Columbia Basin Performance Measures

Adult Passage Exposure Results

Adult Steelhead Query Parameters

Year	2025
Project	Lower Monumental
River Parameter	Temperature Tailrace
Critical Temperature Tailrace Value	15 °C
Calculate Exposure	Above Critical Value
River Parameter Data Fill	No
Query Dates	1/1 - 12/31

Total Run Period (Apr 1 - Oct 31)

Total Number of Fish Observed	75582
Percent of Total Run Analyzed [Number Observed]	100 % [75582]
Temperature Tailrace Exposure Index	19.2 °C
Percent of Fish Exposed [Number Exposed]	98.4 % [74409]
Number of Days Fish Exposed	144

Middle 80% of Run Period (Sep 6 - Oct 20)

Number of Fish Observed	61921
Percent of Middle 80% of Run Analyzed [Number Observed]	100 % [61921]
Temperature Tailrace Exposure Index	19.43 °C
Percent of Fish Exposed [Number Exposed]	100 % [61921]
Number of Days Fish Exposed	45

Middle 50% of Run Period (Sep 21 - Oct 11)

Number of Fish Observed	39658
Percent of Middle 50% of Run Analyzed [Number Observed]	100 % [39658]
Temperature Tailrace Exposure Index	19.71 °C
Percent of Fish Exposed [Number Exposed]	100 % [39658]
Number of Days Fish Exposed	21

Run Dates

First Day of Run	Apr 1
5% of Run passed	Jul 29
10% of Run passed	Sep 6
50% of Run passed	Oct 1
90% of Run passed	Oct 20
95% of Run passed	Oct 24
Last Day of Run	Oct 31

Date(s) When Temperature Tailrace Crosses 15 °C

May 31

Oct 30