplain elevations. Flood flows are constricted in Project
Areas 5 and 6 because the bridge culverts are undersized and can cause back water effects
upstream of the road crossing and elevated stream shear stresses downstream. The streambed and
floodplain elevations cannot be raised in Project Areas 5, 6 and 7 because raising these
elevations can elevate flood levels and increase the potential for the roadway crossings to be
overtopped by flood flows.
The last constraint is a horse farm within Project Area 5. The horse farm pastures are near the
stream channel and limit design floodplain widths.
C. RESTORATION POTENTIAL
Restoration potential is the highest level of restoration or functional uplift that can be achieved
given the watershed health, reach-level function-based condition, stressors and constraints
(Harman et al., 2012). Based on these factors, the Service determined that all Project Areas can
achieve fully functioning Pyramid Levels 2 - Hydraulics and 3 - Geomorphology and partial
uplift for Pyramid Levels 1 – Hydrology, 4 – Physicochemical and 5 – Biology.
Potential for partial uplift of Pyramid Level 1 – Hydrology will come from eliminating
concentrated flows and increasing floodplain areas for flow attenuation. Project Areas 1, 2, 4, 5,
6, 9, 11, 13 and 15 have the highest potential for hydrological uplift because these reaches have
the largest existing sources of concentrated flow. Project Area 8, the farthest downstream project
area, has the greatest potential for an altered flow regime, specifically reduced peak flow floods.
This is possible through the proposed creation of large wetland areas in Project Areas 6 and 7.
However, the modeling required to determine this is not part of this study and therefore, cannot
be verified.
Restoration of Levels 2 and 3 functions are typically the easiest to achieve since they involve
direct, physical manipulation of stream channel dimension, pattern, and profile. Stream channel
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parameters such as belt width, bank heights, floodplain width, facet feature lengths, slopes and
depths can be constructed to specifications considered functioning.
Potential for partial uplift of Pyramid Level 4 – Physicochemical is mainly influenced by
watershed health, but can be improved through reach level restoration activities. Stream bank
stabilization can significantly reduce sediment and nutrient inputs. Additionally, the creation of
floodplain wetlands can reduce sediment and nutrient loads. Wetland areas are proposed in
Project Areas 2 - 7 and 15. The effectiveness of floodplain wetlands will be greater in Project
Areas 3, 6 and 7 due to the larger extent of proposed wetland areas. Lastly, the establishment of
riparian vegetation can shade the stream and help reduce stream temperature.
Potential for partial uplift for Pyramid Level 5 – Biology will come from improved water quality
and in-stream habitat. Project Areas 2 – 7, 9, 12, and 15 have the highest potential for biological
uplift because these reaches have the poorest current in-stream habitat conditions.
D. DESIGN OBJECTIVES
Design objectives are based on project goals and project area restoration potential. The
objectives reflect the project goals but state specifically how the project will be completed. Thus,
design objectives are quantifiable and measurable. The goals of the study are to improve water
quality through sediment and nutrient reduction, create native riparian habitat for Yellow
Warbler, Eastern Wood-Peewee, Red-Shoulder Hawk and Acadian Flycatcher, and improve and
preserve downstream habitat for American Eel and other aquatic species through stream
restoration.
The Service developed, in coordination with MDNR, design objectives to address the design
goals. Varying existing stream conditions within the project require restoration efforts ranging
from relatively minor localized restoration activities to major, system-wide restoration activities.
Project Areas 1, 2, 8, 10 - 13 and 16 have localized instability conditions and will only require
minor restoration activities to meet the design goals. Project Areas 3 -7, 9, 14 and 15 have
system-wide instability conditions and will require significant restoration activities to meet the
design goals. Therefore, two sets of design objectives were developed (Table 14 and Table 15)
Piney Run Project Areas 1, 2, 8, 10 - 13 and 16 - Design Objectives
Level and
Category Parameters Design Objectives
Level 3 -
Geomorphology
1. Lateral
Stability
2. Sediment/Re
duction and
Trapping
3. Bedform
Diversity
4. Riparian
Buffer
1. Reduce stream bank erosion rates to match reference
erosion rates (bank migration/lateral stability).
2. Decrease sediment loads leaving the project to loads less
than entering loads entering the project.
3. Increase pool to riffle ratio to 60/40.
4. Create native riparian buffer for Yellow Warbler, Eastern
Wood-Peewee, Red-Shoulder Hawk, and Acadian
Flycatcher.
Table 14: Piney Run Project Areas 1, 2, 8, 10 - 13 and 16 - Design Objectives
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Table 15: Piney Run Project Areas 3 -7, 9, 14 and 15 - Design Objectives
E. DESIGN ALTERNATIVES ANALYSIS
The purpose of the design alternatives analysis is to select the best restoration design solution
that meets the project goals and design objectives based on watershed and reach conditions,
restoration potential, and constraints. It focuses on how a specific design solution and restoration
activities could influence existing stream functions (both potential uplift and loss),
implementation costs, uncertainty and risk.
As stated above in the design objectives section, the project essentially has two broad restoration
needs: localized, minor restoration activities and system-wide, major restoration activities. A
design alternatives analysis was not conducted for Project Areas 1, 2, 8, 10 - 13 and 16 since the
Piney Run Project Areas 3 -7, 9, 14 and 15 - Design Objectives
Level and
Category Parameters Design Objectives
Level 1-
Hydrology
1. Concentrated
Flows
1. Eliminate concentrated flows.
Level 2 -
Hydraulics
2. Floodplain
Connectivity
3. Floodplain
Complexity
2. Set floodplain elevations to historic floodplain
elevations, where it exists. Create floodplain connection
to allow for inundation by flood flows less than bankfull
flows. Maximize valley width to create floodplain.
3. Increase floodplain complexity by eliminating
concentrated flows, creating wetlands and providing
areas to trap and store flood flows.
Level 3 -
Geomorphology
5. Lateral
Stability
6. Sediment
Reduction
7. Sediment
Transport
8. Bedform
Diversity
9. Riparian
Buffer
5. Reduce stream bank erosion rates to match reference
erosion rates (bank migration/lateral stability).
6. Decrease sediment loads leaving the project area to loads
less than entering the project area.
7. Transport the sediment supply being delivered to the
project area without excessive degradation or
aggradation.
8. Increase pool to riffle ratio to 60/40
9. Create native riparian buffer for Eastern Wood-Peewee,
Red-Shoulder Hawk, and Acadian Flycatcher and make
buffer width 150 ft wider than required meander width
ratio.
Level 4 -
Physicochemical
10. Nutrient
Levels 10. Reduce nutrient levels compared to existing conditions.
Level 5 -
Biology
11. Macros
12. Fish
11. Increase macro diversity and density conditions
compared to existing conditions
12. Increase fish diversity and density conditions compared
to existing conditions
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restoration activities will be localized and minor. Additionally, potential adverse impacts to
existing resources will be avoided and/or minimized. However, a brief description of proposed
uplift and potential adverse impacts for each of these project areas is described below in Section
VIII.F.2-Proposed Project Area Descriptions.
For Project Areas 3 -7, 9, 14 and 15, the Service conducted a design alternatives analysis where
technically and economically feasible restoration solutions were developed and the overall
process was described to allow for meaningful and informed decision making.
1. Potential Design Alternatives
There are a variety of design restoration solutions available to achieve the primary design goal of
nutrient and sediment load reduction. Many of these approaches focus on increasing the
frequency, magnitude, and duration of flood flows to the floodplain. Essentially, as flood flows
interact with ground surfaces more frequently and for longer durations, there is a greater
potential for nutrient and sediment load reduction. However, stream energy and sediment supply
are two significant factors that influence floodplain inundation and the range of feasible design
solutions.
Streams with low energy and low sediment supply allow for the greatest variety of design
solutions because they are considered low risk. They are considered low risk because low
energy streams have less potential for excessive stream erosion, and limited sediment supply
streams, along with low energy, have less potential for excessive sediment deposition. One of the
most effective design approaches for streams with low stream energy and a limited sediment
supply involves designing a base flow channel. A base flow channel is designed so that
relatively frequent storm events can easily access and inundate the floodplain. To do this, base
flow channels typically have channel dimensions (area, width and depth) less than what would
be shown in a Hydrologic Regional Bankfull Discharge and Channel Characteristics Curve. This
design approach is commonly referred to as valley restoration and/or legacy sediment design.
Streams with moderate to high stream energy and sediment supply can be considered higher risk
projects and therefore, have a lower variety of design solutions. Moderate to high energy
streams have high shear stresses and the potential for excessive lateral and vertical erosion.
Moderate to high sediment supply streams have the potential to produce excessive sediment
deposition or excessive erosion depending on the stream energy. Excessive sediment deposition
occurs when the rate of deposition exceeds the ability for vegetation to establish, which in turn
accelerates bank and bed erosion. This means that the stream channel and floodplain are in a
constant state of flux, adversely affecting water quality and biology. If the sediment deposition
occurs at a rate that allows vegetation to establish, then bank and bed stability can be achieved.
Over time the sediment deposition will most likely form a stream channel that can transport the
sediment supply being delivered to the project area. Design approaches appropriate for these
stream conditions are commonly referred to as Natural Channel Design, and involve designing a
channel shaped to transport the sediment supply at bankfull flow (the channel forming discharge
flow). The channel dimensions associated with this design would correlate well with a
Hydrologic Regional Bankfull Discharge and Channel Characteristics Curve. It should be noted
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though, that a base flow channel design could be used on these stream conditions if the sediment
deposition rate does not have adverse aggradation impacts.
2. Design Alternatives Analysis
The Service focused on developing potential restoration design alternatives that would result in
frequent overbank flows and floodplain inundation. They first evaluated the alternatives based
on how proposed channel and floodplain characteristics influenced sediment transport and
stream energy. This involved identifying sediments sources and load amounts and calculating
stream energy based on watershed size and valley slope. Each alternative was then evaluated
based on their ability to achieve the design goals and objectives and minimize potential adverse
impacts to existing resources.
a. Sediment Supply
There are two sources of sediment supply being delivered to the project area. One is from
eroding stream banks within the project area and the other is from sources upstream of the
project area. The sediment load being supplied from eroding stream banks within the project
area will be significantly reduced through restoration activities associated with the overall
proposed stream design.
To determine the sediment loads being supplied from upstream watersheds, the Service
conducted a rapid watershed assessment of the four watersheds upstream of the project area
(Figure 3: Piney Run Watershed and Subwatershed Delineation). Project Area 7 is influenced by
the Piney Run Watershed; Project Areas 3 – 6 are influenced by UT6 Watershed; Project Area 9
is influenced by UT6e Watershed and Project Area 15 is influenced by UT6a Watershed. A
detailed description of sediment supply for each watershed is described in Section V-Watershed
Assessment. However, below is a brief description.
Piney Run Mainstem: Piney Run watershed sediment supply is low. Sediment is being trapped
by Piney Reservoir, which is located approximately 2 miles upstream of the project area.
Additionally, Piney Run mainstem and the tributaries between Piney Reservoir and the project
area are mostly stable and producing low sediment supplies.
UT6 and UT6e: UT6 and UT6e watersheds have low to moderate sediment loads. Route 32
crosses both tributaries at the upstream ends of the project areas. The roadbed of Route 32, as it
crosses UT6 and UT6e, is significantly elevated and the culverts are undersized for flood flows.
Additionally, the floodplains of UT6 and UT6e, upstream of Route 32 and outside of the project
areas, are low-sloped and wide. These conditions, combined, result in effective sediment
trapping and thus result in a low sediment supply being delivered to UT6 and UT6e.
UT6a: UT6a watershed has a moderate to high sediment supply that is coming from stream bank
erosion upstream of the project area. However, the overall sediment load is low to moderate
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since the drainage area is relatively small (0.76 square miles) and the total stream length,
upstream of the project area, is relatively short (approximately 2,800 feet).
In summary, three out of the four watersheds have low sediment supplies, while one has a
moderate to high sediment load. Therefore, all project areas, except Project Area 15, can have
stream channel dimensions less than bankfull characteristics without resulting in excessive
sediment deposition, when only considering sediment supply. Stream energy and floodplain
availability must also be considered before determining whether a less than bankfull channel is
sustainable over time. For Project Area 15, which has a moderate to high sediment supply, a
restoration solution can be designed that will allow the sediment to deposit at a rate at which
stream stability can be maintained over time. This can occur through the creation of large, well-
vegetated floodplain areas adjacent to the project area.
b. Stream Energy
Stream energy, which can be related to stream slope, varies among the project areas. Generally,
stream channel dimensions of less than bankfull characteristics can be designed for streams with
slopes up to 0.01 ft/ft by minimizing flow depths as flow volumes increase. This can be done by
increasing channel width ratios and providing large floodplain areas adjacent to the stream.
