Friends of the Issaquah Salmon Hatchery

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https://issaquahfish.org

Posts by David Gowing:

Steven Holland, Treasurer

Steve Holland is delighted to serve on the FISH board and feels that it is all our responsibility to pay it forward for the next generation (especially his daughters who love to fish) to keep the salmon coming home.  He has been volunteering in multiple roles at the hatchery for the last two years and feels more can be done to educate and build towards the future – together as a community.

Steve learned how to fish in the Upper Peninsula of Michigan with his Dad, uncles, and cousins for Muskie, Northern Pike, Coho, and Steelhead.  Since then, he has fished around the world from New Zealand to Russia, but Chinook remains his favorite.  Steve launches out of both Edmonds and Point Roberts Marina with his Grady-White.

Steve is quasi-retired and is a recovering Chief Information Officer for multiple Fortune 100 companies.  Since he still loves technology, he has found himself helping startup companies in Bellevue and San Francisco get launched and provides enterprise “Crisis CIO” help when needed. 

Madeline Fish

Madeline Fish is passionate about community engagement and the opportunity to educate Eastside residents regarding the Issaquah Fish Hatchery. An Issaquah resident since 1992, she loves living and hiking on Squak Mountain and working in Issaquah for another locally-based non-profit organization. She’s a VOICE mentor in the Issaquah School District and volunteers with other local organizations. She’s an avid reader and sourdough aficionado. She and her husband, Chris, love boating in South Puget Sound.  Madeline joined the FISH Board in 2019.

Robin Spicer

“Spicer,” a local and regional graphic designer with extensive marketing success, has lived, worked and volunteered in the Issaquah community since 1984. Her portfolio includes branding, packaging and promotions for real estate, tourism, sports, tech, finance, food/beverage and manufacturing companies, as well as small business, community non-profit organizations and festivals. (Spicer was the designer of the Issaquah Salmon Days Festival theme and logos from 1995 to 2019 and original FISH logo in 1992.)

With a continuous passion for design, community, salmon and the environment, Spicer relishes her free time swimming, reading, writing and celebrating all things – ideally along rivers, lakes, mountains or in our local haunts – with family, friends and partner Rob.

Laughing Jacobs Creek

About Laughing Jacobs Creek

Laughing Jacobs Creek drains 3,600 acres of Issaquah and Sammamish — including Beaver Lake and Laughing Jacobs Lake — into the southeast corner of the Lake Sammamish. It is one of four primary spawning creeks for the endangered kokanee of Lake Sammamish. 3,500 feet of the creek are available to migrating fish up to Laughing Jacobs Falls. However, a 48” pipe culvert under East Lake Sammamish Parkway (ELSP) presents a significant barrier to migration.

The restoration project area within the greater Issaquah/Sammamish area.
Gallery: The Restoration Plan for Laughing Jacobs Creek

History of the Area
The project area is located just north and east of the Lake Sammamish State Park boat launch and ELSP. In the 1800s, this area was deforested (including the creek path), the creek was channelized, wetlands near the lake shore were converted to farmland, and a railroad was constructed along the east side of Lake Sammamish to serve the numerous lumber mills along the lake shore. The earliest arial photograph of the area, taken in 1936 (see gallery), shows a still-mostly deforested landscape, the channelized creek, and farmlands, while the railroad is gone, indicative of the demise of the local timber industry following areawide deforestation. Some land has been restored to wetland, with the notable exception of the boat launch area and the adjacent private properties to the north.

