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Blackjack Creek Mitigation Site

Restoration and Management Plan

Wildlands of Washington, Inc.

June 2006

Note from the author:

This document was prepared for Wildlands of Washington, Inc., a mitigation banking

company based in western Washington State.

Preparation included:

• Site research into the existing site conditions (soils, vegetation, topography);

• Preparation of the proposed mitigation design;

• Close communication with the client to properly capture project intent;

• Several iterations of draft submittals and incorporation of revisions based on client

comments;

• Preparation of supporting tables (figures and appendices provided by others); and

• Finalization of document for submittal to state and federal agencies (e.g. U.S.

Army Corps of Engineers, WA Department of Ecology).

Because of this document’s proprietary nature, the full table of contents is shown, but only

select sections are provided.

Janice Cessna

June 16, 2006 Blackjack Creek Mitigation Site

Wildlands of Washington, Inc. Restoration and Management Plan

1

Table of Contents

Executive Summary …………………………………………………………………………………...3

Project Purpose…………………………………………………………………………………………4

Mitigation Approach…………………………………………………………………………………...4

Mitigation Site Goals and Objectives……………………………………………………………...5

Mitigation Site Description……………………………………………………………………………5

Site Details ………………………………………………………………………………………….5

Site Selection Rationale …………………………………………………………………………...6

Constraints of the Site ……………………………………………………………………………..5

Existing/Baseline Conditions …………………………………………………………………….6

Site Plan and Design ………………………………………………………………………………...11

Description ………………………………………………………………………………………….5

Water Regime ………………………………………………………………………………………6

Grading Plans ……………………………………………………………………………………...5

Planting Plans ……………………………………………………………………………………...6

Wetland Functions Comparison………………………………………………………………….4

Mitigation Acreages and Perimeter Buffer ……………………………………………………5

Performance Standards ……………………………………………………………………………..15

Monitoring Plan ……………………………………………………………………………………...18

Monitoring Schedule……………………………………………………………………………...18

Monitoring Methods………………………………………………………………………………20

Maintenance, Monitoring and Contingency Plans ……………………………………………..21

Financial Assurances and Site Protection………………………………………………………..21

References ……………………………………………………………………………………………..22



2

List of Tables Table 1 – Proposed Mitigation Acreage without Perimeter Buffer ……………………………XX

Table 2 – Proposed Mitigation Acreage with Perimeter Buffer ……………………………....XX

Table 3 – Monitoring Schedule for Blackjack Creek Mitigation Site ………………………….19

List of Figures Figure 1 - Vicinity Map

Figure 2 - Site Overview Map

Figure 3 – Zoning Map

Figure 4 - Wetland Delineation

Figure 5 - Groundwater Well Locations

Figure 6 - Natural Resource Conservation Service Soils

Figure 7 - FEMA Floodplains

List of Appendices

Appendix A – Existing Conditions map

Appendix B – Cultural Resources Report by Landau Associates

Appendix C – Phase I Environmental Site Assessment by Landau Associates

Appendix D – Wetland Delineation Report by Landau Associates

Appendix E – Blackjack Creek Mitigation Site groundwater data

Appendix F – Grading Plan, Planting Plan, and Details sheets

Appendix G – Wetland Rating Form: Blackjack Creek Mitigation Site After Implementation



3

Water Regime The proposed Mitigation Site will experience the same flooding frequency and duration that

occurs now. Groundwater will remain the primary year-round water source with surface flow

from Blackjack Creek contributing a significant portion only in the winter season. Therefore, no

water rights are needed. No mass grading, culvert installation, or water control structures are

proposed in the project design.

As described earlier in the existing conditions, the dredged creek spoils currently serve as a

physical barrier to initial floodwaters within Blackjack Creek. By removing the spoils, the creek

will have an entirely open connection to its floodplain within the project site. Some spoils,

however, will be left in place as upland islands for greater habitat diversity. These will be

approximately twenty-five square feet (approx. 5’ by 5’) or less and scattered intermittently

along the creek length with approximately several hundred feet between each.

Removal of drain tiles and plugging of drainage ditches will restore the natural hydrologic cycle

within the site by discontinuing the current expedited drainage routes. The groundwater table

will likely rise closer to the ground surface, becoming more readily available throughout the year

and sustaining a saturated perennial wetland system. Existing herbaceous species dominated by

facultative grasses will transition to domination by obligate sedges and rushes.

