Scientific Investigations Report 2006–5230
U.S. GEOLOGICAL SURVEY
Scientific Investigations Report 2006–5230
Table 3. Summary of habitat and hydrologic measurements for lower Big Boulder Creek (BB1), upper Salmon River Basin, Idaho, 2005.
[Values presented in cubic feet per second. Discharge passage criteria: Passage criteria taken from Thompson (1972) and Scott and others (1981); both width criteria must be met to ensure passage. Channel width: Represents measurements at three transects. Discharge estimates: Based on regional regression equations using basin and climatic characteristics (Hortness and Berenbrock, 2001); Q.xx, daily discharge exceeded xx percent of the time during the specified month; Qa, mean annual discharge. Abbreviations: WUA; weighted usable area; WUA optimum discharge estimates were based on PHABSIM (Physical Habitat Simulation) model output; EPT, Ephemeroptera, Plecoptera, and Trichoptera taxa; ND, not determined]
Lifestage | Discharge required for maximum WUA | Discharge required for adult salmonid passage 0.6-foot depth criterion | Discharge estimates | |||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Channel width | ||||||||||||||||||||
Bull trout | Chinook salmon | Steelhead trout | EPT invertebrates | Greater than 25 percent (total) | Greater than 10 percent (contiguous) | July | August | September | ||||||||||||
Q.80 | Q.50 | Q.20 | Q.80 | Q.50 | Q.20 | Q.80 | Q.50 | Q.20 | Qa | |||||||||||
Adult | 24 | 39 | 39 | ND | 27, 18, 21 | 27, 15, 15 | 18.2 | 32.1 | 52.0 | 10.2 | 15.1 | 23.2 | 7.6 | 10.7 | 15.1 | 15.2 | ||||
Spawning | 33 | 39 | 39 | ND | ND | ND | ||||||||||||||
Immature | ND | ND | ND | 24 | ND | ND |