CLEAR CREEK Qa’qad Wetland & Floodplain Restoration Manchester’s Stormwater Park Project Kitsap County Public Works Stormwater Division CLEAR CREEK Wetland & Floodplain Restoration Project: The next step in bringing Clear Creek back to life Kitsap County Public Works Stormwater Division The watershed has been through over 100 years of disturbance. Development has increased stormwater runoff, contributing to • Increased stream erosion • Downstream flooding • Loss of aquatic habitat • Water quality problems Recreating the floodplain will allow the stream more room to spread out, The stream has been degraded and slow down, store and filter water in disconnected from its floodplain. wetland and off-channel areas creating more diverse habitats. BEFORE FUTURE-TARGET CONDITIONS Project Goals: To reduce downstream flooding and restore natural functions so the system can manage stormwater while also providing multiple benefits for people and wildlife: • Re-engage the West Fork, East Fork, and Mainstem with their historical floodplain • Remove fish barrier culverts • Enhance habitat • Improve or maintain connections with the Clear Creek Trail System Clear Creek Floodplain Project Kitsap County Public Works East Fork West Fork Project Areas Mainstem Mainstem The Project Team: Project Manager: Design Engineer: Construction: Revegetation: Clear Creek Floodplain Project Kitsap County Public Works BEFORE Construction Restoration Objective: Remove 21 acres of invasive weeds (e.g. reed canary grass, nightshade, blackberry, etc.) Restoration Objective: Remove 30,500 cubic yards of fill material, lowering elevation to re-engage the stream with its floodplain. New stream channel & floodplain This will increase flood storage capacity by over 6 acres, making more room for stormwater. DURING Construction The new meandering channel helps to slow and spread out water, dissipating the power of the big storm flows. Site: West Fork BEFORE AFTER (before revegetation) BEFORE Construction East Fork stream channel: Covered in invasive weeds dominated by nightshade, reed canary grass, and blackberry. BEFORE Construction Restoration Objective: Remove 1,500 feet of Schold Road that ran in the floodplain and alongside the channelized East Fork. Site: East Fork Channel BEFORE AFTER (before revegetation) Site: East Fork Floodplain BEFORE AFTER (before revegetation) Benefits: Restoration• Bank Objective: stabilization Installed• Slows over stream 675 pieces flows of large woody• Creates debris in-stream habitat and complexity that supports diverse aquatic communities Restoration Objective: Planting over 80,400 native trees and shrubs Removed 2 barrier culverts Installed 3 footbridges Enhancing walking trails Improving fish passage BEFORE AFTER Providing education to the public about the impacts of stormwater and the benefits of floodplain restoration. Enhancing connections to the Clear Creek Trail System, a popular walking trail that Project will monitor plants and runs through Silverdale. habitat for a 10 year period. Lessons Learned: • Having an expert in stream restoration design and construction on-site during construction is essential. Lessons Learned: • Partnerships can result in a more effective project. Partnering with Kitsap Conservation District contributed to significant cost savings and a more robust revegetation plan. Lessons Learned: • Planning ahead to stockpile large wood from other projects is beneficial where large quantities are required. This project is part of a much larger effort to “Bring Clear Creek Back to Life” to ” Clear Creek Floodplain Project was the largest culminating project in bringing Clear Creek back to life. Key Accomplishments Summer low flow, West Fork Floodplain Benefits: 6.4 acres of newly created floodplain 3,758 feet of new or enhanced stream length Increased flood storage capacity by 20 acre-feet Winter storm flow, West Fork Key Accomplishments Habitat Benefits: 675 pieces of large wood installed 21 acres of invasive weeds removed 80,400 native trees & shrubs installed 2 barrier culverts removed Enhanced habitat for more diverse wildlife communities Key Accomplishments Benefits to Citizens: 3 footbridges added Enhanced walking trails Providing ongoing public education about the benefits of floodplains, restoration, and salmon. Winter Storm Events: Year 1 Fall low flow Winter storm flow After 2 inches of rain in a 24-hour period. The floodplains Site: East Fork contained stormwater and did not flood adjacent roadways. Manchester Stormwater Park Puget Sound’s First Stormwater Park Entire community’s rainwater in one little park Goals: • To improve the water quality at Pomeroy Park for swimming, wading, and fishing. • Create a multifunctional stormwater facility - that doesn’t look like a stormwater facility. • Also have it be something that the community could use. The Project Team: Project Manager: Kitsap County Public Works Christopher W. May, PhD Design Engineer: Parametrix David Dinkuhn, PE N.L. Olson & Associates, Inc. Norm Olson Construction: NW Cascade, Inc. Chris Quesenbury Rainwater from 100 acres of urban development washes a variety of pollutants into the storm system. The storm system removes trash and debris before flowing into the park. Within the park, stormwater is filtered through the rain garden soils or the treatment cells. Once treated, the cleaner rainwater is returned to the storm system and discharges into Puget Sound. Key Innovations: • Treats 100 acres of stormwater runoff • Achieves current treatment standards of 91% of storm flows • Cleaner runoff entering the popular Puget Sound swimming beach at Pomeroy Park • Community input and partnerships A green infrastructure & community space A more sustainable Manchester.