The Restoration Project Area

  1. East of ELSP: Laughing Jacobs Falls drops down from the Plateau to Hans Jensen State Park (the project’s eastern border). Here the creek runs through mature forest, but the corridor is narrow and restricted by its proximity to ELSP. There is some armoring of the creek channel. A second tributary, Many Springs Creek, flows from the north. Many Springs Creek is also considered potentially good habitat for kokanee. (Note: it currently crosses under ELSP via a separate, adjacent culvert.)
  2. ELSP: Laughing Jacobs Creek flows under ELSP via a 48″ pipe culvert. While kokanee have been observed on the upstream of this culvert, migration is highly dependent on flow, and is therefore considered a significant barrier.
  3. West side of ELSP: Laughing Jacobs Creek is joined by Many Springs Creek, and flows through three private lots on its way to the lake. (The mouth is potentially good rearing habitat for juvenile Chinook.) These lots were once farm land. The creek in this reach has not been allowed to recover, having the following characteristics:
    1. Lawn and landscaped fields
    2. Little riparian cover or shade
    3. Some areas are choked with invasives
    4. Armored banks

Goals of the Project

  1. To replace the 48″ pipe culvert at ELSP with a fish-passable culvert, and
  2. To restore reaches of Laughing Jacobs Creek upstream of ELSP (WILL THERE BE ANY RESTORATION OF MANY SPRINGS CREEK???) for spawning kokanee, coho and cutthroat trout.

Future goals: work with private landowners on the west side of ELSP to restore riparian and in-stream habitat, including the mouth of the creek at Lake Sammamish.

The Chosen Restoration Plan
The Kokanee Work Group evaluated three “alternatives” and selected Alternative 3. The restoration plan will:

  1. Replace the two existing culverts for Laughing Jacobs Creek and Many Springs Creek with a single, 25-foot wide box culvert passage with fish-friendly features.
  2. Relocate the confluence of Many Springs Creek and Laughing Jacobs Creek to the east side of ELSP — to within the boundaries of Washington State Parks.
  3. Realign (relocate) a significant section of Laughing Jacobs Creek, away from the east side of ELSP, and further into mature-forest State Park land. This will:
    • Provide a much larger riparian buffer along both sides of the channel.
    • Allow for better long-term natural “recruitment” of fallen wood from the existing forest. (Fallen wood, over time, creates stream diversity, cover for fish, depressions in the stream bed, and helps retain spawning gravels.)

Highlights of the proposed creek channel:
It is intended to create a “mini floodplain within the stream corridor.”

  • It will be wider, allowing the creek to naturally migrate and sort sediment and gravel.
  • It will be a “two-stage channel” consisting of:
    1. a low flow channel and
    2. thin benches a foot above the channel bottom on each side, in order to spread higher flows across a wider area.

Concerns: Issaquah School District developments upstream

The Issaquah School District is constructing three schools within one mile upstream of the project area: a high school, a middle school and an elementary school. These projects will include a significant amount of impervious surface, thereby contribute additional flow to the creek during storm events, while reducing groundwater recharge, depriving the creek of that water during the summer. Increased flow during storm events will contribute to scouring of the creek bed and spawning beds. The City of Issaquah and the Kokanee Work Group should consult the school district on what additional stormwater measures can be taken to protect Laughing Jacob Creek salmonids. Additionally, the planned artificial turf football field should be reviewed for its potentially lethal effect on coho salmon attributable to rubber infill derived from recycled tires.

Zackuse Creek

About Zackuse Creek

Zackuse (also spelled Zaccuse) Creek drains a 240-acre watershed into Lake Sammamish. It is one of the four primary creeks used by endangered kokanee of Lake Sammamish. The creek descends from the Plateau through mature forest to what was previously farmland.

In the 1800s, the area was deforested and much was converted to farmland. The Seattle Lakeshore & Eastern Railroad crossed Zackuse Creek approximately 500 feet upstream of Lake Sammamish, and a lumber mill was located on the shoreline within one mile to the north. Since the 1980s, significant residential development has taken place in the upper watershed.

