Taking advantage of the hydrocombine design of Wells Dam, Douglas PUD’s Juvenile Fish Bypass System safely guides juvenile salmonids over Wells Dam through modified spillways, avoiding turbine passage routes
Douglas PUD developed the Wells Dam Juvenile Fish Bypass System (JFBS) in the
late 1980s to provide safe passage for juvenile salmon and steelhead. The JFBS capitalizes on the design of Wells Dam, with eleven spillways situated directly over ten turbine intakes, relying on the bulk flow to the turbines to attract fish to five modified spillways.
The five JFBS entrances are spaced evenly across the face of the dam. Juvenile fish migrate near the water surface, and most fish pass Wells Dam through these modified spillways rather than through turbine intakes 70 feet below the surface.
The guidance efficiency (a measure of the percentage of fish that pass via a bypass route) of the Wells JFBS is the highest of any hydroproject on the Columbia River hydrosystem: 92% for yearling Chinook
and steelhead, 95.3% for sockeye smolts, and 96.2% for subyearling Chinook.