However, a hydraulic analysis is required to demonstrate that stream energy levels associated
with a proposed design will not result in excessive erosion or deposition. The Service did
conduct a hydraulic analysis and the results are described in detail in Section VIII.F.4-
Hydrologic and Hydraulic Analyses. In summary, the existing and proposed stream shear
stresses, velocities and sediment competence demonstrate that the project areas will not have
excessive degradation or aggradation. Therefore, project areas can be designed to stream
channel dimensions of less than bankfull characteristics shown on regional curves.
c. Floodplain Characteristics
Floodplain widths, elevation and shape are critical aspects when developing stream restoration
solutions. An adequate floodplain width and appropriate shape is needed to reduce stream
energy. Width is needed to create storage for flood flows as flow volumes increase. An
appropriate valley shape (e.g., following the fall of the valley versus following the meander
pattern of the stream channel) is needed to reduce flood flow restrictions. A high floodplain
width/depth ratio assists in reducing flood flow depths as flow volume increase, thus reducing
stream and floodplain shear stresses and energy. The hydraulic analysis described above
demonstrates that the floodplain designs associated with the overall proposed stream restoration
solutions will maintain stream and floodplain stability over time. This includes Project Area 15
which was demonstrated to have a moderate to high sediment supply. The proposed floodplain
width of Project Area 15 is adequate enough to allow for a floodplain sediment deposition rate
that will not result in potential adverse impacts.
The floodplain design elevation is influenced by two factors associated with the Piney Run
project. The first are the roadway crossings that were described above in Section VIII.B-
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Constraints. The second is a design objective to excavate the floodplain to historic floodplain
elevations. The roadway crossings will influence streambed design elevations for Project Areas
5, 6 and 7. Raising streambeds will elevate flood levels and increase the potential for roadway
crossings to be overtopped by flood flows. Therefore, the floodplain design elevation cannot be
higher than the existing floodplain elevation for these project areas, but could be designed to a
lower elevation without adverse impacts to the roadway crossings.
To determine the historic floodplain elevation, MDNR contracted with Dorothy Merritts of
Franklin and Marshall College. Trenches were dug at various locations within the existing
floodplain throughout the project area. Data collected from the trenches demonstrated that a
historic floodplain exists in Project Areas 6 and 7. The historic floodplain elevation is
approximately two to three feet lower than the existing floodplain elevation. Additionally, the
data showed that the historic floodplain extends to the valley toe-of-slopes on both sides of the
stream. Locations of the soil trenches and the corresponding data can be found in Appendix F.
Designing a lower floodplain elevation would reduce the potential for flood flows to overtop the
roadway crossings, but could adversely impact existing floodplain natural resources (e.g.,
riparian vegetation, wetlands, etc.). However, this is not a significant issue with the Piney Run
project because almost all of the floodplain areas proposed to be lowered consist primarily of
fallow pasture areas of low ecological value. There are some wetland areas that will be
impacted, but the overall design proposes the creation of wetlands greater in total area than the
existing wetlands. Furthermore, the existing wetlands have low ecological value because of poor
hydrology and vegetation. The proposed wetland areas will have much higher ecological value.
A detailed description of the proposed wetlands and potential impacts are in Section IX-Impacts
to Existing Resources.
d. Stream Channel Characteristics
The analysis of sediment loads, stream energy, and floodplain availability demonstrate that a
stream channel can be designed to channel dimensions of less than bankfull stream characteristic.
This type of stream channel can be either a single or multi-thread channel, or even possibly more
of a wetland complex mosaic across the entire floodplain without a defined stream channel. The
two primary factors that influence which stream channel design can be maintained over time are
valley slope and watershed size.
Reference stream and wetland systems data has been collected by EPR over the past several
years, with the goal of developing a tool to predict channel formation. These data have been
collected primarily from Coastal Plain reference reaches and wetlands, but more recent data has
included inland regions and data from several different states in the Southeastern United States.
Reference streams and flowing wetlands have been surveyed to evaluate the conditions that lead
to channel formation under natural conditions. The analysis of the data, in fact, shows that the
formation of stream channel features is strongly correlated with valley slope and watershed size.
In simplest terms, the energy of flowing water is determined by its velocity and depth.
Formation of a defined stream channel begins when flowing water has sufficient energy to begin
the processes of scour, headcutting, and sediment transport.
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Valley slope is used as a surrogate for flow velocity: the higher the valley slope, the higher the
velocity of flowing water in the stream system during storm events. Drainage area was used as a
surrogate for flow depth and quantity: the higher the drainage area, the higher the volume of
water (and depth of flowing water) for a given storm event. Each surveyed reference
stream/wetland system was classified as either a poorly defined/braided channel or well
defined/single thread channel, based on visual observations during field surveys. Valley slope
and drainage area data are plotted for each surveyed reference reach are provided in Figure 10
(Tweedy, K.L., 2008.) below. The data for the Piney Run design reaches are also plotted for
comparison. Reaches that plot above the transition line tend to be single-thread stream reaches,
whereas reaches that plot below the transition line tend to be braided or flowing wetland reaches.
The further away the reaches plot from the transition line, the more prevalent the channel form.
For all of the Piney Run design reaches, the data plot well above the transition line; therefore, the
prediction is that under natural conditions, single-thread stream channels would be expected for
the Piney Run stream reaches.
Figure 10: Channel formation tool with associated data from Piney Run plotted (Tweedy, K.L., 2008.).
While a single-thread stream channel is expected for the Piney Run stream reaches, the Service
did consider what would happen if no channel was constructed. It is possible to implement a
design approach without a defined stream channel that would allow for a channel to form over
time. However, this would most likely result in considerable erosion and loss of sediment and
pollutants that would be delivered to downstream resources. Adverse impacts would occur to
aquatic species and the habitat needed for the project targeted species could possibly not evolve.
Thus, not actually maximizing the project nutrient and sediment load reduction objectives.
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Therefore, the Service proposes that a single-thread channel be designed for all Piney Run
project reaches.
3. Preferred Plan
Based on the alternative analysis, the Service proposes a combined natural channel design and
valley restoration approach to be applied to the Piney Run Project Areas 3 -7, 9 and 15. This
would involve designing a channel and floodplain system where the proposed channel
dimensions are less than what would be shown on the Piedmont Regional curve (McCandless
and Everett, 2002) and flood flows of less than a bankfull event would access the adjacent
floodplains. The sizing of the design channel dimensions was verified through hydrologic and
hydraulic modeling to ensure that proposed stream reaches would be self-sustaining and would
not aggrade or degrade over time. This approach meets project goals and design objectives,
provides the greatest functional uplift, results in the least amount of adverse impacts to existing
functions, is based on reference conditions and considered low risk.
a. Potential Functional Uplift
This approach, if implemented, will result in functional uplift through Level 5 – Biology.
Assessment parameters in Level 2 - Hydraulics and Level 3 – Geomorphology will be fully
functional while assessment parameters in Level 4 – Physicochemical and Level 5 – Biology will
remain functioning-at-risk but have partial functional uplift. As was stated in the restoration
potential section, restoration of levels 2 and 3 functions are typically the easiest to achieve since
they involve direct, physical manipulation of stream channel dimension, pattern, and profile. The
expected Level 4 uplift will be associated with nutrient reductions. This will occur as a result of
the proposed bank stabilization activities, floodplain reconnection, and creation of extensive
wetland systems. The expected Level 5 - Biology uplift will be associated with improvements to
macroinvertebrate and fish communities through the increase of available in-stream habitat. The
increase of available in-stream habitat is a result of improved bedform diversity functions
associated with Level 3 proposed restoration objectives.
b. Potential Adverse Impacts
Implementation of the preferred approach will involve channel realignment and floodplain
excavation. This type of activity could adversely affect existing riparian vegetation. However,
the majority of the existing riparian vegetation was assessed to have low ecological value and
was rated as Functioning-at-Risk. Therefore, any potential realignment or grading will not
adversely affect the existing riparian vegetation. There are some riparian vegetation areas
though, that do have a higher ecological value. In these areas, the stream reaches have minimal
instability issues and the Service proposes only to implement minor and localized restoration
activities in order to minimize potential adverse impacts.
There are several wetland areas throughout the project area. These wetland areas range in
ecological value from low to high. Existing wetlands with high ecological value are being
avoided and enhanced with proposed plantings. Some of the existing wetlands with low
ecological value will be impacted by the implementation of proposed floodplain areas. However,
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the impacts to these existing wetlands will be self-mitigating through the creation of new wetland
areas that significantly exceed the existing wetland area acres and ecological value. Details of
wetland creation are presented in Section VII-Wetland Assessment.
Some temporary effects may occur during construction. These effects are typical of stream
restoration projects regardless of which design approach is implemented and generally include
displacement of aquatic species and increases in turbidity. To reduce these potential impacts, the
Service recommends a construction sequence where new channel construction occurs first and
then connection to the existing channel occurs. Specific potential adverse impacts for each
project area are presented below in Section VIII.F.2-Proposed Project Area Descriptions and
summarized in Section IX-Impacts to Existing Resources.
c. Uncertainty and Risk
Project uncertainty and risk is used to determine the likelihood of the project to succeed in
achieving the stated goals and objectives, as well as the consequences if they are not met. There
are three classes of uncertainty: 1) uncertainty of knowledge, 2) uncertainty about quantities and
3) uncertainty about models (Yoe, 1996). The components of risk are then split into two parts:
1) risk evaluation (i.e., how risky is a situation?) and 2) risk management (i.e., what should be
done about the risk?) (Yoe, 1996).
Uncertainty and risk are first explored when considering the level of detail in the existing
conditions assessment. Increases in uncertainty and risk can occur with limited or inaccurate
documentation of existing resource conditions. To reduce uncertainty in knowledge and
quantities, the Service developed a comprehensive and detailed existing conditions data set by
conducting rapid function-based watershed and reach level assessments of the entire project area
and detailed function-based assessments of representative stream reaches (Sections III-Project
Process Methodology, V-Watershed Assessment and VI-Reach Level Assessment). Additionally,
the Service documented historic stream conditions and determined what stream conditions would
naturally form and be self-maintaining by current day watershed and reach level existing
conditions. This understanding was drawn from the channel evolution evaluation conducted as
part of the reach level function-based assessment. The channel evolution evaluation not only
describes what stream condition could be maintained but it also describes what evolution must
occur before quasi-equilibrium can be achieved. This is important because it influences the
design objectives (discussed below) and level of restoration required. A stream that is near quasi-
equilibrium may only require some localized restoration activities to meet design goals and
objectives versus a stream that is highly unstable. A highly unstable stream would most likely
need to undertake significant restoration activities to meet design goals and objectives. A greater
level of restoration effort leads to a greater potential for higher project uncertainty and risk.
However, the Service has minimized project uncertainty and risk with a detailed understanding
of existing conditions and through the development of suitable and achievable restoration design
goals and objectives.
Uncertainty and risk is then addressed in the project design goals and objectives. Project goals
and objectives that are poorly defined and/or overly ambitions create uncertainty in project
expectations. Therefore, critical evaluation of project success requires specific, well defined, and
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measurable design objectives to be identified early. Therefore, the Service developed measurable
and quantifiable design objectives for each Piney Run project area, which are listed in Section
VIII.D-Design Objectives.
The ability to meet design objectives is also influenced by site suitability. As stated above,
stream functions that would naturally form and be maintained over time would have low
uncertainty and risk, in comparison to a high uncertainty and risk with functions that would not
naturally form and be maintained. Along with the assessment of historic conditions and channel
evolution, the Service used a reference reach design approach in developing design criteria to
reduce site suitability uncertainty and risk. The concept of a reference reach design approach is
to duplicate channel dimensions, pattern and profile of a stable, self-maintaining stream reach
within a proposed project area. It involves collecting stream reach data from stable streams in
similar watershed conditions as the proposed project watershed and developing design criteria
specific to the proposed project area. The Service has collected reference data from appropriate
stable stream reaches and developed design criteria for each project area. A more detailed
description of how design criteria were developed is in Section VIII.F.1-Design Criteria and
project reach specific design criteria are located in Appendix G.
The final component of project uncertainty surrounds the restoration design modeling
verification. The ability of a model to predict accurate conditions influences uncertainty.
Decreases in uncertainty can be achieved through using models that have proven capabilities in
predicting actual conditions. Therefore, the Service used HEC HMS and HEC RAS to model
hydrologic and hydraulic project conditions since these models are the most widely accepted and
used models. The Service calibrated the HEC HMS by using 12 years of collected flow data
from Piney Reservoir and calibrated the HEC RAS by using field collected roughness data and
U. S. Geological Service flow regression equations (a standard practice). The Service used these
models to test and verify stream stability of the proposed stream design. Specifically, the Service
evaluated stream energy to determine if the proposed stream channel dimensions, profile, and
pattern would not aggrade or degrade over time. The results of the modeling analysis, shown in
Section VIII.F.4-Hydrologic and Hydraulic Analyses, demonstrate that the proposed design will
be maintained over time.
The final step associated with risk is managing the potential risk. In any project, there will
always be unpredictable natural and/or anthropogenic disturbances that could influence the
performance of a proposed restoration project. The Service has taken steps towards reducing
unpredictable uncertainty and risk. For example, the Service used local and state planning
documents to predict potential future anthropogenic disturbances, described in Section V-
Watershed Assessment. Additionally, the Service has proposed the creation of extensive
floodplain areas to address any potential episodic natural events (e.g., extreme storm events) that
could impact project effectiveness. However, it is impossible to predict all potential future
actions that could affect the proposed restoration project, but risk management is a way to
address the uncertainty of future disturbances. Risk management can be incorporated in the
maintenance/adaptive management and monitoring plans. Therefore, the Service recommends
that a maintenance and monitoring plan be developed, that describes how the proposed
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restoration project shall be monitored, when maintenance will be required, and who is
responsible for the monitoring and maintenance.
