Marshall Woods Restoration Project

Hydrology Specialist’s Report

Dustin Walters Hydrologist

October 1, 2014

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Table of Contents Proposed Actions and Related Activities ........................................................................ 4 Summary of Hydrologic Findings .................................................................................. 4 Analysis Framework: Forest Plan Direction, Guidance, and Regulatory Framework ... 4

Federal Regulations .................................................................................................... 4 State Regulations ........................................................................................................ 6 Lolo National Forest Plan ........................................................................................... 8

Analysis Data Sources and Methods ......................................................................... 11 Roads and Road Density Methods ............................................................................ 11 Road Encroachment .................................................................................................. 12 Sediment Delivery Modeling .................................................................................... 13 Water Yield Modeling .............................................................................................. 13

Affected Environment ................................................................................................ 14 Analysis Area and Landownership ........................................................................... 14 Climate and Hydrology ............................................................................................. 16 Wetlands ................................................................................................................... 16 Stream Channels ....................................................................................................... 16 Water Quality ............................................................................................................ 18 Source Water ............................................................................................................. 19 Roads......................................................................................................................... 19 Watershed Improvement History .............................................................................. 21

Water Resource Issues ................................................................................................ 21 Assessment Indicators ................................................................................................ 22 Desired Water Resource Condition ........................................................................... 24 Environmental Consequences .................................................................................... 25

No Action Alternative – Direct, Indirect, and Cumulative Effects ........................... 25 Action Alternatives Comparison – Alternatives B, C, and D ................................... 26 Cumulative Effects.................................................................................................... 34 Summary ................................................................................................................... 36

Consistency with Forest Plan and other Regulations .................................................... 37 References ..................................................................................................................... 39 Appendix A - BMP Effectiveness and Performance Criteria ....................................... 43

Effectiveness /reduction in erosion ................................................................................... 45 Measure ............................................................................................................................. 45

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Effectiveness ..................................................................................................................... 45

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This document summarizes issues and effects to the water resources from the proposed activities in the Marshall Woods project area.

Proposed Actions and Related Activities The Marshall Woods Restoration Project is designed to meet the goals of improvements to forest stand health, wildlife habitat, and watershed health; fuels reduction; and enhancements to recreational and educational opportunities. The three action alternatives propose various levels of thinning, prescribed burning, weed treatments, and changes to the road and trail system. Watershed improvement activities include weed treatments on haul routes, decommissioned roads, landings, and other areas with ground disturbance. Additional activities such as road storage, decommissioning, and road stream-road crossing upgrades are proposed under all action alternatives. Proposed resource protection measures and effectiveness are discussed in the effects analysis and also within Appendix A of this report.

Summary of Hydrologic Findings All action alternatives would lead to improvements over existing conditions for water resources. Proposed road BMP upgrades, storage, and decommissioning would align with INFISH Riparian Goals and Management Objectives.

There is anticipated to be a short-term increase in sediment from road-related project activities. Best Management Practices associated with haul routes would improve conditions and reduce sediment delivery on those roads post-timber sale.

All alternatives include design criteria and site-specific resource protection measures to eliminate or minimize effects to water resources. Proposed road, timber harvest, and fuel treatment activities are not expected to have detrimental effects on water resources in the analysis area.

Analysis Framework: Forest Plan Direction, Guidance, and Regulatory Framework The Lolo National Forest Plan (USDA 1986) provides Forest-wide management direction regarding water and hydrologic resources. Other direction is provided by federal and state laws, guidelines, executive orders, and other agency direction described below.

Federal Regulations A. The Federal Water Pollution Control Act of 1972 (Public Law 92-500) as amended in 1977 (Public Law 95-217) and 1987 (Public Law 100-4). Also known as the Federal Clean Water Act. The Lolo NF upholds the Federal Clean Water Act through the application and enactment of appropriate federal and state water quality protection permits (see below); the application of BMPs and monitoring for effectiveness; and by participating with the State

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of Montana in BMP forestry audits, water quality data collection, and implementation of Total Maximum Daily Loads (TMDLs) and Water Quality Restoration Plans (WQRPs). The Federal Clean Water Act governs forest management practices that have the potential to affect water quality. As stated in Section 101, the objective of the Act is “…to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” Control of point and non-point sources of pollution are among the means to achieve the stated objective. The U.S. Environmental Protection Agency (EPA) is charged with administration of the Act with the provision for delegating many permitting, administrative, and enforcement functions to State governments. In Montana, the designated agency is the Montana Department of Environmental Quality (MDEQ). Section 305(b) requires states to assess the condition of their waters and produce a biennial report summarizing the findings. Water bodies with impaired water quality (not fully meeting water quality standards) or threatened (likely to violate standards in the near future) are compiled by MDEQ in a separate list under Section 303(d) of the Act. This list must be submitted to EPA every two years. Water bodies on the 303(d) list (known as Water Quality Limited, WQL, waters) are to be targeted and scheduled for development of water quality improvement strategies on a priority basis. These strategies are in the form of Total Maximum Daily Loads, or TMDLs, when a pollutant is involved, and technically consist of the quantity of pollutants that may be delivered to a water body without violating water quality standards. A TMDL is the total amount of pollutant that a water body may receive from all sources without exceeding water quality standards. TMDL can also be defined as a reduction in pollutant loading that results in meeting water quality standards.

When water quality impairment is not related to a pollutant (e.g., habitat alteration) strategies are in the form of a Water Quality Restoration Plan (WQRP). Frequently, impairments are related to both pollutants and non-pollutants and TMDLs and WQRP are developed in concert. In practice TMDLs and WQRP alone or in combination are plans to improve water quality in a listed water body until water quality standards are met (i.e., until designated uses are fully supported).

Section 404 of the Act outlines the permitting process for discharging dredged or fill material into waters of the United States, including wetlands. The U.S. Army Corps of Engineers administers the 404 program. Under Section 401 of the Act, states and tribes may review and approve, set conditions on, or deny Federal permits (such as 404 permits) that may result in a discharge to State or Tribal waters, including wetlands. Applications for Section 404 permits are often joint 404/401 permits to ensure compliance at both the State and federal levels. Federal agency compliance with water pollution control mandates are addressed through Section 313 of the Clean Water Act and in Executive Order 12580 of January 23, 1987. Agency compliance is to be consistent with requirements that apply to “any nongovernmental entity” or private person. Compliance is to be in line with “…all Federal, State, interstate, and local requirements, administrative authority, and process and sanctions respecting the control and abatement of water pollution.” To comply with State Water Quality Standards, the Forest Service is required to apply water quality

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practices in State Forest Practices Regulations where applicable - reasonable land, soil, and water conservation practices, or specialized Best Management Practices. All these types of practices are designed with consideration of geology, land type, soil type, erosion hazard, climate, cumulative effects, and other factors in order to fully protect and maintain soil, water, and water-related beneficial uses, and to prevent or reduce non-point source pollution.

To provide environmental protection and improvement emphasis for water and soil resources and water-related beneficial uses, the National Non-point Source Policy (December 12, 1984), the Forest Service Non-point Strategy (January 29, 1985), and the USDA Non-point Source Water Quality Policy (December 5, 1986) were developed. Soil and water conservation practices were recognized as the primary control mechanisms for non-point sources of pollution on National Forest System lands. This perspective is supported by the Environmental Protection Agency (EPA) in their guidance, "Nonpoint Source Controls and Water Quality Standards" (August 19, 1987). B. Forest Service Manual Sections 2532.02, 2532.03 Sections 2532.02 and 2532.03 of the Manual describe the objectives and policies relevant to protection (and where needed, improvement) of water quality on National Forest System lands so that designated beneficial uses are protected. Guidelines for data collection activities (inventory and monitoring) are also described (USDA 1990). C. Executive Orders 11988, Floodplain Management, and 11990, Protection of Wetlands On National System Forest lands, streamside and wetland protection typically exceeds the Floodplain Management and Wetland Protection orders by meeting the Riparian Habitat Conservation Area (RHCA) guidelines described in INFISH (USDA 1995), which is an amendment to the Lolo National Forest Plan. Executive Order 11988 requires that agencies avoid, to the extent possible, adverse impacts associated with occupancy and modification of floodplains. It applies to all floodplain locations, as a minimum to areas in the 100-year, or base floodplain (Executive Order 1977). Executive Order 11990 states that agencies shall minimize destruction, loss, or degradation of wetlands and shall preserve and enhance their natural and beneficial values. Agencies are to avoid construction in wetlands unless it is determined that there is no practicable alternative and that all practicable measures are taken to minimize harm to wetlands (Executive Order 1977).

State Regulations A. Montana Water Quality Act (Title 75, Chapter 5, Montana Code) as revised

October 1999 The Lolo NF participates with the Montana DEQ towards the protection of water quality through the application of BMPs, water quality data collection, and implementation of TMDLs and WQRPs.

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The Montana Water Quality Act describes water quality management requirements, water classifications, and water quality standards for the State of Montana. It is the document that describes the water quality permitting and enforcement powers delegated by EPA to states under the federal Clean Water Act. Montana DEQ is the agency responsible for administration of the Act. The following documents contain the specific water quality standards enforced by MDEQ:

• Montana Surface Water Quality Standards and Procedures [Administrative Rules of Montana (ARM) 17.30.601-670], as of June 2006.

• Montana Numeric Water Quality Standards (Circular WQB-7, February 2008). Applicable water quality standards are cited in the Water Quality section of this report.

The State of Montana maintains the "Waters in Need of TMDLs (303(d) list) and TMDL Priority Schedule" (Montana DEQ, http://cwaic.mt.gov). The water quality listings are reassessed on a 2-year cycle. Water bodies that are partially supporting or not supporting their beneficial uses are considered to be impaired and failing to achieve compliance with water quality standards. Where water bodies are threatened, partially supporting, or not supporting beneficial uses, actions influencing water quality must lead to an improvement in the watershed conditions influenced by the activity.

B. State of Montana Best Management Practices for Forestry and Streamside Management Zone Law and Rules

On National System Forest lands, streamside protection exceeds the SMZ law by meeting the Riparian Habitat Conservation Area (RHCA) guidelines described in INFISH (USDA 1995), which is an amendment to the Lolo National Forest Plan. The Montana Department of Natural Resources and Conservation (DNRC) is responsible for oversight of forestry and road management practices to protect resources in Montana. Best Management Practices (BMPs) for water quality in Montana (MSU 2001) are voluntary, preferred measures to protect soil and water quality. They are developed for both riparian and for upland management. The Forest Service uses BMPs as mandatory minimum measures for protecting watershed resources, and generally exceeds the minimum efforts required by State law. In addition, there is a Memorandum of Understanding between the U.S. Forest Service, Montana Department of State Lands, Plum Creek Timber Company, Bureau of Land Management, Bureau of Indian Affairs, Flathead Agency, Department of Natural Resources and Conservation, and Department of Health and Environmental Sciences (now MDEQ) for adopting and implementing Best Management Practices for Forestry in Montana. This memorandum direction went into effect April 1987, and provides that the parties agree to incorporate Best Management Practices into their forest operations in order to minimize or prevent adverse water quality impacts. Lolo NF Best Management Practices, which are also mandatory, equal or exceed the protection afforded by Montana BMPs.

Streamside Management Zone (SMZ 2005) rules are mandatory for timber sales, applying within the SMZ, which is “…a strip at least 50 feet wide on each side of a stream, lake, or other body of water, measured from the ordinary high water mark, and extending beyond the high water mark to include wetlands and areas that provide

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additional protection in zones with steep slopes or erosive soils” (Logan 2001). In the context of the SMZ rules, a stream is a natural watercourse with a defined channel, flowing either continuously or intermittently. Isolated wetlands, lying within a sale boundary but outside SMZ boundaries, are not regulated under the SMZ law. Under the law, specified activities associated with timber harvest—including broadcast burning, clearcutting, vehicle operation (except on established roads), road construction (except at crossings), and other activities—are prohibited in SMZs unless approved by the DNRC. SMZs are not necessarily full-fledged buffers, but special measures are taken in the Zone to protect the special values found there.