Because no volume or flow analysis has been conducted on Blackjack Creek, a quantification of

the potential water table rise is not presented. However, the review of the existing conditions

within the southeast forested wetland as discussed earlier in the existing conditions section offers

a glimpse of the future habitat. In this area, saturation is at or within a few inches of the ground

surface year-round, as demonstrated in Landau Associates’ wetland delineation report.

Additionally, small pockets of water ponds in low spots during the winter months.

The groundwater monitoring wells will be kept in place and maintained during the

implementation of this Restoration and Management Plan, as well as through the duration of the

monitoring and maintenance periods. The wells will likely be preserved and occasionally

monitored for a time after final project acceptance by responsible agencies.

Grading Plans

Proposed grading will be limited to the removal existing spoils along Blackjack Creek and

removal of the existing site access road east of the creek bridge. Both areas will supply fill

material for use on-site as ditch plugs and upland hummocks. This process involves

approximately 2000 cubic yards of material. Because the volume of available spoil material will

not be sufficient to facilitate filling of all on-site ditches, plugs will only be placed at key

intersections with Blackjack Creek, thereby blocking site drainage and impounding water within

the site interior. However, the southwest ditch and the long perimeter ditch running along the

south and east boundary, will remain intact since impacting their function would have significant

impacts to neighboring properties. In the future, should Wildlands succeed in acquiring the

adjacent parcels, these ditches will be abandoned.



4

Remaining spoil material will be used to create hummocks of varying dimensions across the

rehabilitated wetland. Proposed locations and approximate dimensions are depicted on the

Grading Plan and Details (Appendix F). Also depicted is the removal of all culverts and concrete

slab bridges. The existing bridge crossing Blackjack Creek will remain for site access purposes.

All extracted items will be disposed of offsite. No major invasive vegetation removal is planned

during construction. Any incidental invasive species material removed during project

implementation will be removed from the site.

After the grading and demolition work is completed, removal of the drain tiles will occur.

Unfortunately, the tile’s precise locations are not known. In order to find and successfully

remove these, a small dozer or similar machine with ripping tines will make passes parallel to

Blackjack Creek on both sides. No equipment or surface disturbance will occur within ten feet of

the top of bank.

Focusing the ripping area to this vicinity will limit large-scale disturbance to the site by limiting

the ripping to an area already disturbed by grading activities. While the tiles will remain across

the remaining Mitigation Site, their function will be halted through this localized disruption and

removal. Any tiles brought to the surface will be collected and disposed offsite.

Planting Plans

Care will be taken during implementation of the grading plan elements to minimize existing

vegetation disturbance. There will be no or very limited impacts to existing scrub-shrub or

forested communities. However, disturbance to herbaceous vegetation will occur during the spoil

relocation described above. Any healthy wetland herbaceous species that can be reasonably

salvaged will be removed from the excavation area and either returned after grading is complete,

or transplanted to a similarly disturbed location elsewhere on site.

Aside from replacing salvaged material, Wildlands will also plant native species that are known

to occur in the area and are appropriate for the site. Herbaceous emergent wetland and grass

species will be installed for immediate post-construction erosion control and wetland habitat

while woody vegetation matures. Species include Slough sedge (Carex obnupta), Tufted

hairgrass (Deschampsia caespitosa), and Scirpus lacustris (Softstem bulrush).

As for woody species, the existing scrub-shrub and forested wetland communities on site and

within the surrounding landscape indicates a mosaic of similar vegetation would be appropriate.

Existing topography and groundwater have created wetter areas in the middle and north areas of

the site. These will be planted with a scrub-shrub community dominated by Sweet gale (Myrica

gale), Western bog laurel (Kalmia macrophylla), and Labrador tea (Ledum groenlandicum).

Other species include Willow (Salix spp.), Salal (Gaultheria shallon), False azalea (Menziesia

ferruginea), and Swamp rose (Rosa pisocarpa). Shrub species will be installed at a density of

500 stems per acre.

The drier areas, primarily to the south and southeast, will be vegetated with a Western redcedar

(Thuja plicata) and Western hemlock (Tsuga heterophylla) dominated community. It will be

planted at 500 stems per acre including 275 trees and 225 shrubs per acre.



5

This community will also be planted on the hummocks scattered within the scrub-shrub area,

however, fewer shrub species will be included. The total density planted per acre will also be

500, but the amount of trees and shrubs will be 305 and 195 per acre, respectively.