The Service considers the Piney Run Stream restoration project to be low uncertainty and risk
because of the comprehensive, detailed existing conditions data set; suitable and quantifiable
design objectives; reference reach based design criteria, design modeling verification, restoration
level of effort, and the proposed monitoring and maintenance plan. Bottom line, the Service is
proposing a stream restoration design that would naturally form and be self-maintaining over
time, given current day Piney Run watershed and reach level existing conditions.
d. Implementation Costs
The implementation of Phase 1 Piney Run restoration project will include planting and wetland
enhancement along nearly 4.23 miles of stream and restoration lengths of over 16,000 linear feet.
Given the size and scope of this effort, the implementation, efficiency and cost-effectiveness of
the project is dependent upon a variety of construction-based challenges.
The Piney Run project area is owned and managed by entities of the state of Maryland as well as
Carroll County. Access is relatively unrestricted throughout the project site and does not pose to
be a significant problem. However, due to the scale of the project, a significant amount of access
points are required to efficiently work on restoration areas. Currently, the design proposes
approximately seven access points. These locations can be found on the Erosion and Sediment
Control sheets within the construction plan set. Access points were chosen to minimize the
amount of impacts to the existing natural resources and also provide reasonably close access to
restoration areas. Because the project area is either agriculture or wooded, it is presumed that
access will be adequate throughout the construction term. Additionally, since preferential access
is readily available and has not been limited, construction will be more efficient, lessening
overall construction costs.
The scale of the Piney Run restoration poses its own set of challenges during the implementation
phase. As mentioned previously, the Piney Run watershed is designated as a Use Class III which
restricts in channel work from October 1 through April 1. This limits in channel construction to 6
months per year. Due to this, the site area, and overall project scope, it is likely that the term of
the construction could run upwards of three construction “seasons” based on the selected
contractor and available resources. Since it is likely that it will take multiple seasons, this will
negatively impact overall cost due to the mobilization / demobilization efforts that will have to
take place more than once.
The final construction plan set calls for the excavation of 63,400 cubic yards of earthen material.
Most of this material is being generated from the lower portion of UT6 and adjacent to the main
stem of Piney Run. While it is usually the goal of any excavation project to balance cut/fill
volumes, due to the design methodology chosen in these locations, the excavation and excess
volumes are unavoidable. It has been determined that nearly 20,000 cubic yards will be reused
but a balance of 43,800 cubic yards will remain as excess or “spoil” material. The removal and
relocation of this excess material accounts for nearly 30% of the overall costs of the project,
which makes it the most substantial cost of the restoration effort.
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A variety of in-stream structures were used for the restoration of Piney Run and its tributaries.
These structures utilize items naturally found on the landscape, such as rock and logs to promote
stability within the stream channel and valley floor. It is not anticipated that any large quantity of
suitable structure rock will be located on site, and therefore must be imported from local
quarries. Due to this fact, the design team proposed a mixed structure ensemble that utilizes
woody material such as trees and limbs to serve similar purposes as well as promote additional
habitats within the structures. While there is not an abundance of trees to be cleared on the site,
the costs associated with this woody material are usually less than that of stone. With this being
said, it also offers the opportunity to reuse trees that may need to be removed for construction
access or floodplain grading. Utilizing all available material on-site minimizes necessary import
costs and the design team sought those opportunities out where available.
An extensive planting plan has also been developed for the restoration of Piney Run and its
tributaries. This plan seeks to enhance existing riparian habitat but also create robust riparian
conditions along the areas of newly restored stream. Again, the costs associated with this
planting effort are unavoidable and also crucial to the success of the project. The establishment
of a dense riparian corridor instantly stabilizes loose soils and instantly provides filtration
properties to overland flows. The design team specifically selected appropriate riparian plants
that will establish quickly and recommended quantities that will result in the creation of a dense
riparian habitat.
There are many additional tasks that play into the construction costs associated with this project,
including labor costs and state and local permitting requirements, however, those noted above
are most critical. Based on the construction plan set as well as historic project implementation
cost data compiled by the design team, it is estimated that this project will cost approximately
six million dollars to complete. A more detailed breakdown of the project costs by reach can be
found in Appendix H.
F. DESIGN DEVELOPMENT
The Piney Run stream restoration project offered the unique opportunity to employ a variety of
ecologic restoration design methodologies to properly address areas of instability or lacking
habitat while using location appropriate restoration measures to meet the project goals of the
partners.
While not exclusive, the project generally uses Natural Channel Design (NCD) principals
throughout much of the project area. NCD uses form and process to develop stream restoration
designs. Form is the structural features of a stream and includes channel dimensions, pattern and
profile. It is based on reference stream conditions that are the same stream type, valley type,
vegetation type, and bed material. Process is the analytical assessment of a design. Hydraulic
and sediment calculations are conducted to determine the potential stability of the design.
Adjustments are made to the design based on the results of the analytical assessment and then the
design is re-assessed. This iterative process continues until the analytical assessment shows that
the design will be self-maintaining and that the channel dimensions, pattern and profile match
reference conditions.
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A variation of the NCD process was also used to better promote floodplain connection and
complexity. Rigorous hydraulic modeling was conducted to reduce channel dimension as much
as possible to safely convey sediments and flows while allowing higher frequency storm flows to
reach complex wetland areas. This particular variation is found lower in the drainage area where
a larger floodplain is present. These areas were found to have relic floodplains identified below
the existing floodplain and excavation was proposed to reach the historic floodplain soils to
return these areas to their historic state.
In this section, the Service documents how the NCD process was applied and modified to the
project areas. It contains design criteria, proposed plan, in-stream structures, hydrologic and
hydraulic assessment, sediment transport assessment, and proposed vegetation plans.
1. Design Criteria
Design criteria was compiled by standardizing existing channel plan, profile and dimension of
design criteria developed by the Service and other sources (Harman et al., 2011; Flores, 2011;
Hay, 2006; NRCS, 2007; and Leopold et al, 1992). In addition, the Service was able to locate
stable riffles throughout the project area, which were free to adjust and had good bankfull
indicators., Cross sections were taken at these riffles to model the design geometry criteria. The
measurements from these cross sections were verified and extrapolated using the regional curve
calculations, resistance equations, and natural channel design reference ratios for Rosgen C4 and
B4 stream types, described below in Section VIII.F.4-Hydrologic and Hydraulic Analyses.
Additionally, MDNR contracted with Dorothy Merritts of Franklin and Marshall College to
determine the historic floodplain elevation, which was used to set the proposed floodplain
elevation. The design criteria are located in Appendix G – Design Criteria.
2. Proposed Project Area Descriptions
The overall Piney Run Stream restoration design has 16 individual project areas. A brief
description of each project area design, along with potential uplift and adverse impacts is
provided below. Details of proposed project area plans can be found in the Piney Run Stream
Restoration Design Plan Set.
a. Project Area 1
Project area 1 only requires corrective actions in isolated areas of instability. The existing and
proposed design stream type for Project Area 1 is a Rosgen B4. A Rosgen B4 stream type is a
non-meandering stream that dissipates energy vertically within the bed of the channel and has a
floodplain as small as 1.4 times its bankfull width.
The Service has determined that Project Area 1 is generally stable and still connected to its
floodplain, so it does not require any additional action to meet the Level 2 –Hydraulic design
goal of floodplain reconnection / more frequent inundation.
Only minor stability fixes are required to achieve the Level 3 – Geomorphology lateral stability
and sediment load reduction design goals. The Service plans to address isolated instabilities
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within the stream channel while maintaining existing plan form, profile and dimension. To
promote bedform diversity and lateral stability, in-stream structures will be installed to promote
pool scour and glide and riffle formation while protecting adjacent banks. While proper plan
form is important, the Service has recognized that stability cannot be achieved without the proper
riparian conditions. The Service has proposed bio-engineering and dense riparian planting that
will be done in association with the isolated stability fixes.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization. Level 5 – Biology design objectives of increasing
macroinvertebrate and fish population diversity and densities will be met primarily through the
bedform diversity improvements and in-stream structures.
Areas adjacent to Project Area 1 consist primarily of mature mixed hardwood forests, as
described in Section VI-Reach Level Assessment. Therefore, the potential adverse impacts,
other than those described above in Section VIII.E.3.b-Potential Adverse Impacts, would be
temporary access requirements through the floodplain and light damage to the existing riparian
corridor. These impacts would be mitigated accordingly.
b. Project Area 2
Similarly to Project area 1, Project Area 2 only requires corrective actions in isolated areas of
instability. The existing and proposed design stream type for Project Area 2 is a Rosgen B4. A
Rosgen B4 stream type is a non-meandering stream that dissipates energy vertically within the
bed of the channel and has a floodplain as small as 1.4 times its bankfull width.
The Service has determined that Project Area 2 is generally stable and is still generally
connected to its floodplain and does not require any additional action to meet the Level 2 –
hydraulic design goal of Floodplain reconnection / more frequent inundation. Additionally, the
upstream most portion is well armored by natural stone as well as placed stone from an adjacent
utility easement.
Only minor stability fixes are required to achieve the Level 3 – Geomorphology lateral stability
and sediment load reduction design goals, the Service plans to address isolated instabilities
within the stream channel maintain existing planform, profile and dimension. To promote bed
form diversity and lateral stability, in-stream structures will be installed to promote pool scour
and glide and riffle formation while protecting adjacent banks. While proper plan form is
important, the Service has recognized that stability cannot be achieved without the proper
riparian conditions. The Service has proposed bio-engineering and dense riparian planting that
will be done in association with the isolated stability fixes.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primary
through the bank stabilization. Level 5 – Biology design objectives of increasing
macroinvertebrates and fish population diversity and densities will be met primary through the
bedform diversity improvements and in-stream structures.
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Areas adjacent to Project Area 2 consist primarily of mature mixed hardwood forests that slowly
open up to relic pasture and grass meadow, as described in Section VI-Reach Level Assessment.
Therefore, the potential adverse impacts, other than those described above in Section VIII.E.3.b-
Potential Adverse Impacts, would be temporary access requirements through the floodplain and
light damage to the existing riparian corridor. These impacts would be mitigated accordingly.
c. Project Area 3
The proposed design stream type for Project Area 3 is a modified Rosgen C4. A modified
Rosgen C4 stream type is a meandering stream that dissipates energy laterally across the
floodplain but has channel dimensions less than what would be shown in the Piedmont Regional
Curve (McCandless and Everett, 2002). Additional supporting information describing how the
proposed cross sectional area was derived is presented in Section VIII.F.4- Hydrologic and
Hydraulic Analyses. This approach will allow the Service to achieve the Level 2 - Hydraulic
design goal of connecting flood flows of less than bankfull flows to the floodplain.
Currently, the project area is disconnected from its floodplain and needs to be reconnected to
allow for adequate energy dissipation and to allow for more frequent out of bank flow events.
The Service proposes a moderate channel lift coupled with excavation of a new floodplain. The
proposed elevation of the floodplain is targeted to rehydrate existing wetlands as well as limit the
amount of necessary excavation and impact to adjacent resources. Along with the channel
relocation and floodplain excavation, some areas of the existing channel will be allowed to
remain open, thus providing vernal pools, as additional back water habitat for fish and
amphibians. This design concept will allow the Service to achieve the Level 2 - Hydraulic design
goal of reconnecting to the historic floodplain and maximizing valley width. Furthermore, the
proposed floodplain areas will consist of a wetland mosaic to meet the Level 2 - Hydraulic
design goal of increasing floodplain complexity and eliminating concentrated flows.
To achieve the Level 3 – Geomorphology lateral stability and sediment load reduction design
goals, the Service plans to re-align the stream channel to create meanders and belt widths that
would promote increased lateral stability. The proposed alignment was placed to minimize over
excavation and to avoid potential conflicts with the existing sewer line. To promote bed form
diversity, in-stream structures will be installed to promote pool scour and glide and riffle
formation while protecting adjacent banks. While proper plan form is important, the Service has
recognized that stability cannot be achieved without the proper riparian conditions. The Service
has proposed dense wetland riparian plantings that will extend beyond the limits of the design
belt width to increase the stability of the system.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and the extensive wetland areas. Level 5 – Biology design
objectives of increasing macroinvertebrate and fish population diversity and densities will be met
primarily through the bedform diversity improvements, in-stream structures, and the extensive
wetland areas.
Areas adjacent to Project Area 3 consist primarily of old fallow fields of low ecological value, as
described in Section VI-Reach Level Assessment. Therefore, the only potential adverse impacts,
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other than the ones described above in Section VIII.E.3.b-Potential Adverse Impacts, are to 0.72
acres of existing, low ecological value wetland areas; 0.53 acres of which are temporary impacts.
The impacts to these existing wetlands will be self-mitigating through the creation of new
wetland areas that significantly exceed the existing wetland area in acres and ecological value.
Details of wetland creation are presented in Section VII-Wetland Assessment. Exact figures and
locations of wetland impacts are referenced in Section IX-Impacts to Existing Resources and
Appendix L.
d. Project Area 4
Like Project Area 3, the proposed design stream type for Project Area 4 is a modified Rosgen
C4. A modified Rosgen C4 stream type is a meandering stream that dissipates energy laterally
across the floodplain but has channel dimensions less than what would be shown in the Piedmont
Regional Curve (McCandless and Everett, 2002). Additional supporting information describing
how the proposed cross sectional area was derived is presented in Section VIII.F.4-Hydrologic
and Hydraulic Analyses. This approach will allow the Service to achieve the Level 2 - Hydraulic
design goal of connecting flood flows of less than bankfull flows to the floodplain.