C. Montana Stream Protection Act—SPA 124 Permits; Short-term Exemption from Montana’s Surface Water Quality Standards (3A Authorization)

The Lolo NF participates in the 124 permit process with the Montana Department of Fish, Wildlife & Parks when Forest construction projects affect any stream bed and/or bank areas (e.g., culvert and stream rehabilitation projects). If during construction stream turbidity and sediment loads are anticipated to exceed state water quality standards, a 3A authorization is acquired from the Montana DEQ.

Activities that would physically alter the bed or immediate banks of a stream require permits under the Montana Stream Protection Act (1991). Such activities proposed by federal, state, county, and city government agencies require an SPA 124 permit from Montana Fish, Wildlife & Parks - this is the counterpart of the 310 permit required from DNRC for projects proposed by private individuals. Land ownership does not necessarily determine which permit is needed; rather, the party in charge of the project determines permitting requirements. SPA 124 permits are required for new construction or for modification, operation, and maintenance of an existing facility, and may apply to intermittent drainages as well as perennial streams. Culvert removal and replacement, stream channel rehabilitation, and other such actions are examples of activities that would require these permits.

If construction would cause unavoidable short-term violations of state water quality standards (mainly sediment), a 3A Authorization needs to be obtained from MDEQ.

Lolo National Forest Plan Forest hydrologists review proposed projects for compliance with the Forest Plan in relation to the maintenance or improvement of water quality, quantity, and functional hydrologic systems. The Lolo National Forest Plan (1986) guides management activities on the Forest through the designation of 28 management areas, each with specific resource goals, objectives, and standards. The basis for the Forest Plan is the National Forest Management Act of 1976. Under the Plan, watershed protection standards exist which emphasize water quality, water quantity, and maintenance of hydrologic functions. Water bodies and riparian areas are designated primarily as Management Area 13 (MA 13).

A. Goals and Objectives Goal #4: Provide a pleasing and healthy environment, including clear air, clean water, and diverse ecosystems. (Lolo NF Plan, page II-1) Goal #8: Meet or exceed State water quality standards. (Lolo NF Plan, page II-1)

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Objective 1, p.II-2: : “…improves the environmental quality of the Forest over current direction through strong Forest goals, Forest-wide standards, Management Area standards and direction, and an extensive, affordable Monitoring Program that emphasizes protection of water quality…”

B. Standards and Management Area Direction Forest Standard 15: “Application of Best Management Practices (BMPs) will assure water quality is maintained at a level adequate for protection of National Forest resources and meets or exceeds Federal and State standards.” (page II-12) Forest Standard 17: “A watershed cumulative effects analysis will be made of all projects involving significant vegetation removal prior to these projects being scheduled for implementation. These analyses will also identify existing opportunities to mitigate adverse effects on water-related beneficial uses, including capital investments for fish habitat or watershed improvement.” (page II-12)

Forest Standard 19: “Human-caused increases in water yields will be limited so that channel damage will not occur as a result of land management activities.” (page II-12)

MA 13 Direction (pp. III-56-59) Provides goals and standards for protection and management of water and riparian resources including:

MA 13 Standard 9: “Riparian vegetation, including overstory tree cover, will be left along water bodies as needed to provide shade, maintain streambank stability, desirable pool quality and quality for aquatic organisms, and promote filtering of overland flows.” (p. III-57)

MA 13 Standard 10: “All management activities, especially those that involve earth moving, will be designed to minimize impacts on water quality and other riparian values. Project prescriptions will be developed by an interdisciplinary team, including specialists in soils, hydrology, engineering, wildlife, and fisheries biology, and silviculture.” (p. III-57)

MA 13 Standard 12: “Generally, new roads in riparian zones will be minimized. Exceptions would be areas where road systems must obviously cross or traverse these zones or where total resource needs require road access.” (p. III-58)

MA 13 Standard 13: “Roads will be managed…to avoid damage to drainage systems and resource values. Roads will be constructed and managed in a manner to keep sedimentation hazard low.” (p. III-58)

MA 13 Standard 24: “Where needed, fish passage will be provided for in stream crossings by maintaining natural flow velocities and channel gradients existing at the crossing site.” (p. III-59)

Implementation, Project Planning: “As part of project planning, site-specific water quality effects will be evaluated and control measures designed to insure that the project will meet Forest water quality goals; projects that will not meet State water quality standards will be redesigned, rescheduled, or dropped.” (p.V-2)

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MA 28 Direction (pp. III-144-149) Provides goals and standards for the Rattlesnake National Recreation Area, including the following pertinent to water resources:

MA 28 Goal 2: “Provide for acceptable levels of water quality in the municipal watershed.” (p. III-144)

MA 28 Standard 4: “All management activity, especially those that involve earth moving, will be designed to minimize impacts on water quality and other riparian values.” (p. III-145)

MA 28 Standard 9: “Streamside vegetation will be managed for shade and filtering of overland flows.” (p. III-145)

MA 28 Standard 17: “The Sawmill Gulch Road, including the existing parking lot, will be treated to reduce the siltation into Rattlesnake Creek.” (p. III-146)

MA 28 Standard 18: “Hard surfacing will be utilized on the Rattlesnake Parking Area and access road to reduce dust and road surface run-off to Rattlesnake Creek.” (p. III-146)

MA 28 Standard 19: “Overnight camping will not be permitted within three miles of the Rattlesnake trailhead due to the additional sanitation needs required and associated risk of contamination of the watershed.” (p. III-146)

MA 28 Standard 20: “Vault toilets will be provided at heavy day use sites to minimize the risk of human waste contaminating Rattlesnake Creek.” (P. III-146)

C. Inland Native Fish Strategy (INFISH) The Lolo National Forest Plan was amended based upon recommendations made in INFISH (USDA 1995). This amendment restricts certain types of management activities on forest riparian systems, with the objective of maintaining or improving habitat for inland native fish species. It designates priority watersheds for monitoring, restoration, and watershed analysis; identifies default riparian management objectives (RMOs); and establishes riparian habitat conservation areas (RHCAs) around all streams, wetlands, water bodies, and landslide prone areas. See the Fisheries Specialist’s Report for a discussion of this amendment to the Forest Plan.

D. Rattlesnake National Recreation Area and Wilderness Limits of Acceptable Change based Management Direction (Forest Plan, Appendix O-4)

Appendix D of this management direction has the following stipulations based upon the Montana Water Quality Standards: There are two parts to the Montana Water Quality Standards: classifications and standards. Rattlesnake Creek is classified by the State of Montana as “A Closed”. The standards for this classification are:

1) Waters classified A-Closed are suitable for drinking, culinary, and food processing purposes after simple disinfection.

2) Public access and activities such as livestock grazing and timber harvest are to be controlled by the utility owner under conditions prescribed and orders issued by the department.

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3) For waters classified A-closed the following specific water quality standards shall not be violated by any person:

a. The geometric mean number of organisms in the coliform group must not exceed 50 per 100 milliliters.

b. Dissolved oxygen criteria are not applicable for the classification. c. No change from natural pH is allowed. d. No increase above naturally occurring turbidity is allowed. e. No increase above naturally occurring water temperature is allowed. f. No increases are allowed above naturally occurring concentrations of

sediment, settleable solids, oils, or floating solids, which will or are likely to create a nuisance or render the waters harmful, detrimental, or injurious to public health, recreation, safety, welfare, livestock, wild animals, birds, fish, or other wildlife.

g. No increase in true color is allowed. h. No increases in toxic or other deleterious substances, pesticides, and

organic and inorganic materials including heavy metals, above naturally occurring concentrations, are allowed.

i. No increases in radioactivity above natural background levels is allowed.

Analysis Data Sources and Methods Analysis watersheds are delineated along hydrologic boundaries using GIS and roughly correspond to 6th and 7th code HUCs using the NRCS classification of hydrologic units (USGS and NRCS 2009). Additional GIS layers included: proposed project activities, Forest Plan Management Areas, streams, existing roads and trails, fire and timber harvest histories, land ownership, topography, precipitation, and the forest land systems inventory (soils, landforms, etc). Site visits occurred during the 2009, 2010, and 2014 field seasons. Site visits were made to view current stream and riparian conditions and to view road and stream interactions. Field crew efforts related to hydrology involved the survey of stream reaches along Rattlesnake Creek, Marshall Creek, and Marshall Creek headwater tributaries in the proposed project area. The Montana DEQ’s Clean Water Information Act website (http://cwaic.mt.gov/) was consulted for additional stream inventory and water quality information that the State has compiled for the project area.

Roads and Road Density Methods Road density is the ratio of the length of roads per unit area and is usually reported in miles per square mile (mi/mi2). Road density is one measure used to assess the potential impacts of roads on water quality and quantity and is calculated using GIS layers of mapped roads and analysis areas. Research demonstrates that unpaved forest roads represent a source of sediment (USDA Forest Service 2000, Ercelawn 1999). Sediment contributed from roads and delivered to streams can affect water quality, habitat, sediment transport regimes, and channel morphology. The USDA Forest Service classified road density in examining the characteristics of aquatic/riparian ecosystems in the Columbia River Basin (CRB) (1996). Watersheds with

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greater than 4.7 mi/mi2 have an “Extremely High” road density. “Very Low” road density is defined by 0.02 to 0.1 mi/mi2 (Table 1). The CRB study found that as road density increases, the ability of the watershed to support strong populations of key salmonids is diminished (USDA Forest Service 1996).

Table 1. Road Density Classification (USDA 1996) Classification Road Density (miles/mile2)

Extremely High > 4.7 High 1.7 - 4.7 Moderate 0.7 - 1.7 Low 0.1 - 0.7 Very Low 0.02 - 0.1

Research shows that roads interact with surface and subsurface flow of water over hillslopes. This interaction may affect the hydrologic response of a watershed, including the timing and magnitude of the hydrograph. Wemple and Jones (2003) found that depending on the nature of storm events, watershed characteristics, and road segment attributes, storm flow response may be more rapid and have greater peaks because of the effect roads have on hillslope flow. Road density as estimates of watershed health are limited by two basic issues: 1) the accuracy of mapping; and, 2) roads have unequal effects depending on a variety of factors. Roads that have grown in and have some level of natural recovery but are mapped may be represented as equal to open roads. Roads with higher slope positions, on ridgetops, or away from streams are likely to have a much lesser impact on water quality than roads in valley bottoms, along streams and riparian areas, and roads that have stream crossings. Different road jurisdiction and management may correspond to different types and degrees of impacts also. To address some of these limitations, other road measurements such as road encroachment are used to refine the context of density.

Road Encroachment Road encroachment was used to refine the road density analysis. Road encroachment measures provide additional evaluation of current watershed conditions with respect to controllable sediment sources, hydrologic functions (e.g., large woody debris utilization), and possible direct, indirect, and cumulative impacts. GIS data were used to calculate road proximities to water courses, including crossings. The amount of road adjacent to stream courses is a very important indicator of possible road impacts. Among the other parameters evaluated by USDA 2000 was the length of stream with roads within 300 feet and 100 feet. Roads within these stream buffers impact sediment delivery and large woody debris recruitment potential, and thus aquatic habitat. Roads immediately adjacent to streams can affect channel hydraulics, floodplain capacity, and other stream dynamics. The 300-foot buffer is based on a review of a large body of research on sediment delivery distances (Belt et al. 1992, Frissell 1996, Furniss et al 2000, McDonald and Stednick 2003). These reviews concluded that sediment sources within 300 feet of a water body

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have higher probabilities of delivering sediment into the water bodies. The 100-foot buffer is based on the average height of the tree species (cottonwood, spruce, etc.) most commonly found in riparian areas on the Lolo NF. Roads within 100 feet of streams preclude the growth of trees within the road template (often from top of cutslope to toe of the fillslope), decreasing the density of trees in the riparian area, and thus precluding the number of trees available for large woody debris recruitment and stream shade. The most direct hydrologic connection between roads and stream channels occurs at road/stream crossings because of the minimal amount of vegetative filtering occurring at these sites (Taylor et al. 1999; Furniss et al 2000). Road encroachment data, including crossings, were used for input to the sediment delivery models.