Vegetation sources will vary depending upon vegetation type. Herbaceous emergent and grass

species will be installed using seed. Woody vegetation will be container stock, bare root, and/or

live stakes. Choice of plant material type and size will depend upon availability of plant material

at the time of implementation. However, plant sizes for the container stock will be restricted to a

combination of four-inch pots/tree tubes and one-gallon containers. Live stake installation will

be limited to willow and cottonwood species, with the majority installed along Blackjack Creek’s

banks.

The Planting Plan with planting and seeding schedules can be reviewed in Appendix F. A

general use seed mix will be applied on all areas disturbed by grading at rate of 40 pounds/acre.

Harrowing or roughing of the seeding surface after installation will be done to limit predation by

fauna. At least some natural recruitment is expected from existing alder, cottonwood, and willow

species on the site. Volunteers have been accounted for in the Performance Standard section

below. No irrigation or soil amendments will be installed or utilized; during years of normal

precipitation, reliance on existing groundwater will be sufficient for vegetation establishment.

The perimeter buffer around the Mitigation Site boundary will receive the same rehabilitation

and enhancement actions as the interior mitigation area including vegetation with the same

species and densities. As-built plans documenting post-construction site conditions will be

submitted to the reviewing agency in January 2008. These plans will document grading, planting,

seeding, and any other implementation requirements per the approved Restoration and

Management Plan.

Wetland Functions Comparison As part of Landau Associates wetland delineation (Appendix D), a rating was completed on the

Mitigation Site’s existing wetland complex. This included all forested, scrub-shrub, and

emergent components of the site’s wetland. The Depressional and Flat Wetland section of the

Washington State Wetlands Rating System for Western Washington (Ecology 2004) was used to

quantify the wetland functions. Overall, it rated as a Category III with a total of 44 points.

Landau explains this score is influenced not only by intensive cattle grazing on and off-site, but

also by low vegetation structure and community interspersion.

Similarly, a wetland rating was completed on the proposed Mitigation Site’s rehabilitated and

enhanced wetland complex at the end of its 5-year implementation and monitoring schedule as

outlined in later sections. This assumes that the entire site will be constructed as a whole, which

may or may not occur depending on mitigation needs within the Blackjack Creek area.

The same Depressional and Flat Wetland rating section was utilized, although the HGM Class is

slightly different. With the restored floodplain connectivity and hydrologic processes from the

proposed removal of existing creek side spoils, HGM becomes a Depressional with Riverine



6

versus the original simple Depressional class. Regardless of the slight change, the Mitigation Site

was rated as whole wetland complex using the Depressional and Flat Wetland section. A copy of

the wetland rating worksheets can be found in Appendix G. The proposed complex rated as a

Category II with a total of 69 points.

Monitoring Plan Monitoring Schedule A combination of formal and informal monitoring of the proposed compensation site will occur

through the fifth year following construction (Year 5) of each individual compensatory

mitigation area. Informal monitoring will occur periodically to document changes in the site

over time and to provide information to the natural resource entity responsible for long-term site

management. Formal monitoring will occur in Years 1 and 3 while informal monitoring may

occur periodically every year. Informal monitoring will occur in addition to formal monitoring

in some years. More frequent informal monitoring may be warranted because of specific site

conditions or site-specific goals. For example, greater frequency may be necessary to track the

re-colonization of invasive weeds or report results from management treatments that are needed.

The site will be monitored according to the schedule listed in Table 3.

Table 1. Monitoring Schedule for Individual Mitigation Cells (author’s note – abbreviated for client confidentiality)

Objective Measurement Year(s) When

Measured

1A. Grading and Hydroperiod

1 -4 . As-built topographic survey to confirm construction meets approved plans.

Year 0 December

5. Quantify area of wetlands with inundation or saturation to the surface.

Year 1 April-July

6. Conduct a jurisdictional wetland delineation. Year 5 April-July

1B. Wetland vegetation

1-2. As-built plans and photo documentation to confirm vegetation installation meets approved plan.

Year 0 December

3. Demonstrate consistent germination and growth of emergent seed in graded areas.

Year 1 April-July

4. Establish permanent transects and plots in each habitat type (3-foot radius plots for herbaceous species).

Years 3 and 5

April-July

5. Collect data on species richness and diversity per plot and extrapolate to a per acre estimate.

4A. Non-native Vegetation

1. Create species inventory map to document baseline conditions.

Year 0 April-July

2. As-built plan to confirm that existing invasive vegetation removal meets approved plan

Year 0 December

3-4. Document and minimize invasive species re-colonization.