Zackuse Creek Restoration Project
Gallery: Zackuse Creek restoration project

Features of the 2018 Zackuse Creek restoration project:

  1. Replaced pipe culvert barriers with fish-friendly box culverts. The new culverts provide wide, unobstructed fish passage, designed to emulate a natural stream bed. Locations:
    1. East Lake Sammamish Parkway (ELSP)
    2. East Lake Sammamish Trail
    3. East Lake Sammamish Shore Lane NE
  2. Realigned (relocated) and restored 400 feet of creek:
    1. Away from: 1) where it was choked by invasives, which had trapped fines and sands and destroyed spawning habitat; and 2) where the channel was straight and provided no habitat. 
    2. Inline with the new box culvert at ELSP.
    3. Design goals:
      1. Enable the creek to sort gravel and sediments to maintain good spawning material for kokanee.
      2. Prevent sedimentation of the creek channel by allowing fines and sands to flush through to Lake Sammamish and outside of the creek channel to the wetlands.
      3. Prevent the stream channel from migrating within the alluvial plain in order to maintain alignment with the culvert at ELSP.
      4. Establish riparian growth with the goal of longterm stream diversity.
    4. Design features:
      1. NEED HELP HERE BECAUSE THE ACTUAL DESIGN DIFFERS FROM THE PLAN.

Challenges of an alluvial plain
The plateau above the project area is characterized by glacial deposition and, during storm events, Zackuse Creek carries a high load of sediment and gravel. The project area is, in fact, historically an alluvial plain — where sediment drops off as flow fans out. Typically, within such an environment, the creek would naturally migrate and braid, and this presents a challenge for longterm alignment with permanent structures — in this case, the culvert under East Lake Sammamish Parkway.

The new section of creek was designed to maintain a defined channel, with some room for the creek to migrate within the channel. The ongoing challenge will be how to preserve its alignment with the culvert while not creating sediment deposition buildup within the channel.

As of February, 2021, the new box channel culvert has accumulated significant sediment and will need to be monitored and possibly modified to ensure sediment flows through to Lake Sammamish, as intended, rather than create flooding problems.

Significant issues remain upstream

Immediately upstream of the project area (Reaches 5 & 6 in the gallery) is an area of transition to mature forest. These reaches should demonstrate what recovery looks like. Instead, they show the effects of surging stormwater runoff from residential development in the upper watershed. Paved surfaces and roofs (impervious surfaces) have altered the flow of the creek. Storm drains, which convey rain water to the creek quickly rather than allow it to percolate into the groundwater table, overload Zackuse Creek during storm events, scouring the creek bed and eroding natural features of the channel. More than that, all creeks rely on groundwater for flow during dry periods, and development in the upper watershed has blocked a significant portion of that recharge for Zackuse Creek.

Evidence A in Zackuse Creek: in 2012, stream surveyors documented a __-foot long incised channel in Reach 5 (see gallery). They concluded that this incision in the creek channel is a result of the creek not being able to naturally withstand the new volume of storm water flow from developments upstream.

Evidence B in Zackuse Creek: at the upstream end of this incision — at the time — was a 5-foot high waterfall. When the surveyors returned in 2015, the waterfall had receded over 150 feet upstream (extending the incised channel). It is most likely that this incision has eroded further upstream since that time.

Zackuse Creek Restoration Project
Gallery: Problems remain upstream

This creekbed incision & recession was responsible for much of the sediment deposition in the lower reaches prior to the realignment of the creek in 2018. The new, realigned channel has been designed to compensate for this sediment overload, but the continuing erosion, incision and recession of this upstream reach will destroy further habitat upstream until it is addressed. 

Special Note: Collaboration
This restoration project was initiated in 2012 when Wally Pereyra, a private landowner and kokanee advocate, contracted an environmental-engineering firm to evaluate conditions on Zackuse Creek from the mouth of the creek to the east portion of his property (over 1,300 feet total). Mr. Pereyra funded a second study in 2015, all with the intent of jumpstarting a formal review process for the creek. His efforts led to a restoration partnership of the following agencies and groups:

  • City of Sammamish
  • King County Parks
  • Kokanee Work Group
  • Snoqualmie Tribe
  • Trout Unlimited
  • Washington State Fish and Wildlife
  • Private property owners.

