Project Location: Pella, Iowa
Synopsis of work:
Ames crews continue work on construction to retrofit an existing dam to generate green, clean power at the Red Rock Hydroelectric project in Iowa.
Crews spent 18 months performing civil and underground work, followed by constructing the powerhouse, located downstream of the Red Rock Dam, and the intake structure, located upstream. The spiral case walls, floor and roof were built, along with concrete draft tubes that preceded installation of the turbine assemblies.
In early 2017, the draft tube liners were the first large embedded components set for the turbine-generator units. Stacked vertically with other components, this assembly directs water through the turbine to produce electricity. Crews also completed one of two penstocks—large pipes that carry water from the upstream intake structure through the dam and into the spiral case. When operating, water will enter the spiral case through a penstock, the turbine turns the generator and electricity is generated.
Throughout the year, crews completed the center and most important parts of the powerhouse, which required stacking multiple embedded parts and constructing the concrete portions of the supporting generator embedment anchors. By year-end crews had begun to install other mechanical support systems within the completed portions of the powerhouse and began the complicated electrical cable tray system that will carry miles of wires within the powerhouse.
By the end of 2017, the specialized concrete of the new intake structure was taking shape and beginning to reveal itself near the top of the cofferdam.
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