With experience on numerous projects involving wastewater conveyance and treatment systems throughout the Northwest, Herrera engineers provide wastewater characterization process evaluation, facility planning, system design, odor control, contract document preparation, project management, and construction phase assistance from contract administration to inspection. Our conveyance experience includes service area planning, system evaluation and modeling, I/I studies and design of gravity sewers, pumping stations, force mains, and related hydraulic structures. Our treatment experience includes biological processes, solids separation and processing, disinfection, and solids/effluent disposal and reuse. Joining our team of engineers are planners and scientists who provide the permitting, environmental impact assessment, and mitigation expertise required for wastewater projects to meet all regulatory requirements including the Endangered Species Act.

Key Projects

• King Street Regulator Station and Conveyance Odor Improvements – King County
• Engineering Services Including Investigation, Planning, Testing, and Analysis for Thurston County Wastewater Processing System – Thurston County Department of Water and Waste Management
• Brightwater Wastewater Treatment Plant Siting and Conveyance Development – King County
• South Lake Union Stormwater and Wastewater Discharge Business Case Analysis – City of Seattle
• Sweyolocken Pump Station Upgrade – King County
• Soos Creek Conveyance System Improvements Planning – King County
• Cle Elum Wastewater Facility Plan Environmental Impact Statement – City of Cle Elum