Ebright Creek

About Ebright Creek

Ebright Creek is located on the east side of Lake Sammamish, and drains a 1.4 square mile watershed. It is one of just four remaining kokanee spawning streams of Lake Sammamish, and the mouth of the creek is important for rearing juvenile Chinook salmon. In the 1800s, the surrounding area and riparian land was deforested, the creek bed was channelized, land was converted to farmland, and a railroad crossed the creek approximately 500 feet upstream of Lake Sammamish to serve the nearby lumber mills along the shoreline. Today, pipe culverts under East Lake Sammamish Parkway (ELSP) and the East Lake Sammamish Trail (location of the former railroad) present barriers to fish migration, and much of the habitat remains degraded.

Gallery: Ebright Creek restoration project details
Gallery: Ebright Creek restoration project details

Restoration and planning for Ebright Creek has been ongoing since the 1990s
King County first restored a section of the creek in the 1990s. Beginning in 2012, a private landowner, the City of Sammamish, the Kokanee Work Group and its partners developed restoration plans and restored some sections of the creek. (Detailed timeline included below.) In 2021 and 2022, the City of Sammamish and King County will remove pipe culvert barriers. Combined, these upcoming projects will open up 1.11 miles of quality spawning habitat upstream to kokanee.

Details of the Upcoming 2021/2022 Restoration Projects
In 2021, the City of Sammamish will:

  • Replace two 30-inch concrete culvert pipes under East Lake Sammamish Parkway with a fish-friendly 14’ wide x 9’ tall box culvert. The new culvert will feature “meander bars” to create channel sinuosity through the passage.
  • Re-align the creekbed east of ELSP to the new box culvert.
  • Enhance and restore riparian habitat of the new creek channel with large woody debris (LWD) structures and boulders.

In 2022, King County will:

  • Replace the two culvert pipes under the East Lake Sammamish Trail with fish-friendly box culverts. Details pending.

Timeline: The History of Restoration on Ebright Creek:

1990’s: Habitat improvements upstream of ELSP.
King County installed 20 pieces of large woody debris (LWD).

2012: Notable homeowner conservation effort.
Wally Pereyra, a landowner committed to kokanee conservation, replaced a __ inch culvert on his property with a concrete archway bridge to provide unimpeded fish passage. The new passage will also prevent sediment deposition. Invasive plants were removed from the middle reach and replaced with native trees and shrubs. 

Ebright Creek Pereyra project - 6 of 9
View the Gallery

2012: City develops Ebright Creek Enhancement Plan
The City of Sammamish contracted environmental engineering consulting firm David Evans and Associates, Inc. to produce the Ebright Creek Enhancement Plan, which evaluated the creek from Lake Sammamish to approximately 800 feet upstream of ELSP. The plan listed these issues and recommendations:

  • Issue: The reach just upstream of ELSP was braiding and meandering.
  • Issue: The reach downstream of ELSP to Lake Sammamish was channelized and “incised” by development.
    • Recommendation: regrade in order to: 1) re-establish the floodplain riparian zone, 2) reduce scouring and incision, 3) provide diverse channel habitat, and 4) improve opportunities for spawning.
  • Issue: A portion of the north side of the creek, upstream of ELSP, had been filled in the past.
    • Recommendation: Remove the fill and regrade the north side of the creek in order to: 1) increase riparian wetland-type habitat and 2) reconnect it to the floodplain.
  • Recommendation: Add large woody debris (LWD) structures along approximately __ feet of creek upstream of ELSP. This would add to the enhancement work performed by King County in the 1990’s, and provide habitat diversity and bank stabilization.
  • Issue: The riparian zone along the creek lacked conifers and was overgrown with invasive species.
    • Recommendation: remove invasives, plant natives and over 650 conifers.

2014: The Kokanee Work Group produced a strategic plan to help kokanee.
The Kokanee Work Group produced Blueprint for the Restoration and Enhancement of Lake Sammamish Kokanee Tributaries, which identified specific conservation measures to enhance and protect kokanee habitat around Lake Sammamish. A top priority of the plan was the restoration of Ebright Creek and removal of the culvert barriers.

