Specifications include, but are not limited to: The Montana Department of Natural Resources and Conservation (DNRC) is seeking proposals from professional engineering firms qualified to comprehensively advise on the sale of hydroelectric power, the sale of the hydroelectric project, and other options if a power or project sale cannot be concluded. The subject work will be performed for the Broadwater Power Project (Project) in Broadwater County, Montana. DNRC will evaluate proposals from firms desiring to be considered for this project. The Project is a 9.66 MW, run-of-river hydroelectric project owned by the DNRC and operated by the State Water Projects Bureau (SWPB). The Project is located on the Missouri River, near the town of Toston, Montana. The site is about 20 river miles downstream of the headwaters of the Missouri River and about 20 river miles upstream from Canyon Ferry Reservoir. The Toston Dam, which retains water for the Project, is a concrete gravity overflow dam, originally constructed in 1940 as an irrigation diversion structure, with a total length of approximately 630 feet. It is 24 feet high to the top of the gravity overflow section and 40 feet high to the tops of the abutment walls on either end. The maximum dam height from the bottom of foundation concrete to the tops of the abutments is approximately 50 feet. The upstream face of the dam is vertical. The downstream face is a modified ogee section with an apron that extends 75 feet downstream from the upstream face of the dam. At either end of the dam, parallel to its axis, are counterfort abutment walls, which extend into the abutments and function as concrete seepage cutoff walls. Between 1987 and 1989, a powerhouse was constructed in the left abutment that contains a single, pit-Kaplan hydroelectric generating unit. The powerhouse is a reinforced concrete structure constructed in the left abutment between 1987 and 1989. Electric power was first generated at this installation in June 1989. The powerhouse is located between the dam itself and the headworks of the Broadwater-Missouri irrigation system. The powerhouse is approximately 160 feet long, with a maximum width of 46 feet and a maximum height above the foundations of about 64 feet. The powerhouse contains a single, horizontally mounted double-regulated Kaplan turbine in a pit-type configuration. The turbine has a capacity of approximately 10 MW at a rated head of 21-feet and a rated flow of about 6630 cfs. Water flows into the powerhouse through two inclined trashracks. The water then flows on either side of a concrete and steel turbine pit, through a set of wicket gates, then through the turbine. Flow from the turbine discharges into a draft tube 30 feet high, 40 feet wide and 90 feet long.