Sediment Delivery Modeling Project activities with the potential of affecting sediment delivery, primarily road and silviculture activities, were modeled as potential sources of fine sediment. Intermittent streams are included because of their importance in carrying stored sediment during times of peak runoff. Model analysis results for sediment yields should not be interpreted as absolute values, but as comparison between the existing condition (no action) and the action alternatives.

The WEPP model (Water Erosion Prediction Project Tool, Elliot et. al. 1999) was used for road sediment delivery modeling. The WEPP model predicts what sediment would enter stream courses, or drainages leading to stream courses. WEPP predictions are generally within the range of actual field observations of sediment yields (USDA 2000). Sediment load values for culvert removals were based on field data collected on the Lolo NF (Casselli et al. 1999), while potential savings for culvert removal or upgrade are estimated at half the amount of road fill currently present at a site. All model results are generated for trend and magnitude comparisons and should not be considered absolute values.

Water Yield Modeling The equivalent clear-cut area (ECA) model was used for evaluation of current water yields and possible direct, indirect, and cumulative impacts. Methods for determining the effects of vegetation removal on water yield in areas with snowmelt-dominated runoff have been developed for the Lolo NF (Pfankuch 1973) and reviewed and refined for US Forest Service Region One. The basis of the ECA analysis is that water yield increases when vegetation is removed, whether by natural disturbance such as fire, or by human disturbance. ECA analysis is commonly used as an indicator of the extent to which watershed vegetation has been altered by past and proposed management activities. As a conservative measure, an assumption is made that roads are not recovered hydrologically and are assigned a recovery value of zero. For timber harvest there is a continuum of recovery values as the stand ages. Water yield increase is greatest immediately following vegetation removal. In years subsequent to vegetation removal,

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the ECA (and water yield increase) declines, or “recovers,” because of vegetation re-growth. This regrowth relationship is expressed as a recovery curve. This assessment analyzes ECA results in context with ranges of historic stand and watershed conditions prior to fire suppression. The Timber Stand Management Record System (TSMRS) database for the Lolo NF was queried to obtain all records of documented timber harvest. GIS data for roads, trails, and fire were also evaluated.

Affected Environment

Analysis Area and Landownership The Marshall Woods analysis area encompasses the Middle and Lower Rattlesnake Creek and the Marshall Creek watershed 7th code HUC (Figure 1). The analysis area for assessing the effects to water resources is expanded beyond the project area boundary to include the entire watershed areas in the middle and lower Rattlesnake Creek HUCs. Cumulative effects are considered for the above HUCs, as well as for conditions affecting Rattlesnake Creek above the project area boundary. This area covers just over 28,500 acres. Much of this analysis area is owned by the U.S. Forest Service (70%), with the remaining area under private and state ownership (30%). The majority of private lands are within the Lower Rattlesnake Creek and Marshall Creek watersheds (Figure 1). Table 2 displays land ownership acreages within the analysis area for watershed effects. This analysis area was chosen as it takes into account all connected activities within a geographically discrete and hydrologically connected area (watershed).

Table 2. Marshall Woods Analysis Area for Water Resources Effects and Land Ownership.

Ownership Acreage

Middle Rattlesnake Creek HUC

Lower Rattlesnake Creek HUC

Marshall Creek HUC

Forest Service 15,319 2,735 2,016 Private 38 5,057 3,209 State of Montana - 87 31 Plum Creek - - 9 Water 9 3 -

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Figure 1. Marshall Woods Analysis Area for Effects to Water Resources

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Climate and Hydrology Elevations within the analysis area range from approximately 7,971 feet at Stewart Peak to 3,200 feet at the confluence of Rattlesnake Creek with the Clark Fork River. Mean annual precipitation ranges from approximately 15 inches at lower elevations to more than 50 inches on the highest peaks. The most precipitation is received November through June, with snowfall accumulation at higher elevations in the winter months (NRCS 2011).

Rainfall, snow melt, and groundwater are the primary components of stream flow. Available snowmelt is typically the main source of rise and fall in the spring and summer hydrograph. Rain-on-snow events are possible during winter months as a result of warm Pacific air masses, and can result in elevated stream flows. Peak flows typically occur in May or June, with bankfull flows estimated at about 1,300 cfs near the mouth of Rattlesnake Creek and about 20 cfs near the mouth of Marshall Creek (USGS 2011). During other times of the year, flows decrease substantially and generally are the result of released soil moisture and groundwater discharges.

Wetlands Wetlands are “…areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions” (U.S. Army Corps of Engineers 1987). Wetlands are delineated based on hydrology, soils, and vegetation characteristics. Swamps, bogs, marshes, and wet meadows are examples of wetlands. Updates to the U.S. Fish and Wildlife Service’s National Wetland Inventory have been completed recently for the analysis area (MTNHP 2010). Wetlands observed during the field inventories were primarily associated with riparian areas and did not qualify as jurisdictional wetlands.

Stream Channels A. Rattlesnake Creek

For the Marshall Woods project, general stream reconnaissance was conducted on portions of Rattlesnake Creek within the project area during the 2009 and 2010 field seasons. Most of the creek in the project area is sinuous pool and riffle sequence with access to its floodplain (Rosgen C3 with some confined sections and side channels). The creek has a fairly healthy riparian corridor with abundant acting and potential large woody debris. During 2009 some excessive algae growths were observed in slower moving water areas. Bank erosion was observed in areas where the stream cuts into terrace elevations or the valley wall, although these areas were relatively infrequent and related to natural channel processes. Bank erosion and soil compaction areas were also observed where multiple trails come near or follow the streambank. Most of the trail-related impacts correspond to the mapped trail system (Figure 2). Overall, bank trampling and erosion associated with trail use is localized. Through much of the Middle Rattlesnake HUC the main travel route, Road/Trail 99, lays above the floodplain of

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Rattlesnake Creek. The position of the Road/Trail 99 and its low gradient limit sediment delivery to the creek. Spring Gulch is the only perennial tributary (third-order) to Rattlesnake Creek within the project area. There is a PIBO (Pacfish-Infish Biological Opinion) monitoring site near the mouth that is treated as a “reference” site, representing a minimally managed condition. Within the Lower Rattlesnake HUC, Woods Gulch is the only tributary to Rattlesnake Creek with intermittent surface flow (all other mapped tributaries are largely ephemeral). Woods Gulch is a second-order stream with a steep gradient and fairly confined floodplain. The Marshall Ridge Road (Rd #16803) crosses the upper portion of Woods Gulch and contains an undersized culvert. An additional undersized culvert is above this crossing on Rd #53414. Forest Trail 513 follows along the terrace above (and in a few sections the floodplain of the stream) for much of its length and is in need of maintenance to improve drainage. Near the lower section of the stream, the Woods Gulch Road (County and Forest Service maintained) is in close proximity to the stream and is also in need of drainage improvements. Most of the stream flow from Woods Gulch is captured in an irrigation ditch and does not deliver via surface connection to Rattlesnake Creek.

B. Marshall Creek The mainstem of Marshall Creek is in a narrow, high gradient valley, with some floodplain area (Rosgen B type). There are at least two small impoundments on mainstem Marshall Creek, one just upstream and one just downstream of the main road crossing for the Marshall Mountain Ski Area. For much of the mainstem, riparian vegetation provides shading and energy dissipation. Marshall Creek has occasional raw eroding banks where it cuts into the adjacent valley walls, although these banks rarely continue for more than 10 to 30 feet in length at a time. The most notable impacts to Marshall Creek were from County Road 357, which parallels the creek from near the confluence with the Clark Fork River to approximately 2.5 miles upstream. Road 357 encroaches on the channel and reduces the creek’s floodprone width. The 357 crossing is undersized above the junction with Forest Rd #2122 and is causing localized scour and bank erosion. The Forest Rd #2122 crossing is misaligned and undersized and is also affecting the channel. Undersized culverts have also been located on the two northwestern most perennial tributaries to Marshall Creek where Rd #16783 crosses them and along the northeastern most intermittent tributaries where Rds# 53033 and 63233 cross them. A recent mudslide in August of 2014 deposited a large amount of material from the State highway that runs along the base of Marshall Creek and Marshall Mountain Road into the Clark Fork River. The fish ladder that was installed by MT Fish and Game was not damaged but this did likely do some damage to the stream channel. Rd #33350 is not drivable and also has a well-worn single track that likely connects to the private road system in the upper reaches of Marshall Creek and Marshall Mountain Ski Area. Mountain bike traffic uses this road, as evidenced by a single 2x6 inch board used at a tributary crossing (Figure 2). There is no CMP at this crossing. The valley is quite steep, in excess of 10%, yet the stream bottom is relatively flat on the upstream side of

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Rd #33350, indicating a prolonged period of deposition. The channel has a one foot high head cut on the downstream end of the road prism. The total road fill at this crossing is estimated to be 10 cubic yards. The crossing appears to be in a stable state with vegetated banks. The approaching trails and some bare ground to the side are minor sediment sources. The road parallels the stream below this crossing but does not appear to be contributing sediment and has a well-vegetated buffer.

Figure 2. Looking upstream at Rd #33350 crossing Marshall Creek tributary.

Based on an analysis of recent stream reach surveys, project streams and riparian areas show impacts from ‘chronic’ disturbances and appear to be on a static or slightly upward trend towards recovery. Recovery potential depends on the stream type and has a wide range of responses (Rosgen 1996). Streams in this analysis area generally have “good” to “excellent” recovery potential from most impacts, with active restoration required to mitigate chronic sources.

Water Quality Rattlesnake Creek is listed by MDEQ as a Water Quality Limited Segment (WQLS), due to impairments from flow alterations (Table 3). Beneficial use support for Primary Contact Recreation has not been fully assessed. Currently the calculation of a Total Maximum Daily Load (TMDL) for Rattlesnake Creek will not be required, because the cold water fishery impairment results from pollution (i.e., not quantifiable) versus a pollutant such as metals, sediment, or temperature. (A TMDL is a pollutant budget identifying the maximum amount of a particular pollutant that a water body can assimilate without causing applicable water quality standards to be exceeded.)

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Table 3. Excerpt of the 2010 303d Listing for Streams within the Analysis Area (Montana DEQ, http://cwaic.mt.gov/).

Stream Miles Impaired Uses

Use Support

Probable Cause Probable Source

Fully

Thre

aten

ed

Part

ial

Not

Su

ppor

ting

Rattlesnake Creek 23.6

Cold Water Fishery

Other flow regime alterations

Dam Construction (Other than Upstream Flood Control Projects) Flow Alterations from Water Diversions

Miles = number of miles listed Impaired Uses = the beneficial uses of the segment which are impaired Probable Cause = the most likely cause of the beneficial use impairments listed under “Impaired Uses”. Proper implementation of the required Lolo NF resource protection measures for the Marshall Woods project is essential for complying with State and federal laws for ensuring that water quality is maintained or improved.

Source Water Mountain Water Company holds senior water rights in the Rattlesnake watershed totaling almost 800 million gallons of water. In addition to their water supply dam on lower Rattlesnake Creek, much of this water is stored behind dams on eight lakes high in the Rattlesnake Wilderness: Glacier, Little, Big, Carter, Sheridan, Worden, Sanders, and McKinley lakes. One of the reasons for the creation of the Rattlesnake Wilderness and National Recreation Area was to protect “clean, free-flowing waters stored and used for municipal purposes” (MWC 2011). Today the Rattlesnake watershed serves as a back-up water supply source for the City of Missoula, because the city’s drinking water now comes from high capacity wells in the Missoula Valley. As mentioned above for the protection of water quality, Mountain Water Company is given authority by the state to limit access and potentially other beneficial uses in the watershed (ARM 17.30.621).

