CE Project Proposal

Project Name: Marx Creek Habitat Enhancement

Project Leader: Will Young

Categorical Exclusion ID: 1909.15.31.2(7) – Modification or maintenance of stream or lake aquatic habitat improvement structures using native materials or normal practices.

Geographic Location: Marx Creek, near Hyder, Alaska.

LUDs in Project Area: SV – Scenic Viewshed

General Vicinity Description: Hyder, AK, Township 68 South, Range 99 East, Section 14, Copper River Meridian.

Purpose and Need: Purpose—the purpose of this project is to improve existing spawning and rearing conditions for chum and coho salmon in the upper sections of Marx Creek. The objectives of the activities are to raise water temperature, create shallow water habitat, and ultimately increase the number of chum and coho salmon produced by Marx Creek. The project additionally provides habitat and enhancement of existing habitat for riparian dependent wildlife species through revegetation efforts. Essentially, this is a refinement of work completed during the Marx Creek Phase II (2009) and Marx Creek Channel Improvement (2010) projects.

Need—the need to improve existing habitat condition derives from a combination of low water temperatures, lack of habitat complexity, and low usage of the spawning channel by spawning or rearing salmon. There is also a need to mitigate effects to wetlands caused by transportation improvement and construction activities in the lower Salmon River.

Please see the following pages for more detailed project description including vicinity map and background information.

Summary of Activities: New Wetland Pond Complex Creation = 2.8 acres (1.9 North Pond, 0.9 South Pond)

504 feet of slew channel construction connecting 7.3 acres of existing wetlands

4.5 acres of thinning (3.5 around the North Pond, 1 acre around the South Pond) to increase solar input

1.8 acres of spawning channel stream bank rehabilitation including revegetation

Reopening 5,750 feet of existing temporary access road, decommissioned upon completion

Up to 11,733 square yards of spawning gravel fines reduction

Hand plant locally obtained vegetation along the margins of the stream channel.

Time and Duration of Activity: The work will occur during the summer of 2013. Construction activities are subject to fish timing windows and would be determined per the Title 16 MOU with Alaska Department of Fish and Game-Habitat Division.

Background and Project Area Maps This project serves as wetland mitigation for Alaska Department of Transportation (ADOT) projects

which paved a portion of the Salmon River road and reconstructed the causeway. ADOT approached

KMRD with a request for suggestions to mitigate wetland impacts. KMRD provided several ideas and

assisted ADOT in preparing a wetland mitigation plan. The plan was approved by the Army Corps of

Engineers. ADOT and the Tongass NF entered into a Memorandum of Agreement (MOA). The MOA

transferred $83,000 from ADOT to TNF, and included language obligating TNF to utilize these funds to

implement no less than 1.25 acres of wetland mitigation in the form of habitat enhancement along the

upper reaches of Marx Creek. This work must be completed by December 31, 2013.

TEAMS was utilized to generate the design. The following pages are from the TEAMS report. Figures 1

through 5 show the project area. Figures 6 through 11 depict engineered habitat structures.

Figure 1. Locator Map for the Marx Creek Project Area. Tongass National Forest, Alaska.

Figure 2. Locator Map for the Marx Creek Project Area. Tongass National Forest, Alaska.

Figure 3. Marx Creek 2013 Spawning Channel Enhancement Project Areas. Tongass National Forest, Alaska.

This work occurred in 2009 &

2010.

Proposed Project Goals and Objectives Goal 1. Restore and maximize production of chum, pink and coho salmon. Restore and maximize salmonid productivity within the Marx Creek spawning channels by restoring water quality and spawning habitat conditions to exceed standards required for optimizing salmonid population production.

Goal 2. Increase water volume residency and increase ponded water surface area to increase maximum water temperatures; Increase maximum water temperature during peak chum spawning periods to greater than 6⁰ C in the North Channel of Marx Creek.

Objective 2A. Increase the pond surface area of upper Marx Creek from 0.7 acres to 1.85 acres.

Objective 2B. Increase the wetland pond surface area volume ratios from 1.0 to 0.5.

Objective 2C. Attenuate flow within constructed ponds from 2,520 ft3 per hour to 0.720 ft3 per hour.

Objectiave 2D. Construct 504 feet of side slew channel to connect existing wetlands and warm water

sources (Figure 5).

Objective 2D. Increase and maintain 70% direct overhead sunlight onto constructed ponds during

summer months.

