Meeker Creek Channel Restoration

Before this project was completed, Meeker Creek flowed through a straight man-made ditch in a suburban neighborhood of Puyallup, Washington. The artificial nature of the creek caused problems for residents and wildlife alike. Poor water quality and a lack of spawning and off-channel habitat meant very low salmon populations, and the creek often flooded during rain events, affecting nearby homeowners.

To address these problems, the City of Puyallup decided to move 1,100 feet of Meeker Creek into a new channel. The project was part of a comprehensive effort to improve stream water quality to meet a Washington State Department of Ecology mandate and improve storm water management throughout the city.

The city hired GeoEngineers to develop conceptual designs, final bid-ready construction plans and specifications for a new, naturally winding stream channel. The plans included a wetland floodplain to improve water quality, reduce flooding, and improve salmon habitat. The team decided to route the new channel through an area of invasive reed canary grass—simultaneously removing this undesirable vegetation while avoiding any impact on nearby riparian plantings from an earlier mitigation project.

The restored section of Meeker Creek flows into Clarks Creek, a larger stream. Meeker Creek’s much lower base flow and higher response flow from storms and groundwater created a hydrology challenge for GeoEngineers as the team had to balance the dramatic differences between the two flows at their confluence. By installing a stream gauge and developing a hydraulic model to adjust for observed results, the team was able to predict the behavior of the new Meeker Creek channel.

The new floodplain is predicted to reduce flooding in adjacent residential areas and increase fish habitat. By designing the marsh to flood frequently as water levels fluctuate, the team encouraged sediment deposition in the freshwater marsh region of the channel. At the confluence with Clarks Creek, the new channel featured a low velocity area to provide off-channel refuge for juvenile salmon, an important habitat type that was missing from the old stream channel and Clarks Creek.

The City of Puyallup contracted with LKE Corporation to perform excavation and construction according to design plans. Watch the video below, produced by LKE, to see Meeker Creek under construction.

Approach

• Throughout the design, the team included elements to improve water quality and aid the city’s broader efforts to comply with the Washington State Department of Ecology’s Total Maximum Daily Load (TMDL) mandate. These strategies included stream riffles to raise water-dissolved oxygen levels, a floodplain that promotes sediment deposition, and numerous willow tree plantings.
• The design included willow trees in the floodplain and along the new channel to reduce water velocities in the floodplain to promote sediment deposition, shade the new creek channel to reduce water temperatures, exclude water waterfowl to reduce fecal coliform levels, and add organic matter to the flood plain to encourage wetland establishment.
• The team prepared project environmental documentation and assisted with obtaining project permits including SEPA determination, a USACE permit, Hydraulic Project Approval, and other permits.
• GeoEngineers measured water flow and then used a hydraulic model to adjust observed results to predict the behavior of the new channel and set the elevation of the Meeker Creek tailwater section at confluence with Clarks Creek.
• GeoEngineers completed a detailed inventory of existing trees that would be removed during project construction, and identified how to integrate them into the project as habitat-enhancing wood structures in the channel and other site areas.
• To manage the significant runoff from the surrounding neighborhood, GeoEngineers also designed a storm water treatment system that routed area storm drains to an Ecology-approved treatment system. The runoff is now intercepted and treated before discharge to the creek.

Results

By carefully measuring pre-construction channel flows and modeling the future behavior of Meeker and Clarks Creeks, GeoEngineers’ River Science Team designed and delivered comprehensive plans for a natural channel and floodplain. The overall design of Meeker Creek will significantly improve water quality and salmon habitat and reduce the risk of flooding in adjacent residential neighborhoods.