Roads Roads have different influences on stream function and sediment deliveries depending on a variety of conditions such as hillslope position, road age and design, soil saturation, geologic substrate, vegetation, and climate. Generally road segments with surfaces and culverts that drain directly to streams and those that cross the downslope side of clearcut areas are most likely to contribute significantly to runoff and sediment delivery (Wemple and Jones 2003).

A. Road Density Table 4 displays total road density within the analysis area watersheds. The Middle Rattlesnake Creek HUC has a “Low” road density rating, while the Lower Rattlesnake

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Creek HUC and the Marshall Creek watershed have road densities that are “Extremely High” according to the findings of CRB (USDA 1996). Lolo NF data indicate similar findings as the CRB assessment because streams were found to show road effects when road densities approached two miles per square mile or more (Riggers et al. 1998). Most of the roads in the the Middle Rattlesnake Creek HUC are under Forest Service jurisdiction, while private and county roads are the majority of mileage in the Lower Rattlesnake Creek HUC and the Marshall Creek watershed. Table 4. Existing Total Road Densities

Watershed HUC

Total Road Miles

HUC Area (Mi2)

Road Density

CRB Road Density Rating

Percent of Roads Under USFS Jurisdiction

Middle Rattlesnake Creek

8.1 (FS 7.4) 24 0.3 Low 91%

Lower Rattlesnake Creek

70 (FS 12 ) 12.3 5.7

Extremely High

17% (increase of 4% due

to recent land acquisition)

Marshall Creek

59.4 (FS

15.5) 8.2 7.2 Extremely

High

26% (increase of 14% due

to recent land acquisition)

B. Road Encroachment

Although total road densities are high in the analysis area, there is a difference in the effects that a road can cause based upon proximity to water. Roads within 300 feet of streams can impact sediment delivery, aquatic habitat, and stream temperature. Depending on road condition, terrain slope, and buffer conditions, among others, roads within 300 feet have higher probabilities of sediment delivery over time (Belt et al. 1992). One hundred feet is a good indicator of potential road influence on wood recruitment (i.e., pool formation and cover, energy dissipation) and shading because it approximates an average maximum tree height on the Lolo NF. Table 5 displays road proximities along with the associated road crossings within the analysis area. These adjacent segments of roads are likely to influence sediment loads, riparian vegetation, bank stability, stream habitat, and shading. Stream crossings have the highest potential to deliver sediment to streams and may be more impactive when undersized because stream channel stability is affected (e.g., accelerated bank erosion and scour). GIS analysis of roads reveals that roads encroach within potential sediment delivery distances and riparian areas in all three watersheds. The Marshall Creek watershed has the greatest amount of roads within both 300 feet of streams (11.1 miles) and 100 feet of streams (4.5 miles). Streams are crossed within the Middle Rattlesnake HUC about 0.3 times for one square mile of road, with values increasing to 1.2 times in the Lower Rattlesnake HUC and 4 times in the Marshall Creek watershed.

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Table 5. Existing Road Encroachment and Associated Road Crossings.

Watershed HUC

Total Road Miles

Road Miles Within 100

Feet

Road Miles Within 300

Feet

Road Crossings

Count Density (#/mi2)

Middle Rattlesnake Creek

8.1 (FS 7.4)

0.6 (FS 0.6)

3.1 (FS 3.1) 7 0.3

Lower Rattlesnake Creek

70 (FS 12 )

1.7 (FS 0.5)

7.0 (FS 2.3) 15 1.2

Marshall Creek 59.4

(FS 15.5 ) 4.5

(FS 1.1) 11.1

(FS 3.5) 33 4.0

Watershed Improvement History Road-stream crossing function, stream channel conditions, channel connectivity, and fish habitat on the Lolo NF have been improved in recent years through completion of several watershed improvement activities. Both on and off-Forest, the Rattlesnake watershed has been the focus of a number of projects. Since 1999, the Forest Service has replaced four culverts with bridges on upper Rattlesnake tributaries. Four irrigation diversions on lower Rattlesnake Creek have had new or updated fish screens installed. In 2001, restoration partnership efforts addressed fish passage at the Rattlesnake main water supply dam with the installation of a fish ladder. In 2002, the City of Missoula and the Greenough Park Advisory Committee sponsored a project on Lower Rattlesnake Creek that reconstructed a side channel of the creek and improved floodplain access. In 2010, the City of Missoula completed mainline construction on the Rattlesnake Valley Sewer Project, a special improvement district to connect the remaining homes in the Rattlesnake to sewer (replacing densely packed septic tanks). Most recently, in 2014 the Forest improved a small area along the Spring Gulch trail that was actively eroding into the creek, and improved and stabilized an area of intensive recreation use and trampling on Rattlesnake Creek near the main Rattlesnake trailhead to minimize a chronic sediment source. Montana Fish, Wildlife and Parks have been working to improve fish passage and habitat in the Marshall Creek watershed, some of which has involved private landowners. These efforts include a fish ladder at the mouth, two culvert replacements on private property, a fish screen, large woody debris additions in four reaches, and riparian fencing on private property.

Water Resource Issues This hydrologic assessment addresses water resource issues and concerns, which are derived from previous assessments, public concerns, and specialist input resulting from public scoping and interdisciplinary team meetings. It does not address issues outside of the scope and setting of the assessment area. The following statements summarize the hydrology-related issues:

• Proposed activities of the Marshall Woods project may affect water quality in both the short and long term, primarily by affecting sediment loading and water yield (specific activities detailed further below). The Upper, Middle, and East Fork

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Rattlesnake Creek HUCs are identified as priority bull trout watersheds (USDA Forest Service 1995). Changes in water quality and stream habitat may affect threatened and sensitive species.

o Proposed road management activities, including BMP upgrades, haul, storage, and decommissioning measures could increase short-term road surface erosion. Fine sediment from road erosion could be delivered at stream crossings and where roads are adjacent to water bodies. Increased sediment delivery may degrade water quality, which can affect stream channel stability, substrate composition, and habitat conditions.

o The current infrastructure, including undersized culverts and unmaintained system and non-system roads pose potential risks of chronic and/or episodic sediment deliveries, particularly following high intensity events such as rain-on-snow and concentrated runoff post-wildfire. Proposed culvert removals, and proposed road decommissioning could reduce road surface erosion and minimize the risk of mass failure and major sediment delivery in the long-term.

o Proposed commercial and non-commercial silvicultural activities, including prescribed burning, in the project area have the potential to increase hillslope erosion primarily in the short-term. Increased sediment delivery may negatively influence water quality, which can affect stream channel stability, substrate composition, and habitat conditions.

o Proposed commercial and non-commercial silvicultural activities, including prescribed burning, would remove vegetative cover, which could potentially affect water yield both in the short and long terms.

• Primary watershed concerns include Rd #33350 and intermittent stream crossing, the Rd #2122 crossing on Marshall Creek, the Rd #16803 crossing on Woods Gulch, the trail along Woods Gulch, and the Rd #17150 crossing of Woods Gulch.

Assessment Indicators Assessment indicators are used to help evaluate the effects of management activities on water resources.

1. Road Influence Indicators, relative to the existing condition • Miles of roads proposed for construction, decommissioning and storage • Change in road density • Change in road encroachment (proximity and crossings) • Change in fine sediment delivery (as modeled by WEPP)

2. Silviculture Influence Indicators, relative to the existing condition • Acres of proposed treatments • Change in fine sediment delivery • Change in water yield relative to existing and historic stand conditions

Many of the assessment indicators are based on GIS data that have varying levels of ground truthing. These data are analyzed within the project area by watershed, and when combined with research information help to form a reasonable foundation for understanding of watershed health and function.

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Data extrapolation in terms of field inventory and modeling requires interpretations that are suitable for general comparison and understanding trends, but may not be completely accurate for all settings. Models simplify extremely complex physical systems and are developed from a limited database. Although specific quantitative values for sediment and water yields are generated herein, the results are used only as a tool in the interpretation of how real systems may respond. Models used herein include Water Erosion Prediction Project (WEPP) and Equivalent Clearcut Area (ECA) tools and methodologies. Both WEPP and ECA methodologies are widely accepted as reasonable interpretation and prediction tools in the dynamic forest environs. Model results are generated for trend and magnitude comparisons and should not be considered absolute values. When evaluating sediment impacts on water resources, use of the terminology ‘short-term’ refers to effects expected to last less than 2 years.

A. Erosion and Sediment Delivery Sediment delivery assessment is complex because sediment is derived from both within and outside of the stream and involves both fine and coarse sediment sizes as well as various input dynamics. Sediment derived from within the stream is derived from bed and bank erosion, which relates directly to stream stability. Sediment derived from outside of the stream generally occurs through normal soil creep, mass wasting, rilling, and gullying from concentrated water flow, and/or erosion of exposed surfaces such as roads. Coarse sediment generally originates from episodic events such as debris flows or road failures. The proposed road storage and decommissioning measures, such as removal of undersized culverts and drainage/infiltration mitigations, would address potential non-stream sediment sources associated with ‘catastrophic failure’ (flooding, post-fire runoff and erosion). Fine sediment delivered from roads often enters streams at unimproved road-stream crossings or where roads closely parallel the stream. Generally, as more drainage ways are crossed, the probability of direct sediment input increases because of the minimal amount of vegetative filtering at these sites. Lower elevation roads are more likely to contribute sediment because of proximity to the stream and a greater accumulation of upslope runoff. Because road surfaces are compacted, water infiltration is limited which potentially speeds runoff and sediment to the stream network. Roads can also convert groundwater to surface water by intercepting subsurface flow in cutbanks and routing it down ditches (Luce and Wemple 2001). Implementation of effective Forestry and Road Best Management Practices (BMPs) “…minimize or eliminate potential water quality effects” (Stednick Ch. 8 in Elliot and Audin 2010). Riparian Habitat Conservation Areas (RHCAs) provide additional protection by providing vegetative buffer zones between activities and the stream. However, watersheds with no roads, where roads are not in use, or have been decommissioned have the lowest percentages of fine sediment in streams (McCaffery et al. 2007). WEPP ROAD was used to assess potential fine sediment delivery to streams for the Marshall Woods Project (Elliot 2005). In order to capture a range of sedimentation rates for the project and watershed areas, multiple WEPP: ROAD Batch model runs were

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constructed to simulate fine sediment loading from open and closed roads, haul routes, BMP measures, road decommissioning, and the stream crossings associated with these conditions. Geographic Information System (GIS) for forest roads and topography and field inventories were used to assign variables required for the WEPP models (see Hydrology Project File for more information). The project’s Soil Scientist has completed an analysis of the potential for erosion from the proposed silvicultural activities: commercial and non-commercial harvest, burning, and associated disturbances. Refer to the Soils Specialist’s Report for a comprehensive review.

B. Water Yield Water yield is a concern to water resources because vegetation loss can potentially influence snowmelt and stream runoff timing and magnitude. When stream flows are outside of normal ranges for long durations, stream morphology is subject to alteration. Studies conducted on the Lolo NF have shown that when about 17% of total tree crown canopy within a watershed is removed, changes in available soil moisture become measurable (Pfankuch 1973). Other research has shown that watersheds having more than approximately 30% of their area in an “equivalent clearcut” condition are considered to have potential for changes in runoff quantities and timing (Burton 1997). A recent compilation of water yield research indicates that ECA values ranging up to 50% have been shown to have no significant change in peak flow for snow dominated harvest zones (Grant et al. 2008). Because of the variability in research findings and model uncertainty, water yield assessment is conducted by verifying results with channel condition assessments and historic stand conditions. No stream instability issues have been observed in the project area as a result of increased water yield. Historical stand conditions in the project area indicate that on average about 14% of the basins were non-stocked from wildfire disturbance and approximately 25% were in seedling and sapling structures (Loskensky 1993, Fischer and Bradley 1987). Therefore, historical ECA was likely near 39%. Current ECA values in the project watersheds are lower than 25% (see Project File).