Currently, the project area is disconnected from its floodplain and needs to be reconnected to
allow for adequate energy dissipation and to allow for more frequent out of bank flow events.
The Service proposes a moderate channel lift coupled with excavation of a new floodplain. The
proposed elevation of the floodplain is targeted to rehydrate existing wetlands as well as limit the
amount of necessary excavation and impact to adjacent resources. Along with the channel
relocation and floodplain excavation, some areas of the existing channel will be allowed to
remain open, thus providing vernal pools as additional back water habitat for fish and
amphibians. This design concept will allow the Service to achieve the Level 2 - Hydraulic design
goal of reconnecting to the historic floodplain and maximizing valley width. Furthermore, the
proposed floodplain areas will consist of a wetland mosaic to meet the Level 2 - Hydraulic
design goal of increasing floodplain complexity and eliminating concentrated flows.
To achieve the Level 3 – Geomorphology lateral stability and sediment load reduction design
goals, the Service plans to re-align the stream channel to create meanders and belt widths that
would promote increased lateral stability. The proposed alignment was placed to minimize over
excavation and to avoid potential conflicts with the existing sewer line. To promote bed form
diversity, in-stream structures will be installed to promote pool scour and glide and riffle
formation while protecting adjacent banks. While proper plan form is important, the Service has
recognized that stability cannot be achieved without the proper riparian conditions. The Service
has proposed dense wetland riparian plantings that will extend beyond the limits of the design
belt width to increase the stability of the system.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and the extensive wetland areas. Level 5 – Biology design
objectives of increasing macroinvertebrate and fish population diversity and densities will be met
primarily through the bedform diversity improvements, in-stream structures, and the extensive
wetland areas.
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Areas adjacent to Project Area 4 consist primarily of old fallow fields of low ecological value, as
described in Section VI-Reach Level Assessment. Therefore, the only potential adverse impacts,
other than the ones described above in Section VIII.E.3.b-Potential Adverse Impacts are to 0.56
acres of existing, low ecological value wetland areas; 0.49 acres of which are temporary impacts.
The impacts to these existing wetlands will be self-mitigating through the creation of new
wetland areas that significantly exceed the existing wetland area in acres and ecological value.
Details of wetland creation are presented in Section VII-Wetland Assessment. Exact figures and
locations of wetland impacts are referenced in Section IX-Impacts to Existing Resources and
Appendix L.
e. Project Area 5
The proposed stream type design for Project Area 5 is a modified Rosgen B4c. A Rosgen B4c
stream type is a moderately entrenched stream with low sinuosity. The sewer alignment along
the left bank and property line along the right bank are constraints that prevent the ability to
achieve the meander ratio needed to create a C4 stream type. Channel realignment is mainly
limited from a downstream bridge constraint. Currently, the stream enters the culvert under
Slacks Road off-center. Therefore, the channel will be realigned to center the flow through the
Slacks Road culvert and restore a limited meander pattern due to human constraints. Channel
dimensions will be sized smaller than would be expected in the appropriate regional curve to
achieve greater floodplain connectivity (described in Section VIII.F.4-Hydrologic and Hydraulic
Analyses).
Currently, the project area is disconnected from its floodplain and needs to be reconnected to
allow for adequate energy dissipation and to allow for more frequent out of bank flow events. A
Rosgen Priority Level 2 approach will be used to excavate a floodplain bench to restore
connectivity to the historic floodplain elevation and provide more frequent floodplain inundation.
The floodplain bench will be approximately two to three feet lower than the existing floodplain
elevation and extend slightly beyond the meander width of the proposed channel. Excavating the
floodplain elevations to the valley toe-of-slopes will allow the Service to achieve the Level 2 -
Hydraulic design goal of reconnecting to the historic floodplain, maximizing valley width, and
connecting flood flows of less than bankfull flows to the floodplain. Furthermore, the proposed
floodplain areas will consist of a wetland mosaic to meet the Level 2 - Hydraulic design goal of
increasing floodplain complexity and eliminating concentrated flows.
The achievement of Level 3 – Geomorphology lateral stability and sediment load reduction
design goals in a B4c channel requires more structures to be placed to ensure stability from
energy dissipation in small scour pools as less energy is dissipated through a meandering plan
form. Bank stability will be provided from the installation of rock cross vanes and rock/log j-
hooks to center the flow velocities through the middle of the channel, as well as through robust
stream bank planting that will provide stabilization through root establishment.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and the extensive wetland areas. Level 5 – Biology design
objectives of increasing macroinvertebrate and fish population diversity and densities will be met
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primarily through the bedform diversity improvements, in-stream structures, and the extensive
wetland areas.
Areas adjacent to Project Area 5 consist primarily of old fallow fields of low ecological value, as
described in Section VI-Reach Level Assessment. While there are no existing wetlands within
Project Area 5, creation of new wetland areas are proposed that will result is significantly
functional uplift. Details of wetland creation are presented in Section VII-Wetland Assessment.
f. Project Area 6
The proposed design stream type for Project Area 6 is a modified Rosgen C4. A modified
Rosgen C4 stream type is a meandering stream that dissipates energy laterally across the
floodplain but has channel dimensions less than what would be shown in the Piedmont Regional
Curve, similar to project area 5 and described in Section VIII.F.4-Hydrologic and Hydraulic
Analyses. Constraints from the sewer alignment in Project Area 5 continue along the left bank in
Project Area 6, however, an open floodplain on the right bank will be created and planted for
emergent wetland creation where the existing channel is abandoned during realignment.
Currently, the project area is disconnected from its floodplain and needs to be reconnected to
allow for adequate energy dissipation and to allow for more frequent out of bank flow events. A
Rosgen Priority 2 restoration approach will excavate a bankfull bench along both sides of the
stream at an elevation close to the historic floodplain. The bench will extend beyond the meander
width of the realigned channel and incorporate portions of the existing channel to be filled. The
floodplain will be approximately two to three feet lower than the existing floodplain. This
reconnection will allow the Service to achieve the Level 2 - Hydraulic design goal of
reconnecting to the historic floodplain, maximizing valley width, and connecting flood flows of
less than bankfull flows to the floodplain. Furthermore, the proposed floodplain areas will
consist of a wetland mosaic to meet the Level 2 - Hydraulic design goal of increasing floodplain
complexity and eliminating concentrated flows.
To achieve the Level 3 – Geomorphology lateral stability and sediment load reduction design
goals, the Service plans to re-align the stream channel to create meanders and belt widths that
would promote increased lateral stability. The proposed alignment was placed to avoid potential
conflicts with the existing sewer line and to provide a more stable realignment plan form with the
confluence at the Piney Run mainstem. To promote bedform diversity, in-stream structures will
be installed to promote pool scour and glide and riffle formation while protecting adjacent banks.
The placement of hardened in-stream structures will provide grade control and protection for
infrastructure, while wooden structures will provide bank protection and habitat for target
species.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and the extensive wetland areas. Level 5 – Biology design
objectives of increasing macroinvertebrate and fish population diversity and densities will be met
primary through the bedform diversity improvements, in-stream structures and the extensive
wetland areas.
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Areas adjacent to Project Area 6 consist primarily of old fallow fields of low ecological value, as
described in Section VI-Reach Level Assessment. Therefore, the only potential adverse impacts,
other than the ones described above in Section VIII.E.3.b-Potential Adverse Impacts, are to 0.27
acres of existing, low ecological value wetland areas; 0.21 acres of which are temporary impacts.
The impacts to these existing wetlands will be self-mitigating through the creation of new
wetland areas that significantly exceed the existing wetland area in acres and ecological value.
Details of wetland creation are presented in Section VII-Wetland Assessment. Exact figures and
locations of wetland impacts are referenced in Section IX-Impacts to Existing Resources and
Appendix L.
g. Project Area 7
The proposed design stream type for Project Area 7 is a modified Rosgen C4. A modified
Rosgen C4 stream type is a meandering stream that dissipates energy laterally across the
floodplain but has channel dimensions less than what would be shown in the Piedmont Regional
Curve (McCandless and Everett, 2002). The most critical factor influencing the Piney Run
proposed channel dimensions is Piney Reservoir, upstream of the project area. The flow
operation of Piney Run Reservoir significantly reduces flood flows reaching the project area.
Thus, the proposed Piney Run channel cross sectional area is 45 sq. ft. versus 127 sq. ft. as
shown on the Piedmont Regional Curve. Additional supporting information describing how the
proposed cross sectional area was derived is presented in Section VIII.F.4-Hydrologic and
Hydraulic Analyses.
Currently, the project area is disconnected from its floodplain and needs to be reconnected to
allow for adequate energy dissipation and to allow for more frequent out of bank flow events.
Since the elevation of the streambed cannot be increased due to infrastructure (i.e., Slacks Road
bridge crossing), the Service proposes excavation of a new floodplain. The elevation of the
floodplain is based on the historic floodplain analysis conducted by Dorothy Merritts, at Franklin
and Marshall College. It will be approximately one to two feet lower than the existing floodplain
elevation and extend to the valley toe-of-slopes on both sides of the stream. Excavating the
floodplain down to the historic floodplain elevations and out to the valley toe-of-slopes will
allow the Service to achieve the Level 2 - Hydraulic design goal of reconnecting to the historic
floodplain, maximizing valley width, and connecting flood flows of less than bankfull flows to
the floodplain. Furthermore, the proposed floodplain areas will consist of a wetland mosaic to
meet the Level 2 - Hydraulic design goal of increasing floodplain complexity and eliminating
concentrated flows.
To achieve the Level 3 – Geomorphology lateral stability and sediment load reduction design
goals, the Service plans to re-align the stream channel to create meanders and belt widths that
would promote increased lateral stability. The proposed alignment was placed to take advantage
of the stability provided by the few large existing trees and to avoid potential conflicts with the
existing sewer line. To promote bed form diversity, in-stream structures will be installed to
promote pool scour, and glide and riffle formation while protecting adjacent banks. Additionally,
where feasible, the Service intercepted the historic gravel layer to promote bed stability and
increase hyporheic zone functions. While proper plan form is important, the Service has
recognized that stability cannot be achieved without the proper riparian conditions. The Service
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has proposed dense wetland riparian plantings that will extend beyond the limits of the design
belt width to increase the stability of the system.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and the extensive wetland areas. Level 5 – Biology design
objectives of increasing macroinvertebrate and fish population diversity and densities will be met
primarily through the bedform diversity improvements, in-stream structures, and the extensive
wetland areas.
Areas adjacent to Project Area 7 consist primarily of old fallow fields of low ecological value, as
described in Section VI-Reach Level Assessment. Therefore, the only potential adverse impacts,
other than the ones described above in Section VIII.E.3.b-Potential Adverse Impacts, are to 1.97
acres of existing, low ecological value wetland areas; 1.59 acres of which are temporary impacts.
The impacts to these existing wetlands will be self-mitigating through the creation of new
wetland areas that significantly exceed the existing wetland area in acres and ecological value.
Details of wetland creation are presented in Section VII-Wetland Assessment. Exact figures and
locations of wetland impacts are referenced in Section IX-Impacts to Existing Resources and
Appendix L.
h. Project Area 8
Project Area 8 is a continuation of the Piney Run mainstem and the design stream type for this
section continues the modified Rosgen C4 previously discussed in Project Area 7. However, a
significant portion of this project area is fully forested and instability problems are only localized
along short bank segments. Therefore, localized work was proposed to reduce significant impacts
to existing tree stands. This work includes the installation of three rock cross-vanes and toe wood
along outside meanders of unstable banks to promote bank stabilization. The design goals in
Level 3 – Geomorphology of lateral stability and sediment load reduction will be achieved
through the installation these in-stream structures. Furthermore, the installation of the rock cross-
vanes will promote pool scour, and glide and riffle formation to increase bedform diversity.
Areas adjacent to Project Area 8 consist of fully forested areas, as described in Section VI-Reach
Level Assessment. Construction will be extremely focused to limit removal of trees.
Additionally, reconnection of the floodplain with frequent inundation events will help promote
the development of forested wetlands.
i. Project Area 9
The proposed design stream type for Project Area 9 is a Rosgen B4. A Rosgen B4 stream type is
a non-meandering stream that dissipates energy vertically within the bed of the channel and has a
floodplain as small as 1.2 times its bankfull width. The most critical factor influencing the
Project Area 9 is the concrete culvert that conveys flows under MD Route 32. Years of
concentrated high volume flows have hampered the upstream portion of Project Area 9 and
severely eroded the banks. Along with historic incision, this has disconnected the reach from its
floodplain. The design aims to create a stream system that dissipates its energy vertically, rather
than laterally in order to minimize necessary floodplain width for stability.
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Currently, the project area is disconnected from its floodplain and some floodplain needs to be
created to allow for adequate energy dissipation and to allow for more frequent out of bank flow
events. The Service proposes installing in-channel grade control structures along with light
excavation of a new floodplain, as well as some channel realignment. Doing so will allow the
Service to achieve the Level 2 - Hydraulic design goal of reconnecting the channel to an
available floodplain.
