Underwater tower completed Dec. 3; first fish passing through
December 11th, 2009Work on the underwater tower and fish transfer facility was substantially completed Dec. 3, after PGE made the final connections between major components, and fish have begun entering the system.
The first major migration of fish is not expected until February, but dozens of juvenile fish have already followed currents created by the tower and have been transported downstream by PGE biologists. The tower is now undergoing testing, which is expected to continue until mid-January.
The underwater tower draws water off the surface of Lake Billy Chinook, restoring currents disturbed when the dam was built in the 1960s, and allowing migrating fish to find their way to a collection facility where they can be transported downstream of the Pelton Round Butte hydro project, to complete their journey to the sea. It will also allow project operators to mix warmer surface water with cooler water from the bottom of the reservoir to improve conditions for fish in the lower Deschutes River.
The facility was originally slated for completion and testing last spring but was delayed when the vertical flow conduit separated before final assembly in April — leaving portions of it on the bottom of Lake Billy Chinook. The conduit is the huge pipe that connects the fish collection and transfer facility on the surface of Lake Billy Chinook with the powerhouse intake structure on the bottom of the reservoir.
PGE staff worked with project contractors and outside experts to conduct a root cause analysis and revise construction procedures before recommencing construction this fall.