2017: Removed invasives; planted 2,327 natives.
Mid Sound Fisheries, the Snoqualmie Tribe and Trout Unlimited collaborated with a private land owner to remove invasive species along 600 feet of Ebright creek and replace them with native plants. To ensure success, the Snoqualmie Tribe conducted follow-up maintainance and provided mulch.

Ebright Creek Pereyra project - 9 of 9
View the Gallery

2019: Development of plan to replace the culverts under ELSP.
The City of Sammamish contracted Osborn Consulting, Inc. to develop a final plan to replace the two 30″ culverts at ELSP and restore a portion of the creek in the project vicinity. 

2021: City will remove the culverts and replace them with a fish-passable box culvert.
As discussed aboove, the City of Sammamish will begin construction in June, 2021, and expects to complete it by early fall, in time for kokanee migration in November. 

2022: King County will replace culverts under the East Lake Sammamish Trail.
King County will replace the pipe culverts under the trail with a 14′ wide box culvert.

* The City of Sammamish maintains a web page for the Ebright Creek Fish Passage project to keep the community up to date on every phase of the 2021 project, including regular public presentations and discussions, and comprehensive project documentation. 

Sycamore Restoration Project – Phase 1

Project Description:
This Phase 2 project is a followup to Phase 1 (conducted two years earlier in 2004). The City of Issaquah restored 600 feet of Issaquah Creek in a 4.6 acre area.

Restoration Features:

  • Installed 20 log structures (large woody debris — LWD) in the stream for fish habitat
  • Removed bank fill to improve connection of the stream to the floodplain area
  • Removed invasive plants and replaced with native vegetation.
OLYMPUS DIGITAL CAMERA
Sycamore Restoration Project Phase II (View Gallery)

Lewis Creek

About Lewis Creek:

Lewis Creek drains the northern slopes of Cougar Mountain into the south west corner of Lake Sammamish. The 1,000 feet of culverts under the West Lake Sammamish & I-90 interchange have divided the creek into what is referred to as the “upper basin” (not available to migrating fish, located within the city of Bellevue) and “lower Lewis Creek” (the restoration project area, located within the city of Issaquah).

Lower Lewis Creek supports kokanee, sockeye, coho and cutthroat trout.

History of changes to lower Lewis Creek
A saw mill was established on the property in 1889 near the lake shore, and a railroad ran from a pier at the lake shore, southward, to Cougar Mountain. A historic aerial photo of the area taken in 1936 indicates that: 1) the mill and railroad no longer existed by that time, and 2) the land surrounding the lake — as all land in the area — was the victim of deforestation. Remnants of the mill could still be found in the 1960s, including a large sawdust waste pile and lumber several feet thick submerged in Lake Sammamish.

In the 1980s, lower Lewis Creek experienced a large increase in residential development. The stream bed and riparian areas are owned by over 30 separate landowners. Urbanization has increased storm runoff to the creek, resulting in erosion and sedimentation of the channel, degradation of spawning habitat, and deposition of sands and fines at the mouth (the delta), which created a shallow, wide area with no deep pools for rearing. HAS THIS BEEN ADDRESSED YET? NEED PHOTOS AND RECORDS.

Gallery: Lewis Creek
Gallery: Lewis Creek
Gallery: History of Lewis Creek
Gallery: History of Lewis Creek

Goals for Restoration of lower Lewis Creek:

  • Remove any barriers within the reach.
  • Stabilize the eroding channel.
  • Create pools and other stream diversity to improve habitat for kokanee spawning.
  • Reduce fine sediment deposition within the channel.
  • Restore the mouth of the creek to provide rearing habitat for juvenile chinook.

Project Phases

2008: Removal of fish barrier

  • Location: just downstream of SE 44th Street, roughly midway between Lake Sammamish and I-90.
  • The City of Issaquah installed five rock weirs to create a series of steps to allow upstream migration past a two-foot-tall barrier. 