To achieve the Level 3 – Geomorphology lateral stability and sediment load reduction design
goals, the Service plans to slightly re-align the stream channel and install grade control structures
to promote increased lateral stability. To promote bedform diversity, in-stream structures will be
installed to promote pool scour, and glide and riffle formation while protecting adjacent banks.
While proper plan and profile form is important, the Service has recognized that stability cannot
be achieved without the proper riparian conditions. The Service has proposed dense upland
riparian plantings to increase the stability of the system.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and planting. Level 5 – Biology design objectives of increasing
macroinvertebrate and fish population diversity and densities will be met primarily through the
bedform diversity improvements and in-stream structures.
Areas adjacent to Project Area 12 consist primarily of mixed hardwood upland areas of low
ecological value, as described in Section VI-Reach Level Assessment. Therefore, the only
potential adverse impacts, other than the ones described above in Section VIII.E.3.b-Potential
Adverse Impacts, are to 0.25 acres of existing, low ecological value mixed hardwood upland
areas that may be damaged from access. Impacts will be mitigated accordingly.
j. Project Area 10
Project area 10 will remain undisturbed with the exception of riparian planting along its banks
and into the adjacent uplands.
k. Project Area 11
Project area 11 only requires corrective actions in isolated areas of instability. The existing and
proposed design stream type for Project Area 11 is a Rosgen B4. A Rosgen B4 stream type is a
non-meandering stream that dissipates energy vertically within the bed of the channel and has a
floodplain as small as 1.4 times its bankfull width.
The Service has determined that Project Area 11 is generally stable and still connected to its
floodplain, so it does not require any additional action to meet the Level 2 – Hydraulic design
goal of floodplain reconnection/more frequent inundation.
Only minor stability fixes are required to achieve the Level 3 – Geomorphology lateral stability
and sediment load reduction design goals. The Service plans to address isolated instabilities
within the stream channel while maintaining existing plan form, profile and dimension. To
promote bedform diversity and lateral stability, in-stream structures will be installed to promote
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pool scour and glide and riffle formation while protecting adjacent banks. While proper plan
form is important, the Service has recognized that stability cannot be achieved without the proper
riparian conditions. The Service has proposed bio-engineering and dense riparian planting that
will be done in association with the isolated stability fixes.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization. Level 5 – Biology design objectives of increasing
macroinvertebrate and fish population diversity and densities will be met primarily through the
bedform diversity improvements and in-stream structures.
Areas adjacent to Project Area 11 consist primarily of mature mixed hardwood forests, as
described in Section VI-Reach Level Assessment. Therefore, no adverse impacts, other than the
ones described above in Section VIII.E.3.b-Potential Adverse Impacts exist here.
l. Project Area 12
The proposed design stream type for Project Area 12 is a Rosgen B4c. Rosgen B4c stream type
is a non-meandering stream that dissipates energy vertically within the bed of the channel and
has a floodplain as small as 1.4 times its bankfull width.
Currently, the project area is disconnected from its floodplain and needs to be reconnected to
allow for adequate energy dissipation and to allow for more frequent out of bank flow events.
The Service proposes lifting the channel bed, light excavation of a new floodplain, as well as
some channel realignment. Doing so will allow the Service to achieve the Level 2 - Hydraulic
design goal of reconnecting to the historic floodplain and maximizing valley width.
To achieve the Level 3 – Geomorphology lateral stability and sediment load reduction design
goals, the Service plans to re-align the stream channel to create meanders and belt widths that
would promote increased lateral stability. The proposed alignment was placed to take advantage
of the stability provided by the few large existing trees. To promote bedform diversity, in-stream
structures will be installed to promote pool scour, and glide and riffle formation while protecting
adjacent banks. While proper plan form is important, the Service has recognized that stability
cannot be achieved without the proper riparian conditions. The Service has proposed dense
wetland riparian plantings that will extend beyond the limits of the design belt width to increase
the stability of the system.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and the extensive wetland areas. Level 5 – Biology design
objectives of increasing macroinvertebrate and fish population diversity and densities will be met
primarily through the bedform diversity improvements, in-stream structures, and the extensive
wetland areas.
Areas adjacent to Project Area 12 consist primarily of mixed hardwood upland areas of low
ecological value, as described in Section VI-Reach Level Assessment. Therefore, the only
potential adverse impacts, other than the ones described above in Section VIII.E.3.b-Potential
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Adverse Impacts, are to 0.25 acres of existing, low ecological value mixed hardwood upland
areas.
m. Project Area 13
Project Area 13 contains approximately 600 feet of small stream that drains a small spring seep.
No structures or channel work are proposed in the project area. Riparian planting along the banks
of the small spring seep channel will provide lateral stability through vegetation establishment
and help the service achieve Level 3 – Geomorphology design goals of increased riparian buffer.
Minor channel realignment at the downstream end of the channel will redirect flow into a
proposed wetland area to increase water retention time for improved sediment and nutrient
reduction before draining into the realigned UT6 channel. Changes to increase retention time and
alter the confluence along a more stable flow pattern will allow the Service to achieve additional
Level 3 – Geomorphology goals of increased sediment and nutrient retention and increased
lateral stability.
n. Project Area 14
Project Area 14 has two separate streams. There is the mainstem unnamed tributary (labeled as
UT6a Upper) and another unnamed stream (labeled UT6a1) that is a tributary toUT6a . The
proposed design stream type for UT6a is a Rosgen B4c. A Rosgen B4c has a steeper slope which
creates more energy, but less meander patterns that would be capable of dissipating that energy.
The project area runs through a confined valley which limits the possible meander width that
would allow the design to be a Rosgen C4 type stream. To compensate for this, several rock/log
j-hooks will be placed along the meander bends of UT6a in order to dissipate energy through the
developed scour pools. Along UT6a1, channel adjustments for bank repair and pool development
are only being made to a small section of the stream, approximately 50 feet in length. This
includes the installation of a constructed riffle with a cross vane to provide grade control.
Overall, the project area utilizes a Rosgen Priority Level 3 restoration approach, which involves
the excavation of a floodplain bench to promote floodplain inundation. The bank height ratio is
equal to 1 and the cross sectional area is slightly less than the regional curve prediction to help
promote the floodplain inundation and meet Level 2 – Hydraulics design goals.
Level 3 – Geomorphology increased bedform diversity design goals will be met through the
installation of in-stream structures and development of associated scour pools. The in-stream
structures will also improve lateral stability and provide reduced sediment loads by directing the
stream flow away from eroding banks. In addition, the Service has recognized that stability
cannot be achieved without the proper riparian conditions. The Service has proposed dense
wetland riparian plantings that will extend beyond the limits of the design belt width to increase
the stability of the system.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and the extensive wetland areas. Level 5 – Biology design
objectives of increasing macroinvertebrate and fish population diversity and densities will be met
primarily through the bedform diversity improvements, in-stream structures, and the extensive
wetland areas.
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Areas adjacent to Project Area 14 consist primarily of old fallow fields of low ecological value,
as described in Section VI-Reach Level Assessment. Furthermore, there are no existing
wetlands within Project Area 14.
o. Project Area 15
The proposed design stream types in Project Area 15 are made up of a Rosgen C4 (UT6a) and a
Rosgen B4c (UT6a2). DesigningUT6a as a C4 is made possible by widening the valley floor to
create sufficient room for a meander pattern typical of C4 streams. Restoration will involve a
Rosgen Priority 2 approach to create a floodplain bench at the historic floodplain bench elevation
and increase floodplain connectivity. UT6a2, a tributary to UT6a, will maintain its existing
alignment while sharp bends are smoothed out to address sediment sources. The channel bed in
UT6a2 will be raised, following a Rosgen Priority 1 Restoration Approach. Channel dimensions
across both tributaries in this project area will also be designed to be slightly smaller than the
regional curve prediction in order to promote more frequent floodplain access. These two
approaches in each stream channel will promote more frequent floodplain access and meet Level
2 – Hydraulic design goals of increased floodplain connectivity.
Level 3 – Geomorphology design goals for increased bedform diversity are met through the
installation of in-stream rock and wood structures that promote development of associated scour
pools. The B4c stream (UT6a2) will require stream structures to be placed frequently to promote
the development of scour pools to help regulate energy dissipation in the steeper B4c type
stream. Also, the hardened in-stream structures will improve lateral stability to protect
infrastructure and provide grade control for vertical stability. This combined with wooden
structures, such as toe wood, along actively eroding banks will ensure that the design goals of
reducing sediment loads and providing habitat are met. In addition, the Service has recognized
that stability cannot be achieved without the proper riparian conditions. The Service has
proposed dense wetland riparian plantings that will extend beyond the limits of the design belt
width to increase the stability of the system.
Level 4 – Physicochemical design objectives of reducing nutrient loads will be met primarily
through the bank stabilization and the creation of extensive wetland areas. Level 5 – Biology
design objectives of increasing macroinvertebrate and fish population diversity and densities will
be met primarily through the bedform diversity improvements, in-stream structures, and the
extensive wetland areas.
Areas adjacent to Project Area 7 consist primarily of old fallow fields of low ecological value, as
described in Section VI-Reach Level Assessment. Therefore, the only potential adverse impacts,
other than the ones described above in Section VIII.E.3.b-Potential Adverse Impacts, are to 0.05
acres of existing, low ecological value wetland areas. The impacts to these existing wetlands will
be self-mitigating through the creation of new wetland areas that significantly exceed the
existing wetland area in acres and ecological value. Details of wetland creation are presented in
Section VII-Wetland Assessment. Exact figures and locations of wetland impacts are referenced
in Section IX-Impacts to Existing Resources and Appendix L.
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p. Project Area 16
Project Area 16 is comprised of four unnamed tributaries to the Piney Run mainstem that help
form an extensive wetland complex in the forested area. UT7, UT8 and UT8a are made up of
small grass channels that move across the Piney Run floodplain, while UT9 has a slightly higher
grade and confinement from the valley it sits in. The upstream portion of UT7 will have five
berms installed to establish a regenerative storm conveyance (RSC) system and help promote
sediment retention. Work on the downstream end of UT7 will then primarily focus on the
installation of log steps and constructed riffles to provide stability and in-stream habitat. The
UT8, UT8a, and UT9 tributaries will have limited work done on them except stabilization near
the confluence with the Piney Run mainstem.
To achieve the Level 3 – Geomorphology lateral stability and bedform diversity design goals, the
Service has planned for the limited installation of constructed riffles and log drops. Log drops
will promote the subsequent development of associated scour pools to increase bedform
diversity. The RSC in UT7 will help meet reduction and trapping of sediment design goals by
retaining water for longer periods of time. Overall, the Project Area will see minimal channel
work except for the installation of log drops and constructed riffles to help establish stable
environments around the confluences with the mainstem of Piney Run.
Areas adjacent to Project Area 16 consist primarily of forested wetland, as described in Section
VI-Reach Level Assessment. The establishment of the RSC and reconnection of the floodplain
to the stream will provide more frequent flood inundations of parts of these areas to provide
enhancement of wetland areas. Therefore, any impact to existing wetlands will be self-
mitigating through the enhancement of wetland areas that will improve the ecological value.
Details of wetland impacts and creation are presented in Section VII-Wetland Assessment.
3. In-stream Structures
Rock and log structures are in-stream structures, made of natural materials, used to divert erosive
stream flows away from stream banks and maintain streambed elevations. The most typical rock
and log structures used in stream restoration are cross-vanes, j-hooks, log-rollers and toe wood.
The rock and log structures provide streambed and bank stability and allow the streambed to
naturally armor and the riparian vegetation to establish.
The Service has determined that cross-vanes are only required at utility crossings to maintain
grade and the rest of the project area will utilize toe wood and wood j-hook structures to promote
stability and increase aquatic habitat. The locations of these structures were determined by
matching the naturally occurring pool-to-pool spacing and strategically placing them in areas that
would exhibit higher shear stress values during high flow events.
a. Cross Vane
The cross-vane (Figure 11) will establish grade control, reduce bank erosion, create a stable
width/depth ratio, and maintain channel capacity, while maintaining sediment transport capacity,
and sediment competence. The cross-vane also provides for the proper natural conditions of
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secondary circulation patterns commensurate with channel pattern, but with high velocity
gradients and boundary stress shifted from the near-bank region. The cross-vane is also a stream
habitat improvement structure due to: 1) an increase in bank cover as a result of a differential
raise of the water surface in the bank region; 2) the creation of holding and refuge cover during
both high and low flow periods in the deep pool; 3) the development of feeding lanes in the flow
separation zones (the interface between fast and slow water) due to the strong down welling and
upwelling forces in the center of the channel; and 4) the creation of spawning habitat in the tail-
out or glide portion of the pool (Rosgen, D.L., 2001). While the figure below shows a structure
consisting of large boulders, the cross-vane can be constructed using other materials such as logs
and rootwads.
Figure 11: Cross Vane in Plan View
b. J-Hook
The j-hook vane is an upstream directed, gently sloping structure composed of natural materials.