Desired Water Resource Condition For all streams and water bodies, the desired water resource condition is for instream sediment, woody debris, and stream and riparian structure to function within natural reference ranges (USDA Forest Service 1995).

Water Quality Standards and support of beneficial uses should be attained. For instance, a stream should function during flood events without large increases in land loss, structures on or surrounding streams should have minimal influence on flood flows, and stream habitat should benefit.

Projects should be designed to restore ecosystem health and to improve the likelihood of moving towards or maintaining ecosystem processes that function properly in the long-term (i.e., 50 to 100 years) (USDA Forest Service 1996). To benefit water resources, riparian areas should be resilient, diverse, and function within their site potential and be

24

managed to maintain at least that condition with no downward trends. Ideally, road construction should be avoided in riparian areas (USDA Forest Service 1996).

The Marshall Woods action alternatives would help trend toward these desired water resource conditions in a few ways. The proposed road upgrades, maintenance, storage, decommissioning, and culvert removals and/or replacements would help to reduce surface sediment inputs into streams in the long term. The proposed resizing of culverts, culvert removals, and proposed road decommissioning would minimize the long-term risk of mass failure and major sediment delivery following an episodic ‘pulse’ event (e.g., high intensity precipitation event). Proposed silvicultural treatments could help return water yield to historic levels.

Environmental Consequences This section addresses the direct, indirect, and cumulative effects of the project alternatives relative to water resources. Effects are discussed within the context of current research and take into consideration the project assessment indicators for water issues. Potential effects of the treatment activities are discussed considering all management requirements, resource protection measures, and monitoring requirements (refer to Project File). Cumulative effects are assessed for the watershed areas that are potentially most affected by the proposed actions. Reference the Environmental Assessment for detailed description of project alternatives.

• Alternative A- No Action • Alternative B - Proposed Action • Alternative C –Proposed Action Without Mechanical Treatments in the

Rattlesnake Corridor • Alternative D- Proposed Action Without Mechanical Treatments in the

Rattlesnake Corridor and No Temporary Road Construction (no commercial timber harvest activities)

No Action Alternative – Direct, Indirect, and Cumulative Effects The No Action alternative partially fulfills regulatory and Forest Plan direction because some conditions are within standards, while others, primarily roads, road structures, and forest stands need improvements. With the No Action Alternative, maintenance and BMP work will be performed on the first 3.7 miles of the main Rattlesnake corridor Road 99/ Trail 515 including:

• Roadside brushing for safety and to enhance operational feasibility. It would be kept as naturally appearing as possible. In general, trees larger than 6” dbh within 3 feet from the driving surface would not be cut. Slash would either be hand-piled or treated in the same manner as adjacent treatment areas. Slash could also be used for building slash filter windrows near creeks in areas where needed.

• Stream access would be eliminated at MP 0.3 and 0.315 (which is an existing crib wall location on both sides) by placing slash on these areas.

• Stream access at the Spring Creek Bridge (MP 0.50) would be maintained but the surface would be hardened by reinforcing the abutments (e.g., placing 4-6” rip

25

rap) and vegetation would be transplanted around the stream edge where possible to prevent sediment from sloughing off from these areas into the creek.

• Spot graveling would occur at numerous locations from MP 0.99 to MP 3.35 using ¾ inch minus material. This equals about 10% of the road length.

• Improve surface drainage by constructing drivable drainage dips (i.e., waterbars) at 4 locations from mile 2.5 to mile 3.4. These drainage features would be constructed so they are easy to negotiate on a bike or a snowmobile with a grooming attachment.

• Over-sized surface cobbles would be removed. • Bioengineered rip rap (cobbles/boulders angular rock that locks together) and

vegetation would be placed on the edges of the abutments of the Frazier Creek Bridge.

• Areas outside the road bed that are disturbed by project activities would be revegetated by seeding and mulching.

Aside from these road maintenance activities as well as the ecosystem maintenance burning approved but not yet implemented (Rattlesnake NRA Wildlife Habitat Improvement and Ecosystem Burning DN, 1997) and 1.2 miles of road decommissioning approved but not yet implemented (Section 31 DM, 2008), this alternative would maintain the existing condition. Fire suppression and wildfire would likely be the predominant influences that drive the existing conditions. Flooding and windthrow are also possible natural influences. Directly, indirectly, and cumulatively, the existing road system would continue to contribute various quantities of fine sediment to project area streams. The current modeled existing condition for road sediment loading is approximately 0.1, 6.8, and 10.3 tons per year in the Middle Rattlesnake, Lower Rattlesnake, and Marshall Creek watersheds, respectively. The activities above will reduce road sedimentation somewhat in the Middle and Lower Rattlesnake watersheds. Undersized culverts would continue to pose risks to stream stability (e.g., road fill scour, channel aggradation, and risk of failure). Tree and shrub growth would continue on infrequently used roads. Water yields in the project area would remain fairly low, unless affected by large-scale wildfire. Additional cumulative impacts are addressed in the Cumulative Effects section below.

Action Alternatives Comparison – Alternatives B, C, and D Alternatives B, C, and D would achieve all requirements of the Lolo National Forest Plan, and other regulatory standards and guidelines. Alternatives B, C, and D propose to restore conditions within Management Area 13 (streams, lakes, and riparian areas), primarily by decommissioning and placing roads into storage, with associated stream crossing rehabilitation; and upgrading undersized culverts. INFISH Riparian Goals and Management Objectives would be improved as a result of these proposed activities, with the most benefits realized in the Marshall Creek watershed. Activities affecting water quality would meet the intent of sections 208, 313, 319, 303, 401, and 404 of the Federal Clean Water Act by fulfilling appropriate permit requirements. Directly, indirectly, and cumulatively, all action alternatives involve short-term sediment delivery from road work, including BMP upgrades and haul, road decommissioning,

26

culvert removals/replacements, and stream rehabilitation; however, long-term benefits (greater than 10 years) to soil productivity, vegetation growth, and stream functions outweigh short-term effects.

1. Road Influence Indicators Proposed changes to the transportation network are summarized by project alternative (Table 6). The main differences among alternatives are proposed haul use and temporary road construction. No haul use or temporary road construction would occur under both the No Action and Alternative D. Haul use mileage is less under Alternative C than Alternative B, because the main Rattlesnake Road/Trail 99 would not be used as a haul route. Routine maintenance would occur along the main Rattlesnake Road/Trail 99 regardless of the Marshall Woods Project (analyzed under all alternatives). Water resources benefits of the Marshall Woods project result from a combination of road BMP improvements, road decommissioning, road storage, and culvert removals/replacements. Haul Roads and BMPs Proposed haul route mileage is one of the main differences between the alternatives (Table 6). Haul use would occur only under Alternatives B and C, with less haul proposed under Alternative C because the main Rattlesnake Road/Trail 99 would not be used as a haul route. Modest sediment loading increases are expected (<4 years); however, the advantage to haul route use is the application of sediment reducing BMP measures. Therefore road miles treated with BMPs would have reduced sediment delivery in the long-term (multiple years post-haul). For all action alternatives, BMPs would be upgraded or installed along haul roads to minimize potential sediment effects to water resources. Road activities related to haul use would be completed prior to log hauling. Routine maintenance would occur along the main Rattlesnake Road/Trail 99 regardless of the Marshall Woods Project. BMP upgrades include addressing scour/erosion at the Spring and Frazier Creek bridges, spot graveling, and increasing drainage frequency. Table 6. Proposed Haul routes and associated BMPs.

Watershed Activity (miles) Alternative

B C D

Middle Rattlesnake Creek Haul Roads 2.9 0 0 BMP upgrades 2.9 2.9 2.9

Lower Rattlesnake Creek Haul Roads 3.0 1.0 0 BMP upgrades 3.0 1.0 0.8

Marshall Creek Haul Roads 3.9 3.9 0 BMP upgrades 3.9 3.9 0

Temporary Roads Temporary Road mileage is another difference between the Alternatives (Table 7). Temporary roads would be constructed under Alternatives B and C in the Woods Gulch

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area (mid-slope and away from water resources). Temporary roads are expected to be in use for up to two seasons, and no sediment loading to water resources is expected. Table 7. Proposed Changes to the Transportation Network.

Road and Trail Treatments -- All Action Alternatives (B, C, & D)

Proposed Treatment Middle

Rattlesnake HUC

Lower Rattlesnake

HUC

Marshall Creek HUC Approx. Miles

Decommission unneeded roads 0 1.7 5.6 7.3

Add existing road to official road system (not stored) 0 1.1 0 1.1

Add existing road to official road system and Store until needed 0 0 4.8 4.8

Convert Road to Trail 0 1.1 0.3 1.4

Store system roads until needed 0 0 1.9 1.9

Re-align, add to official road system, and Store 0 0.1 0 0.1

Add existing trails to official trail system 0 0.4 0 0.4

Construct System trail to connect Road 53414 (to be converted to trail) to Road 2122

0 0 0.2 0.2

Obliterate the non-system trails in the north portion of sec. 36 0 4.9 0 4.9

Culvert Removals 0 2 17 19 Culvert Replacements 0 1 2 3

Road and Trail Treatments -- Alternatives B & C only Construct Temporary roads 0 1 0 1

Reconstruct non-system road for temporary road 0 0.1 0 0.1

Road Decommissioning Road miles proposed for decommissioning are equal among all action alternatives (Table 7). Additionally under the No Action alternative, there is 1.1 miles of road decommissioning in the Lower Rattlesnake watershed which is a reasonably foreseeable action (approved in the 2008 Section 31 Decision Memo), and is analyzed for all alternatives. About 0.2 miles in the Lower Rattlesnake watershed and 0.3 miles in the Marshall Creek watershed are within Management Area 13 (streams, lakes, and riparian areas). Rehabilitating stream and riparian areas through road decommissioning would assist with meeting the INFISH Riparian Goals and Management Objectives for these areas.

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Physical road decommissioning would occur following BMP practices that minimize potential sediment effects to water resources. Road decommissioning is expected to contribute to short-term sediment loading during drainage rehabilitation treatments to road prisms, including culvert removals (1 year). Sediment loading reductions are modeled to occur through the hydrologic ‘neutralization’ of these road segments (multiple years post-decommissioning). Road to Trail Conversion Road miles proposed for trail conversion are equal among all action alternatives (Table 7). Additionally under the No Action alternative, there is road to trail conversion in the Lower Rattlesnake watershed which is a reasonably foreseeable action (approved in the 2008 Section 31 Decision Memo), and is analyzed for all alternatives. No miles proposed for trail conversion in the Lower Rattlesnake watershed are within Management Area 13, while 0.4 miles in the Marshall Creek watershed are. Crossing rehabilitation would be required on upper Woods Gulch and the NW headwaters of Marshall Creek before official trail use (Rd #s 53414 and 33350), which would meet INFISH Riparian Goals and Management Objectives for these areas. It is anticipated that long-term sediment delivery from trail use would be lower than open road use, because trail traffic and loads are much lighter. Road Storage Road miles proposed for storage are equal among all action alternatives (Table 7). Proposed storage level III roads would not be open for public use or drivable once treatment activities are complete. Level III storage would involve bringing these roads to a more hydrologically neutral status, such as pulling culverts/rehabilitating drainages, and facilitating infiltration. About 0.1 miles the Marshall Creek watershed are within Management Area 13. Rehabilitating stream and riparian areas through road storage would assist with meeting the INFISH Riparian Goals and Management Objectives for these areas. Culvert Removals and Replacements Proposed culvert removals and replacements are equal among all action alternatives (Table 7). The main difference from No Action and the action alternatives are the 17 culvert removals (decommissioning and storage) and 2 replacements (road to trail conversion and routine inventory) proposed in the Marshall Creek watershed. Change in Road Encroachment (density and proximity) Reductions to road densities from road decommissioning are anticipated in the Marshall Woods project area for all alternatives, including No Action because of previously approved decisions (Table 8). However, no changes would occur in the Marshall Creek watershed unless an action alternative is implemented. Changes within 300 and 100 feet of streams are shown because roads in riparian areas tend to have more effects on water resources. Because there are no changes proposed in the Marshall Creek watershed under the No Action alternative, implementing an action alternative would better align with INFISH Riparian Goals and Management Objectives.

