The fish-friendly design of the Wells Hydroelectric Project facilitated the achievement of the project survival standards specified by the Wells Habitat Conservation Plan (HCP). The relevant standards for juveniles are 93% Measured Project Survival, and 95% Calculated Dam Passage Survival. Project survival includes survival through the reservoir, dam, and tailrace.

Calculated Dam Passage Survival (Based on Bypass Guidance Efficiency)

Yearling Sockeye  >95%

Subyearling Chinook   >95%

Wells Bypass Guidance Efficiency:

Yearling Chinook  92.0%

Yearling Steelhead  92.0%

Yearling Sockeye  95.3%

Subyearling Chinook  96.2%

Measured Juvenile Project Survival:

1998: Methow Yearling  Chinook   99.7%

1999: Methow Yearling Steelhead   94.3%

2000: Methow Yearling  Steelhead  94.6%

2010: Methow & Okanogan Yearling Chinook  96.4%

2020: Methow & Okanogan Yearling Chinook  95.2%

5-Year Average for Yearling Spring Migrants  96.0%