“Phase 1” (2011): Evaluate lower Lewis Creek (DID THEY WORK ON THE DELTA?)

The City of contracted Northwest Hydraulics to develop a restoration plan for the 4,125 feet of lower Lewis Creek. The plan identified four distinct “Reaches.” (See gallery.)

“Phase 2” (2015): Identify and restore the highest priority reach along lower Lewis Creek
Based on the evaluation in Phase 1, the City of Issaquah contracted Northwest Hydraulics to identify and create a restoration plan for the highest priority reach along the creek. Reach 3 was identified as having experienced channel degradation, creek bank erosion, and the loss of much of its fine bed material (gravel sizes 1/4” to 3”), and was selected to be the project area. 

Restoration work conducted on Reach 3:

  • Added Large Wood Debris (LWD) to the stream bed, spaced approximately 20-30 feet apart, to: 1) create pools, 2) promote deposits of smaller gravels, 3) make the channel more resistant to high flows.
    • THE 30% PLAN MENTIONED LATERAL BOULDER WEIRS EMBEDDED INTO THE CHANNEL. DID THIS HAPPEN???
  • Planted native riparian vegetation.

The City of Issaquah worked in partnership with the Meadowbrook Point Homeowners Association.

Gallery: project area overview
Gallery: project area overview
Restoration of Lower Lewis Creek (Click to View Gallery)
Gallery: Restoration work performed

Potential for Future Restoration

  • “Upper reach” restoration:
    • 2,400 feet of creek, starting upstream of the 2015 lower Lewis Creek restoration project up to the culvert at I-90, have yet to be restored to:
      1. Make the channel more resistant to high flows, and
      2. Capture fine gravels suitable for spawning.
  • The Lewis Creek upper basin:
    • The major culverts under the interchange are a barrier to fish migration.
    • The ravine in this basin was characterized in 2014 as being generally steep and unstable, with the potential to provide a limited amount of spawning habitat. 
    • Due to the high cost of upgrading the culvert to a fish passage at the interchange, the upper basin was outside the scope of consideration in 2014.

Squak Valley Park

Features:

  • Removed a streamside levee and restored 6 acres and 1,100 feet of stream.
  • Added wood and wood structures for stream habitat and hydraulic diversity.
  • Planted native riparian vegetation.

 

 

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Squak Valley Park restoration (Click to View Gallery)

Removal of the Issaquah Hatchery Dam

This 12-foot high diversion dam was built in 1936 to provide water to the downstream Issaquah Salmon Hatchery. The dam provided an inadequate, steep, narrow fish ladder which severely restricted fish passage to 11 miles of upstream habitat. It was common for salmon to become stranded and die at this impasse during low flows. In other cases, adult returning salmon would give up, turn around and go downstream.

The 2005 Chinook Salmon Conservation Plan for WRIA 8 identified this dam as a significant barrier, and at that time the Army Corp of Engineers proposed to build a replacement dam and fish ladder. Those discussions did not move forward. In 2008, Washington Department of Fish & Wildlife partnered with the City of Issaquah and hired engineering consulting firm AMEC to take on the challenge to develop a better solution to continue to provide water to the hatchery while allowing easy passage for salmon.

The solution:

  • a series of 13 boulder weirs, which mimics natural conditions and provides a gentle, easily-passable incline for salmon.
  • a water intake structure (to continue to provide water to the hatchery downstream) which provides unobstructed fish passage and a low-maintenance design. (DOES IT SCREEN FOR JUVENILES?)

Additional restoration features:

  • Replace invasives with native riparian vegetation, which Mountains to Sound Greenway Trust will continue to monitor moving forward.
  • Large, in-stream woody debris to provide habitat and stream diversity.
  • Improved fish passage to Cabin Creek, which enters the creek at the site.

