Wholesale Transmission Main Extension and Booster Pump Station
Lakewood Water District
RH2 is assisting Lakewood Water District with the extension of their existing wholesale water transmission main and addition of an associated booster pump station (BPS) by developing and evaluating alternatives, conducting environmental investigations, and preparing the design. The transmission main will traverse approximately 6.8 miles along paved right-of-way and roadway shoulder in unincorporated Pierce County.
In 2018, RH2 conducted critical areas site investigations to assess the presence and location of wetlands, streams, and fish and wildlife habitat conservation areas within 315 feet of the proposed alignment and potential BPS locations. Our team delineated and rated 26 wetlands using methodology from the Western Mountains, Valleys, and Coast Regional Supplement to the US Army Corps of Engineers (USACE) Wetland Delineation Manual and the Washington Department of Ecology (Ecology) Wetland Rating System for Western Washington. We identified 7 regulated streams along the alignment and delineated the ordinary high water line, per Ecology’s guidelines.
RH2 coordinated with state and local agencies, and worked closely with the design team to communicate regulatory requirements and implement mitigation sequencing by avoiding and minimizing impacts to critical areas. Our team subsequently prepared a Critical Areas Report to describe wetland and stream habitat conditions, required buffer widths, and anticipated project impacts. Permitting and design for the project is currently ongoing.