Goal 3. Restore, increase and maintain high quality spawning habitat within Marx Creek to reduce egg

to fry mortality and maximize fish production. Increase and maintain high quality spawning habitat to

greater than 6,000 yd2 (greater than 3,000 yd2 per river mile) within Marx Creek.

Objective 3A. Modify weirs and construct spawning glides to maintain water velocities between 0.6

ft/sec and 2.8 ft/sec [Johnson et al. 1971].

Objective 3B. Modify weirs and construct spawning glides to maintain spawning bed depths between

0.5 feet and 3.3 feet [Soin 1954].

Objective 3C. Construct and supplement spawning grounds with spawning gravels containing less than

11% fines (sand and silt) [Rukhlov 1969].

Objective 3D. Increase hiding cover for adult salmon to 3 ft2 per linear foot along the margins of the

spawning channel to reduce predation mortality.

Proposed Project Actions The 2013 Marx Creek Spawning Channel Enhancement Project proposes to modify constructed habitat

to restore and maximize salmon production. The following project actions are designed to achieve the

project goals and objectives. The proposed project actions are:

1. Increase North Pond perimeter area from 0.7 acres to 1.85 acres. Increase South Pond

perimeter area from 1.1 acres to 2.0 acres. Two and eight tenths acres of total new wetland

pond complex area created.

2. Decrease the pond area to volume ratio from 1.0 to 0.5.

3. Construct pond outlets to attenuate water volume flow rates from 2,520 ft3 per hour to 0.720 ft3

per hour.

4. Construct 504 feet of side slew channels to connect 7.3 acres of existing wetlands and warm

water sources (Figure 5).

5. Thin trees within 60 feet of the wetland pond perimeter (4.5 acres) to increase direct solar input

to constructed pond water surface. Thinning would be emphasized on the south and west edges

of the North Pond (3.5 acres). A small amount of thinning (1 acre) would occur on the south side

of the South Pond. Thinned trees would be utilized to create habitat structures which provide

habitat complexity.

Project actions 1-5 are designed to increase solar input and elevate stream temperature in the North

Channel to greater than 6⁰C during peak chum spawning and immigration periods.

6. Rehabilitate 1.8 acres of spawning channel stream banks; stream bank slopes would be reduced

to approximately 3:1, covered with topsoil and replanted with native vegetation to reduce bank

sloughing, and coarse and fine sediment input. Material excavated from the stream banks and

spoils generated from the 2010 excavation would be hauled to the designated stockpile site.

Approximately 3.7 acres west and north of the South Pond Wetland Complex would be used as

the project rock disposal site (Figures 4 & 5). Top soil would be scalped from the pond areas and

used to rehabilitate stream banks. Rooted plants and live stakes would be planted in the fall and

spring following restoration.

7. Construct adult salmon hiding cover structures. Large wood structures such as constructed

undercut banks would be installed along the margins of high use spawning grounds to provide

hiding cover and predator refuge for adult salmon.

8. Modify up to 4 weirs in the north channel, construct spawning glides and augment spawning

beds with clean gravel to:

Maintain water velocities at between 0.6 ft/sec and 2.8 ft/sec

Maintain spawning bed depths between 0.5 feet and 3.3 feet

9. Rehabilitate 11,733 square yards of spawning grounds via suction dredge to reduce fine

sediment levels to less than 11% fines (sand and silt).

In order to facilitate implementation of the above actions, 5,750 feet of existing access roads would be

reopened. Reopened access road segments would be decommissioned (de-compacted and ripped to a

minimum of 24 inches in depth) at the conclusion of the project. Large wood would be scattered across

the decommissioned road prism and planted with the Tongass NF approved seed mix. Access from the

Salmon River Road would be blocked with large boulders to prevent vehicle access.

The excavation activities would generate up to 35,000 cubic yards of material. Spoils would be shaped

and seeded.

Figure 4. Marx Creek Project Area Existing Conditions. Tongass National Forest, Alaska.

Figure 5. 2013 Marx Creek Spawning Channel Enhancement Project Proposed Actions. Tongass National Forest, Alaska..

Figure 6. FMF Hiding Cover and Predator Refuge Structure Plan View.

Figure 7. . FMF Hiding Cover and Predator Refuge Structure Cross-Section View.

Figure 8. Constructed Riffle and Spawning Glide Design.

Figure 9. Soil Bio-Engineered Stream Bank Designs.

Figure 10. Constructed Undercut Hiding Cover and Predator Avoidance Structure Design Cross-Section View.

Figure 61. Constructed Undercut Hiding Cover and Predator Avoidance Structure Design Bi-Section View.