Years 2, 3, and 5

April-July

5. Continue zero tolerance of specified species through annual inventory and eradication.

Year 2, 3, and 5

April-July



7

Monitoring Methods Formal Monitoring

Formal monitoring addresses the site’s fulfillment of project goals, objectives, and performance

standards. It may include qualitative and/or quantitative monitoring that is summarized in a

monitoring report and submitted to signatories. Formal monitoring will be conducted during

years specified in the performance standards and monitoring schedule.

Informal Monitoring

In contrast to formal monitoring, informal monitoring is intended to provide a general overview

of site progress. A qualitative visual inspection of the mitigation area will be conducted during

periodic site visits to identify concerns associated with meeting project goals and objectives.

Informal monitoring will include observation notes, site photos, etc. Informal monitoring may

also quantitatively address some performance standards of coming years, but may be less

statistically rigorous than formal monitoring. Informal monitoring will be the only monitoring

method during years for which there are no performance standards, although it will also be

employed during years of formal monitoring.

Monitoring Report Submittals

Monitoring reports for each individual compensatory mitigation site will provide a description of

site conditions observed during the past year. Reports will also include results from formal and

informal monitoring, along with a discussion of site conditions as they relate to the performance

standards. Results of monitoring will lead to recommendations for any maintenance and

contingency actions that may be necessary to ensure that the objectives and goals of the

Blackjack Creek Mitigation Site are met. Monitoring reports will be submitted to signatories in

years specified in the performance standards.

Grading Monitoring Methods

Observation of excavation and geomorphology of all created wetlands will occur during

construction to ensure establishment of desired contours. Post-construction conditions will be

documented with photographs, field notes, and as-built plans. Excavation of soil and

establishment of emergent wetland contours will occur during site construction to lower the

ground surface and introduce natural groundwater hydrology. Both as-built plans and

photographs documenting post-construction conditions will be submitted to the responsible

reviewing agency.

Hydroperiod Monitoring Methods

A wetland delineation of the Blackjack Creek Mitigation Site will be conducted per the

performance standards to provide documentation of wetland acreage. The wetland delineation

will be performed using the 1987 Wetland Delineation Manual (Environmental Laboratory

1987). Data collection and reports will be created in the same format as the existing data. The

results, including a wetland boundary map with data points and acreages, will be included with

the scheduled monitoring report submittal.



8

References Cowardin, L.M., V. Cargter, F.C. Golet, and E.T. LaRoe. 1979. Classification of Wetlands and

Deepwater Habitats of the United States. U.S. Fish and Wildlife Service. FWS/OBS

79/31.

Environmental Laboratory. 1987. U.S. Army Corps of Engineers Wetland Delineation Manual,

Technical Report Y-87-1. U.S. Army Corps of Engineers Waterways Experiment Station.

Vicksburg, Mississippi.

ESRI website. 2006. Online Hazard Maps. Environmental Systems Research Institute. Redlands,

California. URL: http://www.esri.com/hazards/index.html. Accessed on May 12, 2006.

Hruby, Granger, and Teachout. 1999. Methods for Assessing Wetland Functions, Volumes 1 & 2.

Washington State Department of Ecology. Olympia, Washington.

Hruby, T. 2004. Washington State wetland rating system for western Washington – Revised.

Washington State Department of Ecology Publication #04-06-025. Olympia, WA.

Kitsap County website. December 2005. Ordinance Regarding Growth management, Revisions

to Title 19 (Critical Areas). Kitsap County Board of Commissioners. Port Orchard,

Washington.

NRCS website. 2001. Hydric Soils List, Kitsap County Area, Washington. URL:

http://www.wa.nrcs.usda.gov/technical/soils/hydric_lists/hydosoil-wa-635.pdf. U.S.

Department of Agriculture, Natural Resources Conservation Service. Accessed on May

10, 2006.

StreamNet website. 1998. StreamNet Database (Version 98.3). Portland (OR) : StreamNet, April

1998. URL: <http://www.streamnet.org/accesstable.html>. Accessed on May 12, 2006.

Washington State Department of Ecology; U.S. Army Corpos of Engineers, Seattle District, and

Environmental Protection Agency, Region 10. March 2006. Wetland Mitigation in

Washington State – Part 1: Agency Policies and Guidance (Version1). Washington State

Department of Ecology Publication #06-06-011a. Olympia, Washington.

Washington State Department of Ecology; U.S. Army Corpos of Engineers, Seattle District, and

Environmental Protection Agency, Region 10. March 2006. Wetland Mitigation in

Washington State - Part 2: Developing Mitigation Plans (Version1). Washington State

Department of Ecology Publication #06-06-11b. Olympia, Washington.

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