Columbia Basin Performance Measures

Adult Passage Exposure Results

Adult Chinook Query Parameters

Year	2025
Project	Bonneville
River Parameter	Temperature Tailrace
Critical Temperature Tailrace Value	15 °C
Calculate Exposure	Above Critical Value
River Parameter Data Fill	No
Query Dates	3/15 - 6/15

Total Run Period (Mar 15 - Jun 15)

Total Number of Fish Observed	146061
Percent of Total Run Analyzed [Number Observed]	100 % [146061]
Temperature Tailrace Exposure Index	13.68 °C
Percent of Fish Exposed [Number Exposed]	21.5 % [31526]
Number of Days Fish Exposed	20

Middle 80% of Run Period (Apr 26 - Jun 8)

Number of Fish Observed	121376
Percent of Middle 80% of Run Analyzed [Number Observed]	100 % [121376]
Temperature Tailrace Exposure Index	13.49 °C
Percent of Fish Exposed [Number Exposed]	15.2 % [18536]
Number of Days Fish Exposed	13

Middle 50% of Run Period (May 2 - May 23)

Number of Fish Observed	77203
Percent of Middle 50% of Run Analyzed [Number Observed]	100 % [77203]
Temperature Tailrace Exposure Index	13.17 °C
Percent of Fish Exposed [Number Exposed]	0 % [0]
Number of Days Fish Exposed	0

Run Dates

First Day of Run	Mar 15
5% of Run passed	Apr 23
10% of Run passed	Apr 26
50% of Run passed	May 8
90% of Run passed	Jun 8
95% of Run passed	Jun 11
Last Day of Run	Jun 15

Date(s) When Temperature Tailrace Crosses 15 °C

May 27