The structure can include a combination of boulders, logs and root wads, (Figure 12) and is
located on the outside of stream bends where strong down welling and upwelling currents, high
boundary stress, and high velocity gradients generate high stress in the near-bank region. The
structure is designed to reduce bank erosion by reducing near-bank slope, velocity, velocity
gradient, stream power, and shear stress. Redirection of the secondary cells from the near-bank
region does not cause erosion due to back-eddy re-circulation. The vane portion of the structure
occupies 1/3 of the bankfull width of the channel, while the hook occupies the center 1/3 as
shown in Figure 12 (Rosgen D.L., 2001).
Maximum velocity, shear stress, stream power, and velocity gradients are decreased in the near-
bank region and instead redirected towards the center of the channel. Sediment transport
competence and capacity can be maintained as a result of the increased shear stress and stream
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power in the center of the channel. Backwater is created only in the near-bank region, reducing
active bank erosion (Rosgen D. L., 2001). While the figure below shows a structure consisting of
large boulders, the j-hook vane can be constructed using other materials such as logs and root
wads.
Figure 12: J-Hook Vane in Plan View
c. Log Drop Structure
The log roller structure is an alternative to hardened riffles. These structures act as a grade
control, but instead of holding the grade of a glide feature, they instead hold the grade of the top
of riffle feature. The log roller consists of alternatively angled and sloped logs that are placed at
low grades in an effort to “roll” water back and forth while still concentrating energy towards the
center of the channel. The structure is typically used in straight portions of the channel as they
are effective in generating aeration and increased dissolved oxygen concentration by creating
hydraulic rises and falls while still directing stream energy towards the center of the channel.
These structures also add woody debris into the stream system promoting increased habitat for
aquatic species. Figure 13 shows a typical drawing for a log drop structure.
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Figure 13: Log Drop Structure
d. Toe Wood
The toe wood structure (Figure 14) incorporates native woody material into a submerged
undercut bank to replicate natural stream banks. Toe wood is positioned on the lower 1/3 to 1/2
of bankfull height to ensure it is submerged year round to prevent wood deterioration. Cuttings
with sod and live staking or woody transplants cover the toe wood and are installed up to the
bankfull stage. Not only does toe wood act as an area of increased roughness which promotes
reduction in shear stresses to the outside of the meander, it also serves as a haven for benthic
macroinvertebrates and fish communities.
Figure 14: Toe Wood
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e. Oxbow/Vernal Pool Features
Oxbow lakes (Figure 15) are formed when river erosion wears through the bank between two
consecutive bends. Most water travels through the new channel, and the old bend is cut out, with
water only passing through it very slowly. This slow speed causes sediment that is suspended in
the river water to settle on the old bend's riverbed. Eventually, enough sediment settles in the old
bend to close it off from the new channel and an oxbow lake is formed (DK Books, Lake
Formation).
The Service utilizes abandoned sections of the original stream alignment to create oxbow
features in the Piney Run design for a variety of reasons. The introduction of these discontinuous
oxbow pool features provides additional rearing habitat for fish species as well as excellent
refuge for other aquatic species. Beavers are also naturally drawn to these areas and they serve as
a preferred location for dens and dams. This prevents beavers from impacting or influencing
channel flow and minimizes the threat of beaver-related damming and ponding of the restored
stream reach.
Figure 15: Oxbow Creation
f. Rock/Log Deflector
The Rock/Log Deflector (Figure 16) is an upstream directed, gently sloping structure composed
of natural materials. The structure can include a combination of boulders, logs and root wads and
is located on the outside of stream bends. The structure is designed to reduce bank erosion by
reducing near-bank slope, velocity, velocity gradient, stream power and shear stress. The
structure occupies 1/3 of the bankfull width of the channel.
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Maximum velocity, shear stress, stream power and velocity gradients are decreased in the near-
bank region and increased in the center of the channel. Sediment transport competence and
capacity can be maintained as a result of the increased shear stress and stream power in the
center of the channel. Backwater is created only in the near-bank region, reducing active bank
erosion (Rosgen D. L., 2001).
Figure 16: Rock Deflector in Plan View
g. Constructed Riffle
Constructed Riffles (Figure 17) are installed to provide immediate grade control for the project
area using stone as a substrate. These structures remain stable while the pavement and sub-
pavement layers develop in the restored stream providing long term grade control. The stone in
the constructed riffle shall be placed in such a way as to mimic the action of a natural riffle by
producing turbulent flow.
Figure 17: Constructed Riffle in Plan View
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h. Rock Step
Rock Steps (Figure 18) are in-stream structures installed at the downstream end of a riffle to
provide grade control for the riffle while the pavement and sub-pavement layers develop
providing long term grade control. They consist of a row of foot and header rocks with filter
fabric placed on the upstream side of the structure. The elevation of the top footer rocks is equal
to the stream bed.
Figure 18: Rock Step in Plan View
i. Step Pool Channel
Step Pool Channels (Figure 19) provide grade control in areas of high slope or when a large
grade change is needed, but limited by stream length. They consist of a rock step constructed
with header and footer rocks for grade control. Pools are constructed between the steps with
smaller stones to provide energy dissipation. The pool to pool spacing gets smaller as the slope
increases.
Figure 19: Step Pool Channel in Plan View
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j. Stacked Rock Wall
Stacked Rock Walls (Figure 20) consist of large boulders with at least 2 parallel flat surfaces are
placed in rows along a bank to prevent bank erosion. Footer stones are buried below the invert
of the channel to protect from toe scour. Additional boulders are stacked on top to reached the
desired elevation. Rocks in the wall should be touching on the stream side to minimize voids
between the rocks. Filter fabric is placed behind the wall and the area is back filled with stone to
seal the voids between the boulders.
Figure 20: Stacked Rock Wall in Plan View
k. Grade Control Woody Riffle
Grade Control Woody Riffles (Figure 21) are a variation of a constructed riffle that primarily
uses logs and woody debris instead of rock as the substrate to provide grade control. The
upstream and downstream end are constructed with header and footer logs, while channel in
between is filled with layers of smaller logs and woody debris. During construction, the voids
between the woody debris are backfilled with sand and gravel.
Figure 21: Grade Control Woody Riffle in Plan View
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l. Ford Stream Crossing
Ford stream crossings (Figure 22) are used as an alternative to culverts or bridges on lightly
travelled roads. They limit the impact to the channel cross section and don’t constrict or reduce
channel capacity during high flow events. The crossing is installed at a right angle to stream
flow and is armored with stone to prevent the channel from being disturbed by vehicle traffic.
Figure 22: Ford Stream Crossing Structure
m. Rock Toe
A Rock Toe (Figure 23) consists of a line of large rocks along the toe of the stream bank
designed to prevent bank erosion. Approximately ½ of the rock is placed below the invert of the
stream to protect the bank from toe scour. After installation of the rock, a soil lift is constructed
on top of the line of rocks to the bankfull elevation and allows establishment of vegetation along
the bank.
Figure 23: Rock Toe Structure
n. Swale with Ditch Plugs
These structures consist of a series of cobble weirs with a consolidated clay base. The purpose
of the ditch plugs is to prevent erosion of the swales during runoff events. With the clay base,
runoff is retained in the pools upstream of the cobble weirs. This creates a pool on the upstream
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side of the structure; creating pool habitat, water storage and causing infiltration. The intent of
the structures is to provide both a water quantity and a water quality improvement through the
retention and infiltration of the runoff. A typical swale with ditch plugs is shown in Figure 24.
Figure 24: Swale with Ditch Plugs in Plan View
4. Hydrologic and Hydraulic Analyses
Evaluating the hydraulics of a stream system is an important component to any assessment
because it gives a better understanding of how water and sediment are transported through the
channel and its associated floodplain. Since one of the design approaches used for this project
was NCD, bankfull validation was required before conducting the hydraulic analysis. Detailed
results of the hydrology and hydraulic assessment can be found in Appendices K – Velocity
Calculations and L - HEC-RAS: Existing and Proposed.
a. Bankfull Verification
Bankfull discharge characterizes the range of discharges that is effective in shaping and
maintaining a stream. Over time, geomorphic processes adjust the stream capacity and shape to
accommodate the bankfull discharge within the stream. Bankfull discharge is strongly correlated
to many important stream morphological features (e.g., bankfull width, drainage area, etc.) and is
a critical piece of data used for several assessment parameters. Bankfull discharge is also used in
natural channel design procedures as a scale factor to convert morphological parameters from a
stable reach of one size to a disturbed reach of another size. The Service used Regional
Relationships as well as Resistance Relationships to determine the bankfull discharge and
channel dimension at the Big Cove Creek.
i. Geomorphic Indicators
During the Piney assessment, the Service identified bankfull stage using geomorphic indicators
formed by the stream as described by McCandless (2003). Figure 25 depicts significant
geomorphic indicators typically found in the Mid-Atlantic. Based on these indicators, the
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Service identified a consistent geomorphic feature at the Piney Run. This geomorphic indicator
was typically a significant slope break or back of bench found throughout the project area. A
stable riffle was located within the project and surveyed to calculate stable channel dimensions
(i.e., width, depth, and area) associated with this geomorphic indicator. The riffle cross section
dimensions were then compared to the regional curves in the Bankfull Discharge and Channel
Characteristics of Stream in the Piedmont Hydrologic Region (McCandless and Everett, 2002).
Details of this comparison are described below in Section VIII.F.4.a.iii-Resistance Relationships.
Figure 25: Typical Bankfull Indicators (McCandless, 2003)
ii. Regional Relationships
The regional curve estimates channel discharge based on a linear regression equation derived
from gaged sites across the same physiographic region with similar characteristics. Using only
the drainage area, the Service was able to derive the estimated channel width, depth, cross
sectional area and discharge using the Bankfull Discharge and Channel Characteristics in the
Piedmont Hydrologic Regions regional curve (McCandless and Everett, 2002) (Table 16). This
information was then compared to the field measured riffle cross section to validate bankfull
dimension and discharge.
iii. Resistance Relationships
There are several methods to estimate bankfull discharge and velocity using resistance
relationships. These methods typically make use of the cross sectional area, flow depth,
representative particle size of channel substrate, channel slope, and a determined roughness
coefficient, or “friction factor”. The Service used the Roughness Coefficient equation to
determine discharge. This equation, 𝒖 = 𝟏. 𝟒𝟗 ∗ 𝑹𝟐 𝟑⁄ ∗ 𝑺𝟏 𝟐⁄ /𝒏, uses the hydraulic radius of the
representative cross section, the channel slope, and a known Manning’s n (based on stream type)
to determine velocity and discharge values. This method closely matched the back calculated
roughness coefficient and was in agreement with the regional relationship findings and proved to
be an appropriate estimate for bankfull discharge for all Project Areas except for Project Area 7 –
Piney mainstem. Project Area 7 channel dimensions are significantly less than the region curve
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channel dimensions because of Piney Run Reservoir, located approximately 2 miles upstream of
the project area. Piney Run Reservoir significantly affects the flow regime for Project Area 7
and as well as Project Area 8, which is downstream of Project Area 7. A discharge analysis,
using HEC-HMS, determined that the hydrograph influencing Project Areas 7 and 8 is primarily
influenced by the drainage area downstream of the reservoir versus the entire watershed drainage
area. This is because maximum flow releases from Piney Reservoir do not exceed flows greater
than a 1 year storm event. Therefore, Project Areas 7 and 8 have flow discharges and channel
dimension characteristics associated with the drainage area downstream of the reservoir, which is
4.6 square miles versus the 15.2 square miles associated with the entire watershed. This
constraint will significantly influence design channel dimensions, specifically a smaller channel
then what would be expected for a project drainage area of 15.2 square miles. In fact, the
regional curve bankfull channel dimensions associated with a 4.6 square miles are: Area – 53
square feet, Width – 27 feet, Depth – 2.0 feet and Discharge – 270 cubic feet per second. These
channel dimensions compare well to the reference riffle channel dimensions, further supporting
the significant influence of Piney Run Reservoir.
The design channel dimensions for Project Areas 5 and 6 are slightly less than the reference riffle
and regional curve channel dimensions. The Service intentionally set smaller design channel
dimensions in order to inundate the floodplain more frequently. Given that the upstream
sediment supply is low and that the design channel dimensions are not smaller than the reference
riffle dimensions, the proposed channel dimension should be self-sustaining over time.
A summary of bankfull discharges and velocities can be found in Table 16 and detailed
information can be found on the “Proposed Design Conditions Plan Set Computations of
Velocity and Bankfull Discharge Using Various Methods” worksheet in Appendix I – Velocity
Calculations.
