Soos Creek Fish Hatchery
Originally constructed in 1901, the existing Soos Creek Fish Hatchery was one of the first built in Washington State. In an effort to replace failing aspects of the existing hatchery, and to upgrade the hatchery to assist the Washington Department of Fish and Wildlife meet new production goals, the Soos Creek Fish Hatchery Project has been undertaken. The project includes construction of a new comprehensive fish hatchery on the opposite side of the creek from the existing hatchery. Components of the new hatchery include: New obermeyer weir, juvenile bypass, fish ladder, intake structure with mechanical building, adult pond, raceway ponds, drain box, heavy settling pond, pollution abatement pond, distribution box, round FRP ponds, hatchery building, fine settling pond, a new bridge, office building and associated site piping and heavy civil work. The project requires that in water work be completed in two in-water work windows. After completion and commissioning of the new hatchery, the existing hatchery will be demolished, with specific salvage of required historic items.
Lower Russell Levee Setback – Phase 1
This project is the first phase of two to protect the City of Kent from flooding of the Green River. The project consists of a 2,500 lineal feet of concrete flood wall that includes architectural wall finishes depicting fish and blue herons. Other major work includes PCI installing vinyl sheets as part of the wall’s foundation. Construction took place in the winter during record floods which added additional challenges to the sequence of the work. For preparation of the next phase PCI relocated 3,500 lineal feet of waterline and other associated utilities.
Cowlits Falls Fish Hatchery
To help with the reintroduction of anadromous fish into the upper Cowlitz River Basin, Tacoma Power originally constructed the Cowlitz Falls Fish Facility in the late 1990’s. To further refine this effort, Prospect Construction has been contracted to upgrade the current facility. The project requires careful planning, coordination, timing, and temporary bypasses to facilitate the construction of the upgrades, as all work must be performed while the facility remains in full operation. Major components of work include developing an existing spring with an outlet weir, infiltration gallery and pump station, juvenile holding pools, adult handing area, remodeling the sampling building, construction of a new office/storage building, improvements to the existing CFNSC electrical building and replacing an existing air compressor system with a duplex compressor package.
Henderson CSO - Concrete
The Henderson CSO Reduction project involved construction of an underground combined sewer overflow structure for the City of Seattle. In a rain event, the structure captures and stores sewer/storm-water in an effort to prevent release of it into Lake Washington. The challenge of this project was made more complex by its site location between the shore of Lake Washington and residential homes. This only allowed for crane access on one side of the structure, which resulted in concrete pumping and material delivery challenges, and unorthodox construction practices. The project required mass concrete placements, including 6 ft. thick slabs with thermal control monitoring. The 4 ft. thick walls required a one-sided form system. Overall the project required the 10,000 cubic yard structure to be completed in 6 months.
Lake Tapps Headgate
The Lake Tapps reservoir is filled via a flume that diverts water from the White River. The Lake Tapps Headgate project improved the reliability and function of the aging gates that control the flow of water from the river into the flume. The project required completion within a very short time frame, and Prospect was pleased to assist the owner in completing the project a month ahead of schedule. The work included mechanical and structural upgrades to both gates, the addition of electrical and automatic control of the gates to allow for precise remote operation, miscellaneous civil work and diversion of the river back into the flume.