Pre-Construction Discussion of the Project

Post-Construction Discussion of the Project

Total cost of the project: $4.8 million

62nd Street Extension

The goal of this ambitious project — the most expensive in City of Issaquah history — was to extend 62nd Street from East Lake Sammamish Parkway to Lake Drive (at the south side of Costco corporate headquarters) in order to facilitate expansion of the Costco corporate campus and associated traffic, while providing significant environmental and community benefits. The City worked in partnership with Costco and the Washington State Department of Transportation. It is an excellent example of a partnership to promote economic growth, improve habitat, and enhance community resources. Environmental consulting firm ESA consulted on bridge hydraulics, fish passage design, channel realignment (a section of the creek was re-located), floodplain analysis and landscape architecture. Project costs totalled $42 million, with funding divided among partners as follows:

  • City of Issaquah: $4 million
  • Costco: $23 million
  • Washington State Transportation Improvement Board and Department of Commerce: $15 million

Features of the project:

  • 62nd Street was extended via an 800-foot bridge to connect Eastlake Sammamish Parkway with Lake Drive.
  • The bridge spans Issaquah Creek and the North Fork of Issaquah Creek.
  • 500 feet of the North Fork of Issaquah Creek was relocated 100 feet west to accommodate the new traffic roundabout.
  • A pedestrian under-crossing was created for the King County trail, eliminating a hazard for pedestrians.
  • Improvement were made to Pickering Trail, including widening it, adding lighting, and connecting it to the King County trail system.
  • Two large storm water detention vaults were added.
62nd Street Extension - Click to Launch Gallery
62nd Street Extension - Click to Launch Gallery

Stream restoration & other environmental benefits:

  • 6 acres were preserved as open space between the North Fork and the main stem of Issaquah Creek. (This was land previously zoned for multi-family residential development.)
  • Created two acres of wetland.
  • Stream restoration design added large wood habitat structures, bioengineered bank stabilization, floodplain benches, and native plantings.
  • While relocating 500 feet of the North Fork of Issaquah Creek, they improved upon the historically very-modified channel by reconnecting the creek to its floodplain, thereby reducing flood risks to local businesses, and improving habitat.
  • Modified the bridge foundations to create fewer piles, resulting in less impact to the wetland.

Videos of the Project

Lake Sammamish State Park

About Issaquah Creek and Lake Sammamish State Park

Issaquah Creek drains a 61 square mile watershed to Lake Sammamish. Its headwaters are Cougar, Squak, Tiger and Taylor Mountains, while its final 6,000 feet reach runs through Lake Sammamish State Park. Unique to our local community, the Issaquah Creek watershed is over 75% forested land. Like most creeks in the area, Issaquah Creek is in a state of recovery, while facing the ongoing challenge of development. In the 1800s, the area was entirely deforested, including the along the creek, which in some locations was channelized and armored. Flatlands in the valley and near the lake shore were converted to farmland. Local hillsides were mined for coal, and until recently, coal mine tailings still contaminated the creek. (CREATE PROJECT PAGE FOR TAILINGS PILE REMEDIATION PROJECT BY CITY OF ISSAQUAH.)

The restoration plan focuses on the entire run of Issaquah Creek through Lake Sammamish State Park.
Gallery: 2022 Issaquah Creek Restoration Project

Washington State Park Commission purchased the two farm parcels that comprise the park in 1951 and 1958. Lake Sammamish State Park was founded in 1953. 

The final stretch of Issaquah Creek — which runs through the park — is important habitat for migrating and rearing salmon. In 2005 it was identified by the Chinook Salmon Conservation Plan as a priority area for restoration efforts. Since then, Washington State Parks & Recreation Commission and the Mountains to Sound Greenway Trust have worked together to restore riparian habitat along the reach, having removed invasive flora and planted more than 50,000 native trees and shrubs along the river corridor.

2022 Restoration Project
Washington State Parks and the Mountains to Sound Greenway Trust have developed a comprehensive restoration plan to restore the entire run of Issaquah Creek within Lake Sammamish State Park. Construction takes place in the summer of 2022.

