The work on this project consisted of the fabrication-installation of a bulkhead/stoplogs system, dewatering of the spill bay, concrete demolition, concrete anchor installation, placement of new 35 foot tall spillway flow deflector with high velocity concrete finish (2,400 CY), heavy hoisting and a diving operation to facilitate increased fish passage through the existing hydroelectric facilities. The temporary stoplog/bulkhead system was installed, with the use of USACE-approved divers, to withstand 55 feet of static head pressure as designed by SCG. The work also included relocation of two 55-ton top spillway weirs at the forebay deck, which required engineering calculations for deck loading conditions of the existing facilities.
The scope of the work included the following:
- Saw cutting and demolition for the removal of 24 each existing concrete weirs within the existing fish ladder
- Removal of existing sill gates, gate actuators, counting station crowding system, counting station window, and associated electrical components
- Construction of new fish ladder concrete weirs and motor operated flow control gates between the fish ladder weirs
- Replacement of the diffuser panels at auxiliary water supply entrance to fish ladder
- Modifications to the existing fish counting station including the replacement of the existing bulkhead, picket leads, crowder, light box and the addition of a window washing system.
Total Project Value: $4.42 million & $2.35 million
Slayden Construction Role: General Contractor and Primary Subcontractor
Owner: US Army Corps of Engineers