Design and Regional Curve Bankfull Characteristics –
Project Area 3: DA= 1.23 mi2
Bankfull
Characteristics
Reference Cross
Section
Design Cross
Section
Regional
Curve (2005)
USGS
StreamStats
1.25 / 1.5 RI
Area (sq. ft) 25 20.5 21.1 -
Width (ft) 18 17.0 16.4 -
Depth (ft) 1.4 1.3 1.3 -
Velocity (ft/s) 3.78 - 3.92 3.1 4.9 -
Discharge (cfs) 95 - 99 62 103.0 102 / 138
Characteristics in the Piedmont Hydrologic regional curves (McCandless and Everett 2002)
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Design and Regional Curve Bankfull Characteristics –
Project Area 4: DA= 1.38 mi2
Bankfull
Characteristics
Reference Cross
Section
Design Cross
Section
Regional
Curve (2005)
USGS
StreamStats
1.25 / 1.5 RI
Area (sq. ft) 25 22.0 22.0 -
Width (ft) 18 17.0 16.8 -
Depth (ft) 1.4 1.4 1.3 -
Velocity (ft/s) 3.78 - 3.92 3.6 4.9 -
Discharge (cfs) 95 - 99 99 108.0 110 / 148
Characteristics in the Piedmont Hydrologic regional curves (McCandless and Everett 2002)
Design and Regional Curve Bankfull Characteristics –
Project Area 5: DA= 2.24 mi2
Bankfull
Characteristics
Reference Cross
Section
Design Cross
Section
Regional
Curve (2005)
USGS
StreamStats
1.25 / 1.5 RI
Area (sq. ft) 32 25.0 31.0 -
Width (ft) 15 19.3 20.1 -
Depth (ft) 2.1 1.3 1.54 -
Velocity (ft/s) 5.28 – 5.36 3.2 5.0 -
Discharge (cfs) 166 - 170 99 154.0 170 / 226
Characteristics in the Piedmont Hydrologic regional curves (McCandless and Everett 2002)
Design and Regional Curve Bankfull Characteristics –
Project Area 6: DA= 2.24 mi2
Bankfull
Characteristics
Reference Cross
Section
Design Cross
Section
Regional
Curve (2005)
USGS
StreamStats
1.25 / 1.5 RI
Area (sq. ft) 32 25.0 31.4 -
Width (ft) 15 19.3 20.2 -
Depth (ft) 2.1 1.3 1.6 -
Velocity (ft/s) 5.28 – 5.36 2.8 5.0 -
Discharge (cfs) 166 - 170 166 156.1 173 / 229
Characteristics in the Piedmont Hydrologic regional curves (McCandless and Everett 2002)
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Design and Regional Curve Bankfull Characteristics –
Project Area 7: DA= 15.2 mi2
Bankfull
Characteristics
Reference Cross
Section
Design Cross
Section
Regional
Curve (2005)
USGS
StreamStats
1.25 / 1.5 RI
Area (sq. ft) 52 45.0 125.2 -
Width (ft) 35 25.8 42.4 -
Depth (ft) 1.5 1.8 3.0 -
Velocity (ft/s) 3.30 - 3.50 2.5 5.3 -
Discharge (cfs) 177 - 182 176 658.9 635 / 835
Characteristics in the Piedmont Hydrologic regional curves (McCandless and Everett 2002)
Design and Regional Curve Bankfull Characteristics –
Project Area 9: DA= 0.24 mi2
Bankfull
Characteristics
Reference Cross
Section
Design Cross
Section
Regional
Curve (2005)
USGS
StreamStats
1.25 / 1.5 RI
Area (sq. ft) - 6.0 4.4 -
Width (ft) - 8.5 7.1 -
Depth (ft) - 0.7 0.6 -
Velocity (ft/s) - 2.9 4.6 -
Discharge (cfs) - 9 20.0 17.2 / 24.5
Characteristics in the Piedmont Hydrologic regional curves (McCandless and Everett 2002)
Design and Regional Curve Bankfull Characteristics –
Project Area 14: DA= 0.58 mi2
Bankfull
Characteristics
Reference Cross
Section
Design Cross
Section
Regional
Curve (2005)
USGS
StreamStats
1.25 / 1.5 RI
Area (sq. ft) 11 12.0 9.1 -
Width (ft) 10 12.0 10.4 -
Depth (ft) 1.1 1.0 0.9 -
Velocity (ft/s) 3.41 - 3.71 3.5 4.7 -
Discharge (cfs) 37 - 40 37 42.9 55.2 / 73.2
Characteristics in the Piedmont Hydrologic regional curves (McCandless and Everett 2002)
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Design and Regional Curve Bankfull Characteristics –
Project Area 15: DA= 0.76 mi2
Bankfull
Characteristics
Reference Cross
Section
Design Cross
Section
Regional
Curve (2005)
USGS
StreamStats
1.25 / 1.5 RI
Area (sq. ft) 11 12.0 14.1 -
Width (ft) 10 12.0 13.2 -
Depth (ft) 1.1 1.0 1.1 -
Velocity (ft/s) 3.41 - 3.71 3.2 4.8 -
Discharge (cfs) 37 - 40 37 68.0 89 / 117
Characteristics in the Piedmont Hydrologic regional curves (McCandless and Everett 2002)
Table 16: Design and Regional Curve Bankfull Characteristics
iv. Bankfull Validation
The bankfull discharges range between 9 to 176 cubic feet per second (cfs) since there are
numerous project areas with differing drainage areas. However, the discharges generally
correspond well with the regional curve, with exception of Project Area 7 – Piney Run because
of the flow restrictions associated with Piney Reservoir, which was discussed in Section
VIII.F.2.g-Project Area 7. More important is how closely the surveyed cross section channel
dimensions correspond with the regional curve. Estimating discharge has a higher range of error
due to the sensitivity of the factors used in calculating discharge. Measurement of cross section
area is more precise and a better indicator for validating bankfull flow. However, it should be
noted that most of the proposed design cross dimensions are slightly less than the regional curve
data. This was intentional by the design team to better meet the frequent floodplain inundation
design objective. By designing a channel slightly smaller than the regional curve dimensions,
the floodplain can be accessed more frequently by flood flows. Furthermore, channel aggradation
should not be a problem since the sediment supplies are mostly low and the proposed design
channel dimensions can transport what is being delivered, which is described below in Sections
VIII.F.4.c-Sediment Analysis.
b. Hydrologic and Hydraulic Assessment
The Service used the HEC-RAS model to test stream channel and floodplain stability of the
proposed design. HEC-RAS model runs were completed for only those project areas that
involved significant channel modifications: Project Areas 3, 4, 5, 6, 7, 9, 14, and 15. All other
project areas only had minimal and localized restoration activities that would not significantly
alter stream hydrology and hydraulics. Detailed results of the hydraulic assessment can be found
in Appendix J - HEC-RAS: Existing and Proposed.
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The HEC-RAS model was run using bankfull discharges and flood discharges for each as shown
above in Table 16: Design and Regional Curve Bankfull Characteristics. These flows were
derived from the resistance relationship using existing and design channel and valley geometry.
A Manning’s roughness coefficient of 0.029 to 0.036 was used for in-channel roughness, which
is common among low to moderate gradient streams and an overbank roughness of 0.045 was
used as a worst-case scenario, lightly vegetated roughness. The HEC-RAS model run showed
that proposed flows would have channel velocities at bankfull stage ranging between 1.52 and
5.67 ft/s with the majority of them around 2.5 to 4.5 ft/s and shear stresses ranging between 0.13
and 2.30 ft/s with the majority of them around 0.25 to 1.70 ft/s (Table 17). The proposed shear
stresses and velocities are typical of a project this size and less than all the existing stream
energy conditions except for Project Area 5. Project Area 5 has a maximum proposed velocity
of 5.67 ft/s and is not considered to be high enough to result in stream degradation. Additionally,
lateral and vertical control structures are used throughout this reach to further reduce risk of any
degradation.
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Piney Run- HEC-RAS Model Results
Bankfull
Characteristics
Storm
Event
Existing
Conditions
Channel Shear
Stress (lbs/ft2)
Design
Conditions
Channel Shear
Stress (lbs/ft2)
Existing
Conditions
Channel
Velocity (ft/s)
Design
Conditions
Channel
Velocity (ft/s)
Existing
Conditions
Water Elevation
(ft)
Proposed
Conditions
Water Elevation
(ft)
Project Reach
3
Bankfull 0.32 - 2.02 0.23 - 1.88 2.25 - 5.12 1.89- 4.96 450.15-458.74 451.32-459.30
2 year 0.45 - 1.72 0.35 - 1.52 2.75 - 4.97 2.43 - 4.92 450.95-459.46 451.88-460.03
10 year 0.85 - 2.27 0.61 - 2.21 4.12 - 6.71 3.40 - 6.42 452.39-460.90 452.73-461.08
50 year 0.96 - 2.68 1.19 - 2.82 4.63 - 7.69 4.97 - 7.61 453.58-461.82 453.61-461.95
100 year 1.29 - 2.90 1.41 - 2.88 5.43 - 8.12 5.51 - 7.80 454.08-462.21 454.04-462.35
Project Reach
4
Bankfull 0.31 - 2.53 0.52 - 1.65 2.31 – 6.00 2.80 - 4.78 434.95-448.80 434.34-450.86
2 year 0.54 - 2.76 0.57 - 2.86 3.20 - 6.67 3.07 - 6.93 435.60-449.65 434.96-451.31
10 year 0.48 - 3.32 0.91 - 2.68 3.32 - 8.52 4.16 - 7.45 436.69-451.09 435.93-452.17
50 year 1.10 - 3.96 1.24 - 5.83 5.16 - 9.65 5.17 - 11.28 438.01-452.48 437.05-452.98
100 year 1.26 - 4.70 1.38 - 4.45 5.58 - 10.63 5.53 - 10.18 438.55-452.94 437.62-453.38
Project Reach
5
Bankfull 0.18 - 0.92 0.40 - 2.30 1.84 - 3.44 1.83 - 5.67 428.46-433.48 426.92-433.00
2 year 0.33 - 1.55 0.45 - 2.18 2.59 - 4.65 2.05 - 5.90 429.21-434.27 427.64-433.54
10 year 0.48 - 2.31 0.55 - 3.17 3.37 - 6.3 2.90 - 7.77 430.89-435.64 428.76-434.57
50 year 0.40 - 3.53 0.69 - 2.09 3.18 - 8.57 3.59 - 6.83 432.97-437.09 431.10-435.72
100 year 0.32 - 3.91 0.54 - 2.38 2.91 - 9.23 3.58 - 7.43 434.21-437.67 432.48-436.26
Project Reach
6
Bankfull 0.25 - 1.44 0.13 - 1.51 2.16 - 5.23 1.52 - 4.96 419.92-427.10 418.60-426.26
2 year 0.19 - 2.30 0.09 - 1.74 1.94 - 6.71 1.24 - 5.33 420.72-427.79 418.89-426.83
10 year 0.34 - 2.52 0.31 - 2.82 2.70 - 7.23 2.39 - 6.97 421.72-429.14 419.61-427.77
50 year 0.46 - 2.74 0.47 - 4.24 3.20 - 7.93 3.13 - 8.83 422.39-430.00 420.42-428.54
100 year 0.52 - 2.91 0.51 - 3.63 3.46 - 8.25 3.48 - 8.39 422.67-430.35 420.82-429.07
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Bankfull
Characteristics
Storm
Event
Existing
Conditions
Channel Shear
Stress (lbs/ft2)
Design
Conditions
Channel Shear
Stress (lbs/ft2)
Existing
Conditions
Channel
Velocity (ft/s)
Design
Conditions
Channel
Velocity (ft/s)
Existing
Conditions
Water Elevation
(ft)
Proposed
Conditions
Water Elevation
(ft)
Project Reach
7
Bankfull 0.09 - 2.35 0.09 - 1.14 1.36 - 6.11 1.36 - 4.28 413.06-420.05 413.06-419.9
2 year 0.22 - 2.73 0.11 - 1.78 2.29 - 7.56 1.61 - 5.92 416.63-422.19 416.61-421.51
10 year 0.30 - 1.40 0.19 - 1.55 2.83 - 5.93 2.27 - 6.08 419.01-423.72 418.98-422.80
50 year 0.41 - 1.69 0.26 - 1.51 3.49 - 6.70 2.78 - 6.29 421.42-425.11 421.40-424.14
100 year 0.36 - 1.47 0.26 - 1.27 3.33 - 6.4 2.85 - 5.91 422.9-425.76 422.89-424.97
Project Reach
9
Bankfull 0.25 - 1.33 0.48 - 1.32 1.56 - 3.76 2.33 - 3.72 522.14-538.36 522.72-539.88
2 year 0.31 - 1.71 0.63 - 1.69 1.85 - 4.46 2.78 - 4.46 522.33-538.56 523.01-540.10
10 year 0.61 - 2.45 1.20 - 2.76 2.97 - 5.92 4.27 - 6.43 522.85-539.15 523.62-540.68
50 year 1.08 - 2.85 1.86 - 3.06 4.19 - 7.00 5.73 - 7.27 523.53-539.81 524.40-541.25
100 year 1.37 - 3.15 2.20 - 3.68 4.84 - 7.58 6.43 - 8.17 523.85-540.10 524.80-541.56
Project Reach
14
Bankfull 0.38 - 2.94 0.53 - 1.93 1.50 - 4.13 2.54 - 4.95 456.13-465.95 456.14-465.64
2 year 0.76 - 3.06 0.90 - 2.14 2.42 - 4.95 3.98 - 5.96 457.76-467.13 457.12-466.84
10 year 1.04 - 4.02 1.10 - 4.20 3.07 - 6.15 4.78 - 8.91 458.95-468.40 458.23-468.16
50 year 1.51 - 5.74 1.42 - 4.46 3.86 - 7.70 5.74 - 9.80 459.72-469.74 459.25-469.52
100 year 1.81 - 6.97 1.76 - 4.54 4.30 - 8.65 6.50 - 10.11 460.03-470.29 459.64-469.97
Project Reach
15
Bankfull 0.21 - 4.83 0.27 - 1.79 1.79 - 5.27 1.91 - 4.69 434.72-453.25 435.36-453.18
2 year 0.58 - 3.17 0.47 - 2.25 3.29 - 7.11 2.79 - 6.02 436.01-454.88 436.02-454.12
10 year 1.30 - 7.12 0.92 - 4.07 5.28 - 8.33 4.11 - 8.82 437.01-455.83 436.66-455.17
50 year 1.44 - 5.17 1.40 - 5.73 5.79 - 9.91 5.24 - 11.15 437.87-457.42 437.38-456.35
100 year 1.53 - 5.90 1.56 - 4.98 6.03 - 10.86 5.64 - 9.98 438.35-457.70 437.73-457.64
Table 17: HEC-RAS Model Results
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c. Sediment Analysis
The objective of sediment transportation for the project is to design Piney Run and its tributaries
to maintain the competency to entrain the largest measured particle size of the bar sample
determined by the sieve analysis conducted by the Service. As noted previously, a sediment
analysis was done at individual project areas representing larger reaches that would undergo
restoration that would modify plan, profile and dimension. Those areas that were not being
reconfigured were not analyzed due to the fact that competency was not perceived to be an issue.
