On-Call Services for Environmental Analysis and Stormwater Project Scoping (WA)

WEST Consultants was a subcontractor to Ecological Land Services, Inc for an On-Call Services Contract for Environmental Analyses and Stormwater Project Scoping. The purpose of the contract was to define appropriate regional stormwater management facilities that would be incorporated in the County’s Capital Improvement Program (CIP) for stormwater management improvements.  WEST was subcontracted to provide expertise to the team in hydrologic, hydraulic, and geomorphic analyses.

WEST conducted hydrologic and geomorphic assessments to help understand the dynamic processes at work in various stream basins and their interrelation with human influences.  The assessment results were used to develop an understanding of how basin conditions influenced current and future hydrology, channel morphology, flooding, erosion, water quality, and fish and wildlife habitat.  The results were also used to form management recommendations and guide the development of capital stormwater or habitat restoration projects.

Major tasks of the work included:

• Collection and review of relevant data and information;
• Field reconnaissance of involved streams and watersheds;
• Geomorphic characterization;
• Geomorphic analysis;
• Hydrologic analysis of historic, existing, and future basin conditions using HSPF;
• Hydraulic modeling using HEC-RAS.