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Table 8. Proposed changes in road density and encroachment*.

Lower Rattlesnake Creek HUC ** Existing Action Alternatives**

Road Density (mi/mi2) 5.7 5.5

Roads within 300 feet of water resources (mi) 7.0 5.0 (-2.0)

Roads within 100 feet of water resources (mi) 1.7 1.2 (-0.5)

Marshall Creek Watershed Existing Action Alternatives

Road Density (mi/mi2) 7.2 6.6

Roads within 300 feet of water resources (mi) 11.1 7.7 (-3.4)

Roads within 100 feet of water resources (mi) 4.5 3.6 (-0.9)

*Changes result from road decommissioning (-). ** These activities would occur regardless of the Marshall Woods project (2008 Section 31 DM). Road Sediment Delivery Assessment The sediment delivery assessment was done using models to generate sediment loads. For all alternatives, increases in road sediment loading for the 10-year timeframe are expected over current conditions; however, these increases are offset when considering the sediment savings from culvert removals (Table 9). Approved actions from the 2008 Section 31 Decision Memo are displayed under Alternative A, the no-action alternative. Therefore, there are no differences between Alternatives A, C, and D in the Middle Rattlesnake watershed, and no differences between Alternatives A and D in the Lower Rattlesnake watershed. When only considering action alternatives, Alternative D would generate the least amount of sediment within the modeled 10-year timeframe, as no haul routes are proposed (Table 9). Under Alternative C, the modeled short-term increases from haul are small portions (<5%) of the total existing loading from roads in the Lower Rattlesnake and Marshall Creek watersheds. Additionally, BMPs applied to haul routes would improve conditions/ reduce sediment delivery on those roads post-timber sale. Overall, there is very little difference between Alternatives B, C, and D. However, Alternatives C and D would both be considered slightly more beneficial than Alternative B. Short-term sediment increases from timber sale road-related activities are displayed separately from ‘other’ road-related activities (Table 9). Timber sale activities would occur as part of a timber sale and are anticipated to occur starting in year 1. ‘Other’ road-related activities would occur when funding is secured to complete these proposed activities and are anticipated to occur starting in year 5. All project activities are expected to occur within a 10-year timeframe. The values presented in Table 9 below are a worst-case scenario as they assume all activities occur simultaneously. Short-term sediment deliveries would not result in

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detrimental stream conditions because: (a) actions would not simultaneously occur; (b) impacts would not occur within one year and would be dispersed over multiple runoff cycles; (c) work and total predicted sediment quantities are further distributed across multiple watersheds; (d) only one portion of a project is active at one time-only a few sections of road are being hauled upon; (e) the most risky period for hauling is in the spring during breakup, which occurs at slightly different time periods due to elevation and aspect so only sections of road are at risk from breakup conditions at any one time; (f) the risk of haul-related sedimentation occurring for more than a few days is very small because the timber sale administrator and/or aquatics specialists visit the project area several times each week, especially when conditions are questionable, and would stop the hauling if conditions were unfavorable. Middle Rattlesnake Creek WEPP modeling in the Middle Rattlesnake Creek watershed shows that overall low amounts of sediment are generated from Road 99/Trail 515 and because of this the increase from activities are presented as large percentages (Table 9). Routine maintenance would occur along the main Rattlesnake Road 515/Trail 99 regardless of the Marshall Woods Project and shows as a net gain for all alternatives. Alternative B has the largest sediment gain, as this is the only alternative where haul would occur. BMP upgrades to Road 99/Trail 515 are necessary and will help to maintain low sediment loading from the road/trail. Lower Rattlesnake Creek WEPP modeling in the Lower Rattlesnake Creek watershed shows that larger amounts of sediment are generated from the dense network of roads (Table 5), as opposed to the Middle Rattlesnake (Table 9). Alternatives A and D reflect the implementation of the 2008 Section 31 Decision Memo and routine maintenance along the main Rattlesnake Road 515/Trail 99, which shows as a net gain for all alternatives. The differences in comparison to Alternatives B and C are the result of haul use. Again, Alternative B shows the most gain from the use of Road 515/Trail 99, which would not be used under Alternative C. However, because of the overall low amount of sediment generated from Road 515/Trail 99, there is very little difference between Alternatives B and C.

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Table 9. Marshall Woods modeled 10-year sediment budget for all road related activities.

Watershed Alternati

ve Tons/Year*

Increase from Timber Sale (per

year)

Increase from Other Activities

(per year)**

Long-term Modeled

Reduction (per year)

Tons Percentage Tons Percentage Tons Percentage

Mid

dle

Rat

tlesn

ake A, C, &

D 0.1 0 0 0.02 28 0.02 28

B 0.1 0.04 53 0 0 0.06 63

Low

er

Rat

tlesn

ake

A & D 7.1 0 0 0.4 6 0.3 4

B 7.4 0.3 4 0.4 6 0.4 6

C 7.4 0.3 4 0.4 6 0.4 6

Mar

shal

l C

reek

A 10.3 0 0 0 0 0 0 B & C 12.2 0.2 2 2.5 24 2 19

D 12.1 0 0 2.5 24 1.8 17 *Includes previously approved BMP activities on road/trail 99. **Includes Road Storage, Decommissioning, and Culvert Removals. Marshall Creek Similar to the Lower Rattlesnake Creek watershed, WEPP modeling shows that larger amounts of sediment are generated from the road network in Marshall Creek (Table 5), as opposed to the Middle Rattlesnake (Table 9). In this watershed, Alternatives B and C are the same, reflecting haul use and ‘other’ road activities, while Alternative D only shows ‘other’ road activities. All action alternatives show a net gain in sediment loading.

Twenty-four percent of the short-term sediment load modeled for ‘other’ road activities under all alternatives is from road decommissioning and Level III storage, which includes the removal of 17 culverts and the removal/replacement of 2 culverts (road to trail conversion and routine maintenance). This short-term increase of about 2.5 tons could potentially offset 250 tons of sediment if these culverts were to fail. For Alternatives B and C, haul use would result in additional short-term gains of about 2%. The post-haul sediment reduction from the application of BMPs to haul routes, combined with the potential offset for the culvert removals could more than cancel out the short-term increases in this watershed.

Road Sedimentation Summary It is anticipated that decommissioned roads would have an initial pulse of sediment followed by a long-term decrease in chronic sedimentation to stream. This was shown to be the case in a study on short-term sediment delivery from road decommissioning (Hickenbottom, 2001) conducted on the Lolo NF. Therefore, modeled sediment delivery values from decommissioning should be viewed relative to differences between

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alternatives, but always against substantive positive long-term gains once decommissioning is employed.

The proposed Marshall Woods project activities are expected to contribute to short-term sediment loading, but long-term benefits to water resources beyond the 10-year analysis window are expected from proposed road BMP upgrades, storage, and decommissioning. Design criteria and application of BMPs would ensure that water quality standards are maintained. When only considering action alternatives, Alternative D would generate the least amount of sediment within the modeled 10-year timeframe; however, when all project activities and potential offsets are considered on a watershed basis Alternatives C and D would both be considered slightly more beneficial than Alternative B.

2. Silviculture Influence Indicators

Acreage of proposed silviculture activities are equal under all action alternatives, and cover about 14% of the affected analysis area (Table 10). The levels of silviculture treatments vary in response to the issues identified during public scoping. Commercial activities would affect less than 3% and less than 2% of the analysis area, under Alternatives B and C, respectively. There are no commercial treatments proposed under Alternative D.

Table 10. Acres of proposed silviculture treatments in the Marshall Woods project area.

Treatment Alt B Alt C Alt D

Ecosystem Maintenance

Burning preceded by Understory

Slashing or Small Tree Thinning

Non-commercial Thinning and Underburning 961 961 961

Non-commercial Thinning and Handpile/Machine

Pile and Burn 314 539 945*

Subtotal Ecosystem Maintenance Burning

1275 1500 1906*

Thin and use Prescribed Fire 740 515 0 Young Stand Thinning followed by Prescribed

Fire 477 477 477

Non-commercial Thinning & Handpiling & Burning 248 248 357

Meadow/Aspen Restoration 40 40 40 Ecosystem Maintenance Burning 729 729 729 Site Preparation and Reforestation 450 450 450

Grand Total 3959 3959 3959 *=Acres in Alternative D are handpiling only, not machine piling. All proposed silvilcultural activities involve some level of prescribed burning. No aerial ignitions would be initiated within RHCA buffers but ground ignitions are allowed within 50 foot of stream channels and fire would be allowed to creep into these areas. Some tree mortality may occur within RHCA buffers. This has benefits for stream energy dissipation, sediment retention, and fish habitat. Fire may also create a short-term pulse

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of available nutrients into stream channels (Minshall et al. 1998). Nutrient mobilization in upland soils should peak after burning and decrease to background levels within two years as revegetation occurs and nutrients become locked up in plant biomass (Choromanska and Deluca 2002). None of the action alternatives would detrimentally impact water resources because of BMP and Resource Protection Measure implementation. Fine Sediment Delivery Assessment

The net sediment delivery effect of proposed silviculture activities is expected to have few, if any, impacts relative to the proposed road use changes in the project area. The modeling results indicate that most of the proposed silviculture activities causing ground disturbance occur at distances from water resources with little to no probability of sediment delivery. This is also supported by current research (Litschert and MacDonald 2009) which shows that current forest harvest procedures and BMPs are largely effective at reducing rilling and sediment sources. Water Yield

Proposed road, timber harvest, and fuel treatment activities are not expected to have detrimental effects on water yields in the analysis area. Under Alternative B, the most extensive treatment proposal, management could increase ECAs by about 4%, 7%, and 2% in the Middle Rattlesnake, Lower Rattlesnake, and Marshall Creek watersheds, respectively. Total projected ECA values are below the range of historic stand values (39%) in all analysis watersheds.

Cumulative Effects Cumulative impacts result when the effects of an action are added to or interact with other effects from past, present, or reasonably foreseeable actions in a watershed. Table 11 displays effects that were considered over a time period of at least 10-20 years. Table 11. Cumulative Effects Summary Table.

ACTION Contribution and Possible Trend Natural Events Wildfire Historically wildland fires were likely a frequent disturbance factor,

although only the Upper Rattlesnake Creek HUC (above the project area) has experienced large acreages of recent wildfire. Increases in sediment production and runoff from large fire events likely influenced water quality. Although this may lead to short-term increases in nutrient loading, sediment delivery, and water yields; wildfire is generally a desired ‘pulse’ event that positively influences water resources.

Anthropogenic Events Wildland Fire Suppression

Wildland fire suppression has likely affected water resources in relation to a possible decrease in water yield because increases in canopy cover have greater water uptake and interception. However, this is not currently negatively affecting water resources. Continued suppression could result in higher intensity wildfire, although even in high intensity scenarios, negative conditions tend to be short-term, or “pulse” in

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ACTION Contribution and Possible Trend nature, and in the long-term may be beneficial to water resources. Proposed silviculture treatments should reduce the wildfire intensity in treatment areas and should offset the effects of past suppression to some extent.

Timber Harvest Water yield increases are anticipated from proposed harvest activities; however, treatments could help return water yield to historic levels. Tree recruitment to streams has been reduced in areas where roads and thus tree removal has occurred near. Future forest trends are for increased tree recruitment as natural recovery and tree growth occurs in previously disturbed riparian areas.