Initial competency findings showed that Piney Run did not have the required depth to initiate
movement of the largest measured particle size (49mm) of the bar sample. This is further
supported by field observed deposition patterns which included some mid-channel bar formation
as well as lateral bars. While these deposition formations are isolated, they do indicate a
reduction in sediment competency related to a shallowing condition that is a result of channel
widening. The Service aims to reduce channel width, cross sectional area, and increase mean
depth to increase the channel’s sediment transport competency. The increased depth meets the
required depth as shown by Rosgen’s power trend line on Shields critical shear stress
relationship. The predicted particle size that can be moved is 64 mm which is just slightly larger
than the largest particle size (49 mm) collected in the bar sample, but smaller than the riffle
d100. This ensures the channel will not degrade over time.
Competency findings showed that the lower portion of UT6 was competent and able to initiate
movement of the largest particle size found of the bar sample. This is further supported by no
major observed deposition patterns which would indicate excessive aggradation. The Service
will maintain similar geometric configuration of the channel, stabilize lateral erosion issues, and
also allow the channel to access its floodplain once more. Additionally, since stream length is
being reduced, slope will increase slightly. The design depth meets the required depth as shown
by Rosgen’s power trend line on Shields critical shear stress relationship. The predicted particle
size that can be moved is 64 mm which is just slightly larger than the largest particle size (50
mm) collected in the bar sample, but smaller than the riffle d100. This ensures the channel will
not degrade over time.
Similar to Piney Run, competency findings for the lower portion of UT6 showed that there was
not quite enough depth to initiate movement of the largest measured particle size of the bar
sample. In this area, the Service aims to reduce the channels cross sectional area as much as
possible while still maintaining a competent configuration. The channel dimensions will meet the
required dimensions as shown by Rosgen’s power trend line on Shields critical shear stress
relationship. The predicted particle size that can be moved is 73mm which is just slightly smaller
than the largest particle size (90 mm) collected in the bar sample, this ensures the channel will
not degrade over time.
Competency findings showed that the lower portion of UT6a were competent and able to initiate
movement of the largest particle size found on the point bar. This is further supported by no
major observed deposition patterns which would indicate excessive aggradation. The Service
will maintain similar geometric configuration of the channel, stabilize lateral erosion issues, and
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also allow the channel to access its floodplain once more. The design depth meets the required
depth as shown by Rosgen’s power trend line on Shields critical shear stress relationship. The
predicted particle size that can be moved is 95 mm which is just slightly larger than the largest
particle size (84 mm) collected in the bar sample, but smaller than the riffle d100. This ensures
the channel will not degrade over time.
The main stability problems within Piney Run and its tributaries are mostly related to lateral
instability problem (e.g., widespread bank erosion). A sediment capacity analysis was not
conducted since Piney Run and its tributaries do not appear to have a significant aggradation or
degradation stability problem. Table 18 summarizes the Service’s findings and detailed
information can be found in Appendix C.
Sediment Transport Competency
Representative
Reach Parameter
Measurement
Method
Restoration Condition
Design Required
Piney Main
Sediment
Transport
Competency
Required Depth 1.80 1.70
Required Slope 0.004 0.004
UT6 Middle
Sediment
Transport
Competency
Required Depth 1.2 1.12
Required Slope 0.008 0.004
UT6 Lower
Sediment
Transport
Competency
Required Depth 1.3 1.36
Required Slope 0.01 0.01
UT6a
Sediment
Transport
Competency
Required Depth 1.0 0.99
Required Slope 0.01 0.01
Table 18: Sediment Transport Capacity for Representative Reaches
5. Vegetation Design
The riparian buffer is an integral part of the stream ecosystem, providing bank stability and
nutrient uptake, serving as a food source for aquatic organisms downstream of the project area,
and providing terrestrial habitat and migration corridors for wildlife. Many species of wildlife
will benefit including migratory birds, amphibians, reptiles, small mammals, and pollinating
insects. Shading from the buffer will moderate stream temperature and prevent excessive algal
growth. The riparian vegetation will help increase infiltration and evapotranspiration, which will
benefit stream base flow in lower stream sections and help reduce erosive velocities of runoff.
Large woody debris derived from the buffer is an important component of aquatic habitat.
The riparian planting has five distinct zones; stream banks, riparian vegetation, forested
wetlands, emergent wetlands and uplands. Zone 1 – Streambank planting will include installation
of live stakes along all disturbed stream banks to help provide early stabilization of banks with
vegetation establishment. Next, Zone 2 – Riparian Planting will include a combination of trees
and shrubs along either bank where restoration work takes place. The riparian planting zone will
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extend into the excavated floodplain from the top of bank and will not follow the sinuosity of the
stream channel. This will help ensure vegetation is established across the full floodplain width to
help provide stability during large flood flows. Zone 3 – Forested Wetlands will include a
mixture of trees and shrubs specific for forested wetland development. Areas that will be
developed for forested wetland include where the existing channel will be abandoned during
channel realignment in several project areas and the subsequent creation of oxbow pools. There
is also extensive establishment of forested wetlands in the floodplain of Project Area 3. Zone 4 –
Emergent Wetlands will use a combination of shrubs to establish vegetation. Emergent uplands
will be established in Project Area 6 and near the confluence of UT6 with Piney Run in Project
Area 7. Zone 5 – Upland planting will take place as a further buffer beyond the Zone 2 –
Riparian Planting. It will extend, where practical, to the toe of slope along the floodplain of the
project areas where significant channel work is done.
Overall planting densities of trees and shrubs combined across all zones will be 303 stems per
acre (12’ x 12’ spacing. Live stakes in Zone 1 will be placed as a single row with three-foot
spacing. Seed mix will be applied to Zones 1 – 4 at a rate of 20 lbs/acre and Zone 5 will have
permanent seed mix applied at a rate of 10 lbs/acre. Temporary seed mix will be applied to all
disturbed areas as construction progresses. The detailed planting plan can be found in Appendix
K.
IX. IMPACTS TO EXISTING RESOURCES
There are a variety of ecologically valuable resources throughout the project areas that the
Service took great care in observing, avoiding, and maintaining during the design phase.
However, in some cases impacts to these sensitive areas were unavoidable and necessary for the
success of the overall project.
Piney Run, UT6, and UT6e stream lengths were reduced / impacted in order to achieve a more
stable configuration. Since the restoration configuration resulted in reduced stream length, the
impacts to resources had to reflect the reduction. However, while the net change is negative, the
stability, habitat value, and overall function of the stream will improve.
Wetlands found adjacent to the stream channels were also impacted in various ways, both
permanently and temporarily. Permanent impacts came as a result of channel realignment, where
the old channel was abandoned for a more desirable configuration. In which case, the new
configuration may meander into an existing wetland buffer or wetland. Typically, these impacts
are mitigated almost instantly, since the abandoned channel is designed to be converted into a
similar type wetland resulting in a net change of zero. Temporary impacts include those areas
where the resource would be reverted back to its original condition post impact. These areas
were generated as a result of temporary construction haul roads and crossings necessary to
implement the restoration project. Collectively, with the restoration also creating additional
wetland features, the project shows a substantial net gain.
Temporary and permanent impacts to perennial open water (POW) stream areas as well as
palustrine emergent wetlands (PEM) were identified and tabulated and are shown in detail in
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Table 19 below. Additionally, impact figures and net change information can be seen in
APPENDIX L.
Aquatic Resource Name
1
Existing Resource
Class Activity
Impact Duration
Impact Area
(square ft)
Impact Length
(linear ft)
Proposed resource class
post-construction
Piney Run Per Realignment / Fill Permanent 21,982 852 Floodplain
UT6 Per Realignment / Fill Permanent 8,082 449 Floodplain
UT6a1 Per Realignment / Fill Permanent 476 69 Floodplain
UT6e Per Realignment / Fill Permanent 467 55 Floodplain
Wet 01 Buffer PEM Stream Channel Permanent 88 N/A Open Water
Wet 02 PEM Stream Channel Permanent 1207 N/A Open Water
Wet 02 PEM Haul Road Temporary 3301 N/A PEM
Wet 02 PEM Floodplain Grading Temporary 8391 N/A PEM
Wet 02 Buffer PEM Stream Channel Permanent 6770 N/A Open Water
Wet 02 Buffer PEM Haul Road Temporary 372 N/A PEM
Wet 02 Buffer PEM Floodplain Grading Temporary 11043 N/A PEM
Wet 03 PEM Stream Channel Permanent 342 N/A Open Water
Wet 03 PEM Floodplain Grading Temporary 3729 N/A PEM
Wet 03 Buffer PEM Stream Channel Permanent 860 N/A Open Water
Wet 03 Buffer PEM Haul Road Temporary 1310 N/A PEM
Wet 03 Buffer PEM Floodplain Grading Temporary 6187 N/A PEM
Wet 04 PEM Stream Channel Permanent 57 N/A Open Water
Wet 04 PEM Floodplain Grading Temporary 1305 N/A PEM
Wet 05 PEM Floodplain Grading Temporary 592 N/A PEM
Wet 05 Buffer PEM Stream Channel Permanent 1746 N/A Open Water
Wet 05 Buffer PEM Haul Road Temporary 308 N/A PEM
Wet 05 Buffer PEM Floodplain Grading Temporary 8103 N/A PEM
Wet 06 PEM Stream Channel Permanent 5 N/A Open Water
Wet 06 Buffer PEM Stream Channel Permanent 2107 N/A Open Water
Wet 06 Buffer PEM Haul Road Temporary 38 N/A PEM
Wet 07 PEM Stream Channel Permanent 623 N/A Open Water
Wet 07 PEM Floodplain Grading Temporary 2977 N/A PEM
Wet 07 Buffer PEM Stream Channel Permanent 1845 N/A Open Water
Wet 07 Buffer PEM Floodplain Grading Temporary 6262 N/A PEM
Wet 08 PEM Stream Channel Permanent 16 N/A Open Water
Wet 08 PEM Haul Road Temporary 12508 N/A PEM
Wet 08 Buffer PEM Stream Channel Permanent 379 N/A Open Water
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Aquatic Resource Name1
Existing Resource
Class Activity
Impact Duration
Impact Area
(square ft)
Impact Length
(linear ft)
Proposed resource class
post-construction
Wet 08 Buffer PEM Stream Channel Permanent 3912 N/A Open Water
Wet 08 Buffer PEM Haul Road Temporary 5257 N/A PEM
Wet 08 Buffer PEM Floodplain Grading Temporary 1946 N/A PEM
Wet 08 Buffer PEM Floodplain Grading Temporary 14837 N/A PEM
Wet 09 PEM Stream Channel Permanent 1978 N/A Open Water
Wet 09 PEM Floodplain Grading Temporary 8005 N/A PEM
Wet 10 PEM Stream Channel Permanent 4331 N/A Open Water
Wet 10 PEM Floodplain Grading Temporary 11517 N/A PEM
Wet 11 PEM Stream Channel Permanent 2739 N/A Open Water
Wet 11 PEM Floodplain Grading Temporary 1555 N/A PEM
Wet 11 Buffer PEM Stream Channel Permanent 2995 N/A Open Water
Wet 11 Buffer PEM Floodplain Grading Temporary 13796 N/A PEM
Total Temporary and Permanent Impacts 186,346 1425
Table 19: Table of Potential Impacts to Existing Resources
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LITERATURE CITED
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Conveyance (SPSC) Design Guidelines, Revision 4. Department of Public Works, Anne
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Function-Based Framework for Stream Assessment and Restoration Projects. U.S.
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13. McCandless, T. (2003). Maryland stream survey: Bankfull discharge and channel
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No. IWR-96-R-8
Piney Run Stream Restoration: Project Summary and Design Report
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APPENDIX A Assessment and Design Review Checklists
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APPENDIX B Watershed Assessment
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APPENDIX C Level 3 Assessment Representative Reaches Data
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APPENDIX D DNR MBSS Biology Report
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APPENDIX E Wetland Assessment
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APPENDIX F Soil Trench Data
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APPENDIX G Project Reach Specific Design Criteria
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APPENDIX H Implementation Costs
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APPENDIX I Velocity Calculations
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APPENDIX J HEC-RAS: Existing and Proposed
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APPENDIX K Planting Plan
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APPENDIX L Impacts to Existing Resources