Project Goals

  1. Use historic channels and side channels to:
    1. Reconnect the creek to the floodplain and
    2. Improve fish habitat;
  2. Increase sinuosity (the natural, winding characteristic) of the creek;
  3. Incorporate large woody material in the stream to create diverse, natural conditions to benefit migrating adult salmon and rearing juveniles.

The four reaches of the project area
The restoration team has identified four unique, adjacent sections (reaches) of Issaquah Creek within the park, each with their own set of characteristics and solutions.

Reach 1: where Issaquah Creek meets the lake

In this reach, the channel is wet year-round. When flow is low, the creek slow moving and at lake level. In the past, the creek bed was channelized, and disconnected from side channels and the floodplain. This reach is appropriate for “short-term rearing habitat”. Chinook in particular linger at creek mouths during their downstream migration.

The Plan:

  • Add 35 pieces of wood throughout reach to create habitat.
  • Construct/excavate a channel to connect the existing creek to the historic creek channel (located to the northeast).
  • Add Large Woody Debris (LWD) structures at the distributary channel to “push flow” from the creek to the new channel.
Gallery: Reach 1
Gallery: Reach 1
  • Add two different sets of LWD to:
    1. Control sinuosity and “channel migration” (the natural tendency of a river to change course over time)
    2. Increase cover for fish
    3. Create “hydraulic complexity”

Reach 2: where the river flattens out into the flood plain

This is where Issaquah Creek desposits much of its suspended sediment. The reach is mostly open with shrubby areas, invasives, and minimal forest (this forest is mostly young). This reach is appropriate for rearing juveniles and for holding areas for returning adults.

Goal for this reach: maintain the existing diverse habitat, and improve its ability to filter downstream-migrating wood debris. (Wood is important to create stream diversity and quality habitat.)

The Plan:

  • Add LWD to provide cover and hydraulic complexity.
Gallery: Reach 2
Gallery: Reach 2
  • Add LWD structures to filter wood traveling downstream from upper reaches.
  • Create a new channel to split the flow, directing water to a historic oxbow.
    • Add LWD and LWD structures in the new channel and the oxbow to provide cover and hydraulic diversity.

Reach 3: Narrow, high velocity flow, little habitat

Reach 3 is characterized by a channel that cuts right through, with no connection to the flood plain, with little habitat for rearing or holding, and features a potential fish barrier during high flow. The limited spawning habitat in this reach is tricky because:

  1. It is not preferred by chinook, which prefer larger gravel sizes, and
  2. While the smaller gravel sizes are appropriate for kokanee, coho and cuttroat, these fish prefer to spawn in smaller size streams.

Goals for this reach: provide hydraulic diversity to this reach to break up the flow, reconnect it to the flood plain and allow it to meander, thereby creating more habitat. 

Gallery: Reach 3
Gallery: Reach 3

The Plan:

  • Grade and install LWD and LWD structures to increase meandering and hydraulic complexity.
    • Initiate meandering by directing flow against stream banks — and removing roots holding banks in place in these areas.
  • Add a pedestrian bridge.

Reach 4: the uppermost reach

This reach features high hydraulic complexity and off-channel habitat. It has limited riparian forest. There is riprap armoring on one channel to prevent channel migration. It is relatively lacking in wood. While this reach is still not preferred by spawning salmon, of all the reaches, it has gravel most suitable for kokanee spawning. However, kokanee prefer smaller tributaries.

Goals for this reach: Increase hydraulic diversity and provide cover for rearing juveniles. 

The Plan:

  • Remove riprap armoring.
  • Add LWD and LWD structures:
    • seven structures to initiate large wood mass jams.
    • 14 pieces along high banks, adding hydraulic complexity and cover.
    • “apex jams” to encourage island and pool formations.
    • “spur jams” to “encourage scour of pools.”
  • Create a channel to split the flow to add hydraulic complexity.
Gallery: Reach 4
Gallery: Reach 4

The expected total cost of the project is $2.5 million.

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