Young Tree (Noncommercial) Thinning

Young tree thinning has occurred in the analysis area and is proposed. Very small increases in water yield are anticipated from proposed activities, as stands are managed to natural basal areas.

Prescribed burning

Prescribed burning has occurred in the analysis area, is reasonably foreseeable, and is also proposed. By potentially reducing the wildfire intensity in treatment areas, the effects to water resources could be a reduction in sediment loading and more natural water yields.

Road Construction, Maintenance, and Improvements

In the past, road construction has influenced water resources, as described previously. Long-term improvements would continue to occur as road improvements, such as BMPs, culvert upgrades, storage, and/or decommissioning are implemented in the project area.

Recreation A large part of the project area falls within the Rattlesnake National Recreation Area. Overall, recreation is not creating large-scale watershed impacts. There are many dispersed recreation sites along Rattlesnake Creek. These areas see localized removal of trees and sediment introductions, but effects are minor. Recreational use will continue and likely increase in the future, which may require active management to protect forest resources, especially along stream banks and lakeshores. Project proposals for BMP improvements to Road 515/Trail 99 will address some of the dispersed use along Rattlesnake Creek.

Firewood/ Misc. product gathering

Firewood gathering has occurred and will continue to occur in the future although it is not allowed in the RNRA. Effects are minor and localized. Firewood cutting in RHCAs likely occurs along roads and at dispersed camping areas.

Upper Rattlesnake Dams

Mountain Water Company holds senior water rights in the Rattlesnake watershed. Water storage is enhanced through the operation of small dams on eight lakes high in the Rattlesnake Wilderness. Mountain Water Company inspects the dams every five years. These dams are all rated as Significant and Low Hazard Potential according to the latest inspection report. The construction of the dams altered local water tables and disrupted stream/valley bottom sections where the dams were placed. Initially, the water budgets for these sites may have created deficits in tributary streamflows and possibly in Rattlesnake Creek until the dams were filled. Currently, the dams likely act to dampen the peak of runoff and help to maintain year-round streamflow in the affected tributary drainages. Use of these dams will continue to occur, and detrimental effects on

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ACTION Contribution and Possible Trend water resources are not anticipated. Routine dam inspections and maintenance are intended to prevent dam failure (which would have negative impacts on water quality).

Private Land Development

The construction of roads and buildings on private land within the analysis area will likely continue into the future, but is limited by the amount of available private lands. Building near water resources, especially within riparian areas and floodplains has likely affected and continues to affect water quality through the localized removal of sediment filtering and shade producing vegetation, and increased runoff from impervious surfaces (buildings, paved roads, etc.).

Summary The implementation of portions of two recent Decisions in the project area (Rattlesnake NRA Wildlife Habitat Improvement and Ecosystem Maintenance Burning DN 1997 and Section 31 DM 2008), as well as maintenance along Road 515/Trail 99 are reasonably foreseeable actions within the Middle and Lower Rattlesnake Creek watersheds. All of these actions have been analyzed for effects in combination with the proposed activities of the Marshall Woods project. Combined with the proposed activities of the Marshall Woods project, and with the implementation of BMPs, these projects would not be expected to have major effects on water quality within the project watersheds. Cumulatively, road density would be reduced by about 4% in the Lower Rattlesnake HUC, and by about 8% in the Marshall Creek watershed, which includes the removal of roads from water resource sensitive areas. These benefits are reasonably foreseeable in the Lower Rattlesnake because of approved actions from the 2008 Section 31 Decision Memo; however, no road improvements would occur in the Marshall Creek watershed unless an action alternative is implemented. The benefits of these actions include a decrease in long-term sediment delivery and recovery of stream, riparian, and forest functions (lasting beyond the 10-year modeled timeframe). For all action alternatives, BMP practices would be employed during road work, including storage, decommissioning, and culvert replacements to minimize potential sediment effects to water resources (e.g., slash filter windrows, temporary culverts, water diversion), as well as for all silvicultural activities. Proposed road, timber harvest, and fuel treatment activities are not expected to have negative effects on water yield in the analysis area. Total projected ECA values under the most extensive treatment alternative, Alternative B, are below historic stand values for open area conditions, as well as below current research thresholds indicating observable changes in water yield (Table 13). On a watershed basis, Alternatives C and D would be slightly more beneficial to water resources because outside of road BMP upgrades, there are no additional Management Area 13 improvements proposed under Alternative B in the Middle Rattlesnake watershed.

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Implementation of road decommissioning, level III storage, and culvert removals/upgrades would primarily occur in the Lower Rattlesnake and Marshall Creek watersheds. These activities are anticipated to benefit stream and riparian functions (e.g., sediment transport and associated habitat structures, shading, large woody debris input) in Management Area 13 and align with INFISH Riparian Goals and Management Objectives for these areas.

Consistency with Forest Plan and other Regulations Alternative A partially fulfills water resource regulatory requirements, but does not immediately work towards improving watershed conditions aside from the maintenance and BMP work that will be performed on the first 3.7 miles of the main Rattlesnake corridor Road 99/ Trail 515. All action alternatives achieve Forest Plan, INFISH, and other regulatory requirements because all management provisions, resource protection measures, and monitoring actions identified in the Project File are incorporated into the alternatives. It is not anticipated that the limits of acceptable change regarding water quality in Appendix D of the Rattlesnake National Recreation Area and Wilderness Management Direction would be exceeded for this project. Specific sections of Appendix D are addressed below: • The geometric mean number of organisms in the coliform group must not exceed 50

per 100 milliliters. The proposed activities will not have any effects on organisms in the coliform group.

• No change from natural pH is allowed. No change in pH from the proposed activities is anticipated.

• No increase above naturally occurring turbidity is allowed. Although minor increases in sediment delivery (from modelling) may occur, this is not anticipated to cause turbidity levels to be above those that occur naturally from disturbances such as wildfires and streambank scour.

• No increase above naturally occurring water temperature is allowed. There are no anticipated increases in water temperature from the proposed activities. Stream riparian buffers would be utilized to maintain adequate stream shading.

• No increases are allowed above naturally occurring concentrations of sediment, settleable solids, oils, or floating solids, which will or are likely to create a nuisance or render the waters harmful, detrimental, or injurious to public health, recreation, safety, welfare, livestock, wild animals, birds, fish, or other wildlife. Although minor increases in sediment delivery (from modelling) may occur, this is not anticipated to be above those that occur naturally from disturbances such as wildfires and streambank scour.

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• No increase in true color is allowed. There are no anticipated increases in true color.

• No increases in toxic or other deleterious substances, pesticides, and organic and inorganic materials including heavy metals, above naturally occurring concentrations, are allowed. This is not anticipated to occur.

• No increases in radioactivity above natural background levels in allowed. There are no anticipated increases in radioactivity.

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References Belt G. H., J. O' Laughlin and T. Merrill. 1992. Design of Forest Riparian Buffer Strips

for the Protection of Water Quality: Analysis of Scientific Literature. Idaho Forest, Wildlife and Range Policy Analysis Group, Report No.8, Idaho Forest, Wildlife, and Range Experiment Station, University of Idaho.

Burton, T.A. 1997. Effects of basin-scale timber harvest on water yield and peak streamflow. Journal of the American Water Resources Association, v.33, no. 6, pp.1187-1196.

Casselli, J., B. Riggers, and A. Rosquist. 1999. Siegel Creek Culvert Removal Water Monitoring Report. Lolo National Forest, Missoula, MT.

Choromanska, U. and T.H. DeLuca. 2002. Microbial activity and nitrogen mineralization in forest mineral soils following heating: evaluation of post-fire effects. Soil Biology and Biochemistry 34: 263-271.

Elliot, W.J. and Audin, L.J. (Eds.). 2010. Cumulative Watershed Effects of Fuel Management in the Western United States. [Online]. Available: http://forest.moscowfsl.wsu.edu/engr/cwe/

Elliot, W.J. 2005 DRAFT Chapter for a General Technical Report on the Environmental Consequences Toolkit for Applied Wildland Fire Research in Support of Project Level Hazardous Fuels Planning. [Online]. Available: http://forest.moscowfsl.wsu.edu/fswepp/docs/fume/WEPP_FuME.pdf

Elliot, W.J., D.E. Hall, D.L. Scheele. 1999. WEPP: Road (Draft 12/1999), WEPP Interface for Predicting Forest Road Runoff, Erosion, and Sediment Delivery. USDA, Forest Service, Rocky Mountain Research Station, Technology and Development Program. San Dimas, CA. http://forest.moscowfsl.wsu.edu/cgi-bin/fswepp/wr/wepproad.pl http://forest.moscowfsl.wsu.edu/fswepp/docs/wepproaddoc.html

Ercelawn, A. 1999. End of The road. The adverse ecological impacts of roads and logging: A compilation of independently reviewed research. Published by the Natural Resources Defense Council, San Francisco, CA

Executive Order 11988, Floodplain Management, 1977. http://www.archives.gov/federal-register/executive-orders/1977-carter.html

Executive Order 11990, Protection of Wetlands, 1977. http://www.archives.gov/federal-register/executive-orders/1977-carter.html

Federal Water Pollution Control Act of 1972 (Public Law 92-500) as amended in 1977 (Public Law 95-217) and 1987 (Public Law 100-4). http://www.epa.gov/region5/water/cwa.htm. Also known as the Clean Water Act.

Frissell, C. 1996. Healing the watershed: A guide to the restoration of watersheds and native fish in the west. Pacific Rivers Council, 2nd Edition, Chp. 1.

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Furniss, M. J., S. A. Flanangan, and B. McFadin. 2000. Hydrologically Connected Roads: An Indicator of the Influence of Roads on Chronic Sedimentation, Surface Water Hydrology, and Exposure to Toxic Chemicals. Stream Notes, U.S. Forest Service, Rocky Mountain Research Station, Fort Collins, Colorado, USA.

Grant, G.E., S.L. Lewis, F.J. Swanson, J.H. Cissel, and J.J. McDonnell. 2008. Effects of Forest Practices on Peak Flows and Consequent Channel Response: A State-of-Science Report for Western Oregon and Washington. USDA Forest Service, Pacific Northwest Research Station, General Technical Report PNW-GTR-760.

Hickenbottom, J.A.S. 2001. A comparative analysis of surface erosion and water runoff from existing and recontoured Forest Service roads: O’Brien Creek Watershed, Lolo National Forest, Montana, USA. Master’s Thesis Abstract.

Litschert, S.E., and L.H. MacDonald. 2009. Frequency and characteristics of Sediment Delivery Pathways from Forest Harvest Units to Streams. Forest Ecology and Management. Draft copy.

Losensky, B.J. 1993 (in draft). Historical vegetation in Region One by climatic area. On file at Lolo National Forest, Fire Management Office, Missoula, MT.

Luce, C.H. and B.C. Wemple. 2001. Introduction to special issues on hydrologic and geomorphic effects of forest roads. Earth Surface Processes and Landforms 26, 111-113.

MacDonald, L.H. and J.D. Stednick. 2003. Forests and water: A state-of-the-art review for Colorado. Colorado Water Resources Research Institute, CSU, Fort Collins, CO. pp21-29. At http://welcome.warnercnr.colostate.edu/~leemac/publications.htm.

McCaffery, M., T.A. Switalski, and L. Eby. 2007. Effects of road decommissioning on stream habitat characteristics in the South Fork Flathead River, Montana. Transactions of the American Fisheries Society 136:553-561.

Minshall, G.W., C.T. Robinson, and T.V. Royer. 1998. Stream Ecosystem responses to the 1988 Wildfires. Yellowstone Science. Summer 1998.

