WSP Water Solutions

Ecosystem Analysis and Restoration 

Powells Creek Ecosystem Restoration Project Prince William County Department of Public Works | Prince William County, Virginia

Mill Creek Emergency Stream Restoration TC Energy | Washington County, Kansas

Dead Run Stream Restoration

Baltimore County Department of Environmental Protection and Sustainability | Baltimore, Maryland

■ Emergency restoration for 4 miles of stream ■ Design for flood resilience ■ Stream channel stabilization

■ Major stream restoration ■ Total Maximum Daily Load compliance ■ Hydraulic modeling

■ Nature-based stream restoration design ■ Water quality improvement and habitat restoration ■ End-to-end project delivery WSP led the rehabilitation of the Dead Run Stream, which had been severely impaired by vertical incision, entrenched channels, eroding streambanks, perched floodplains and fine sediment covering the natural gravel bed. These conditions degraded aquatic habitat and contributed significant sediment and pollutants to the Bay. To address these challenges, WSP designed a sustainable solution that maximized environmental benefits by using natural materials and bioengineering techniques. The project delivered substantial improvements in water quality, habitat restoration and community value within this urban stream corridor. WSP’s scope included a functional value assessment to determine the extent of stream impairment, defining construction limits, developing treatment concepts and construction documents, providing expert consultation during construction, overseeing implementation and conducting long-term post construction monitoring. The resilience of the design was demonstrated shortly after construction, when a 10-inch rain event caused widespread flooding nearby but resulted in only minimal, localized damage to the newly restored streambank.

Following a major crude oil spill from the Keystone Pipeline in December 2022, TC Energy engaged WSP to lead the emergency restoration of approximately 4 miles of Mill Creek, a stream in northeast Kansas. The project aimed to stabilize the stream channel, restore ecological function and mitigate environmental damage. WSP provided full-service design, permitting and construction oversight. Restoration techniques included soil lifts, rootwad revetments, large woody debris grade control, toe wood and boulder weirs. The team also replaced the Thunder Road low-water crossing with a 170-foot, three-span bridge to improve flood resilience and aquatic connectivity. The project restored 11.1 acres of riparian habitat and 5.4 acres of streambank using native vegetation. WSP developed a long-term monitoring plan with geomorphic and vegetation assessments triggered by US Geological Survey gauge data. Praised by the US Army Corps of Engineers for its rapid and effective response, the project exemplifies WSP’s ability to deliver ecological uplift under emergency conditions while meeting regulatory and community expectations.

WSP led a multi-phase stream restoration initiative along Powells Creek, a fifth-order perennial stream flowing from Lake Montclair to US Route 1. This project required precision and care, as its flow included a major crossing under the high-traffic Interstate 95. The Powells Creek restoration aimed to support Prince William County’s Total Maximum Daily Load compliance and watershed improvement goals. The restoration spans over 6,600 linear feet of mainstem and 930 feet of tributaries. WSP’s scope of work included geomorphic assessments, 2-D Hydraulic Engineering Center River Analysis System hydraulic modeling, Federal Emergency Management Agency floodplain coordination and restoration design. Our team was responsible for channel realignment, floodplain reconnection, riffle-run-pool morphology restoration and in-stream habitat enhancements using natural materials. WSP’s team has delivered comprehensive design packages and coordinated with stakeholders to ensure ecological and community resilience.

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