Montana Department of Environmental Quality, 2010. State of Montana 2010 Integrated 303(d)/305(b) Water Quality Report. http://cwaic.mt.gov/

Montana Natural Heritage Program, 2010. National Wetlands Inventory (NWI) for Montana. http://nris.mt.gov/nsdi/nris/shape/nwi_poly.zip

Natural Resources Conservation Service, 2011. National Water & Climate Center Temperature and Precipitation Summary for Missoula County, 1971 to 2000. http://www.wcc.nrcs.usda.gov/ftpref/support/climate/taps/mt/30063.txt

Pfankuch, D. 1973. Vegetation manipulation guidelines for the Lolo National Forest; a revision and updating of the October 1967 procedures. USDA Forest Service. Lolo National Forest. April, 1973. 69 p.

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Riggers, B., D. Kramer, S. Henderickson, A. Rosquist, T. Stylte, and K. Cikanek. 1998. Lolo National Forest modified bull trout matrix: rationale used in evaluating baseline conditions. 1998.

Rosgen, D.L. 1996. Applied River Morphology. Wildland Hydrology, Pagosa Springs, Colorado.

Taylor, S.E., Rummer, R.B., Yoo, K.H., Welch R.A., Thompson J.D. 1999. What we know—and don’t know—about water quality at stream crossings. Journal of Forestry. 97(8): 12-17.

US Army Corps of Engineers, Waterways Experiment Station. 1987. Corps of Engineers Wetlands Delineation Manual. Wetlands Research Program Technical Report Y-87-1.

USDA Forest Service. 1986. The Lolo National Forest Plan. USDA Forest Service,

Lolo National Forest, February 1986. Missoula, MT. http://www.fs.fed.us/r1/wmpz/documents/existing-forest-plans.shtml

USDA Forest Service. 1988. Forest Service Handbook 2509.22 - Soil and Water

Conservation Practices Handbook, R-1/R-4 Amendment No. 1, May 1988. Missoula, MT and Ogden, UT.

USDA Forest Service. 1990. Forest Service Manual; Series 2000, National Forest Resource Management; Section 2500, Watershed and Air Management; Chapter 2530, Water Resource Management, (Amended 1990); Sections 2532.02, 2532.03. http://fsweb.wo.fs.fed.us/directives/html/fsm2000.shtml

USDA Forest Service. 1995. Decision notice and finding of no significant impact for the inland native fish strategy (INFISH). USDA Forest Service, Northern, Intermountain, and Pacific Northwest regions, Inland Native Fish Strategy, Idaho Panhandle National Forests, 3815 Schrieber Way, Coeur d’Alene, Idaho 83814.

USDA Forest Service. 1996. Quigley, T.M., Haynes, R.W., and Graham, R.T., tech eds.

1996. Integrated scientific assessment for ecosystem management in the interior Columbia Basin and portions of the Klamath and Great Basins, PNW Research Station.

USDA Forest Service, 2000. Water/Road Interaction Technology Series. Technology and Development Program. San Dimas Technology and Development Center. San Dimas, CA.

USDA Forest Service. 2002. Lolo National Forest. Best management practices effectiveness monitoring report. 117pp. http://www.fs.fed.us/r1/lolo/resources-natural/index-best-mgt-prac.shtml

U.S. Geological Survey and U.S. Department of Agriculture, Natural Resource Conservation

Service. 2009. Federal Guidelines, Requirements, and Procedures for the National Watershed Boundary Dataset: U.S. Geological Survey Techniques and Methods 11-A3, 55p.

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U.S. Geological Survey, 2011. Montana Flood-Frequency and Basin-Characteristic Data. http://mt.water.usgs.gov/freq?page_type=table

Wemple, B.C. and J.A. Jones. 2003. Runoff production on forest roads in a steep,

mountain catchment. Water Resources Research 39(8), 1220, doi:10.1029/2002WR001744, 2003.

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Appendix A - BMP Effectiveness and Performance Criteria Effectiveness of Best Management Practices and resource protection measures have been investigated in research studies and monitored by the Lolo NF as well as by the State of Montana. These studies and evaluations demonstrate that BMPs and resource protection measures can be successful at preventing erosion and sedimentation and have been implemented by the Lolo NF specifically as well as by the US Forest Service in Montana. Results of these studies and evaluations are summarized below. Lolo NF BMP Monitoring Results The Lolo NF has evaluated the implementation and effectiveness of BMPs in a number of case studies. The evaluation results demonstrate that these measures are effective at reducing sediment impacts that might otherwise occur without the use of BMPs (USDA 2002). Several of the case study evaluations were for the Northside Timber Sale and reflect the BMP effectiveness likely to be achieved for proposed activities of the Marshall Woods Project (Numbers denote FSH 2509.22 practices, USDA 1988.) Effective BMP implementation evaluated in the Northside Timber Sale include: Re-vegetation of Surface Disturbed Areas (13.04), Using Sale Area Maps to Designate Soil and Water Protection Needs (14.03), Protection of Unstable Areas (14.05), Log Landing Erosion Prevention and Control (14.11), Erosion Prevention and Control Measures during Timber Sale Operations (14.12). Results of other BMP evaluations across the Lolo NF further demonstrate the effectiveness of BMPs on protecting soil and water resources. Montana DNRC 2010 BMP Audit Results The Forest Service has cooperated with Montana DNRC and other land managers to monitor the implementation and effectiveness of Forestry BMPs of recent forest management activities. This effort is known as BMP auditing and results are provided in an annual report. As an example, for implementation auditing in 2010, 96% out of 554 Federal practices evaluated application met or exceeded Montana Forestry BMP standards (DNRC 2010). Federal practices evaluated in 2010 consisted of 14 Forest Service sites, two of which were located on the Lolo NF. Of the 554 practices evaluated, 3% of the applications rated as minor departures, 1% was rated as a major departure, and 0% rated as gross neglect. Across all ownerships (DNRC, Federal, Industrial and Non-industrial/Private), BMP applications were met or exceeded 97% out of 1,469 evaluated practices, 2% rated as minor departures, less than 1% rated as major departures, and 0% rated as gross neglect. In 2010 effectiveness auditing, out of 554 Federal practices rated, 97% provided adequate protection, <1% had minor/temporary impacts, 2% had major/temporary/prolonged impacts, and <1% had major/prolonged impacts. Across all ownerships, 98% of practices

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provided effective protections, <1% had minor/temporary impacts, 1% had major/temporary/prolonged impacts, and <1% had major/prolonged impacts. To provide easy reference and support to statements made herein, Table A-1 below provides summary of some findings provided within the Lolo Timber and Road Practices Best Management Practices (BMP) Report (refer to cited references and Appendix D of the Lolo NF Forest Plan for a comprehensive review of BMP effectiveness). A-1. Examples of BMP Effectiveness Monitoring Findings Designed/Required

BMP Practice Effectiveness Monitoring Results

Coarse Woody Debris Requirements in Units

Leaving coarse woody debris to reduce surface erosion and protect long-term site productivity: no signs of surface erosion on a unit meeting CWD guidelines (Lolo BMP 14.24). As cited in Seyedbagheri 1996, Meeuwig (1971) found that surface cover was the most important predictor for erosion during simulated high-intensity rain events, and the effect increased as slope steepness increased.

Landing and Skid Trail Requirements

Operations and rehabilitation of landings and skid trails: the Lolo BMP report (USDA-Forest Service, 2002) evaluated the effectiveness of Lolo BMPs 14.11 (Log landing erosion prevention and control), 14.12 (Erosion prevention and control measures during timber sale harvest), and 14.15 (Erosion control on skid trails). All measures were found to be effective in preventing erosion on skid trails and landings. Seyedbagheri (1996) summarized literature that found water bars (especially log water bars) to be highly effective in diverting water: on a scale of 1.0 (completely effective) to 4.8 (completely ineffective), log water bars rated 1.78 on granitic soils and 1.54 on basaltic soils, compared to 2.15 (granitic) and 2.25 (basaltic) for slash dams, and 2.93 (granitic) and 1.60 (basaltic) for lopping and scattering of slash (Kidd 1963). In another study, seeded skid trails with slash barriers or cross ditches generally contained erosion during the first 4 years, after which skid trails had stabilized (Haupt and Kidd 1965). McGreer (1981) determined that, where ash layers had been removed from skid trails, placing slash on a 50% gradient skid trail resulted in 98.5% less erosion than on a 40% gradient skid trail without slash, and 94.7% less than a 15% gradient skid trail without slash. Scarifying of compacted areas (skid trails in the reference cited—Froehlich et al. 1985) was found to be effective due to persistence of compaction (more than 25 years) on some soils.

Required seasonal and operation restrictions

Seasonal restrictions on ground-based logging activities: Lolo NF monitoring on a unit of the Cave Helo Timber Sale determined that winter logging over snow (there was more than two feet on the ground) was effective in protecting soil resources (Lolo BMPs 14.04 and 15.04).

Required slope limitations for tractor operations

Slope limitations for tractor operations: as cited in Seyedbagheri, data from McGreer (1981) comparing erosion rates on skid trails that were on 15% gradients with those on 40-45% grades show higher erosion rates on the steeper slopes in all instances, especially where subsoils were exposed. Ground skidding also disturbs a greater area than cable systems, including skyline (Megahan 1980). The Lolo NF monitored the

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effectiveness of limiting slopes for tractor operations, and found that limiting slope steepness for tractor operations greatly reduced the risk of sediment production from skid trails (Lolo BMP 13.02). They also acknowledged that a 10-12 inch layer of snow helped protect soils and helped maintain litter layers.

Required road improvement practices (BMPs)

BMP installation on roads: Burroughs and King (1989) describe the effectiveness of numerous erosion control measures for roads, including surfacing, establishing ground cover on fillslopes, ditch treatments, etc.

Proper culvert sizing and placement, relocating roads, limiting road gradients, and performing a variety of site-appropriate BMPs can markedly reduce adverse erosion and sediment delivery impacts. Effects are also offset by implementation of variety of mitigation measures that provide specific effectiveness values of selected measures in reducing erosion. Table A-2: Effectiveness of selected erosion control measures (Seyedbagheri 1996) Measure Effectiveness /reduction in erosion Straw mulch 32-47% reduction in erosion Dense (grass) cover 99.5% reduction in erosion Filter windrows 87-99% retention of eroded material Hydromulch, seed, fertilize 71% effectiveness Straw, crimp, netting 93% effectiveness Excelsior mats 75% on 1:1 cutslopes, 60% on 0.75:1 cutslopes Additional examples of erosion reduction from selected road treatments are shown below in Table A-3 (from Burroughs 1990; Burroughs and King 1989): Table A-3: Additional erosion control effectiveness (Burroughs 1990; Burroughs

and King 1989)

Measure Effectiveness Seasonal road closure when roads are wet Reduces rutting; trials showed ruts increase

sediment production by 2.1 times over an unrutted road.

Surfacing (trials used a 4-inch layer of 1.5-inch minus rock). Need at least 4 inches of gravel for notable decrease in sediment production.

Reduction in sediment production by 79% compared to unsurfaced condition. 6” of 1.5-inch minus gravel reduced sediment production by 70-92%, in several studies.

Erosion mats on cutslopes Sediment reduction of 95% on 1:1 slopes (gneiss and schist parent material)

Actual effectiveness depends on site conditions and implementation methods. Both Burroughs (1990) and Burroughs and King (1989) stress the need to install protection measures as soon as possible after construction since most material is eroded in the first few years after construction. About half of the total fillslope sediment production measured over two years in one study took place in the first summer and fall after

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construction. Therefore, measures that are put in place immediately after construction have a greater chance of reducing sediment production than measures that are installed later. Reducing the amount of displaced material that actually reaches stream channels is the second important aspect of reducing sediment delivery from roads, after reducing erosion. As cited in Seyedbagheri (1996), Haupt (1959) found that “slope obstruction index” (indicator of amount of logs, vegetation, etc. on slopes below roads that would slow surface runoff) was the variable most highly correlated with sediment transport distance (p.41 in Seyedbagheri 1996). Other authors also acknowledge the importance of slope obstructions in reducing sediment transport distances (Ketcheson and Megahan 1996).

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