Limiting Factors



Intermountain Province

Sanpoil Subbasin 408

KOKANEE
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Dam or Hydropower Facility Management; Urbanization Migration Impediments Juveniles, adults Chief Joseph and Grand Coulee dams, both of which lack fish passage facilities, prevent upriver migrations and negatively impact downriver migration. Resident fish emigrating downstream are entrained and are unable to return to the subbasin. Major barriers (i.e., culverts) exist along State Highway 21 blocking most Westside streams to fish migration except the West Fork of the San Poil River and the North and South Nanamkin creeks.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Riparian Degradation Juveniles, adults Embedded substrate and reduced habitat complexity, due to anthropogenic activities, limits native salmonid populations.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Channel stability is decreased because of cleared riparian areas.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Riparian Degradation All Decreased channel stability from cleared riparian areas and high road densities combine to create fine sediment issues throughout the subbasin.
Water Quality Temperature; Oxygen -- Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Water: Storage or Withdrawal All Oxygen and temperature conditions are impaired throughout the subbasin due to forest management practices and water diversions.
Water Quantity Decreased Water Quantity -- Agricultural Practices; Forest Management Water: Storage or Withdrawal All Low flows exist throughout the subbasin due to forest management practices and water diversions.
REDBAND TROUT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Biological Viability Criteria Diversity -- Fishery Management Species Introduction Adults Non-native rainbow trout releases lead to hybridization with native redband trout.
Habitat Quantity and Quality Access and Availability Freshwater-Instream Dam or Hydropower Facility Management; Urbanization Migration Impediments Juveniles, adults Chief Joseph and Grand Coulee dams, both of which lack fish passage facilities, prevent upriver migrations and negatively impact downriver migration. Resident fish emigrating downstream are entrained and are unable to return to the subbasin. Major barriers (i.e., culverts) exist along State Highway 21 blocking most Westside streams to fish migration except the West Fork of the San Poil River and the North and South Nanamkin creeks.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Riparian Degradation Juveniles, adults Embedded substrate and reduced habitat complexity, due to anthropogenic activities, limits native salmonid populations.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Channel stability is decreased because of cleared riparian areas.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Riparian Degradation All Decreased channel stability from cleared riparian areas and high road densities combine to create fine sediment issues throughout the subbasin.
Water Quality Temperature; Oxygen -- Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Water: Storage or Withdrawal All Oxygen and temperature conditions are impaired throughout the subbasin due to forest management practices and water diversions.
Water Quantity Decreased Water Quantity -- Agricultural Practices; Forest Management Water: Storage or Withdrawal All Low flows exist throughout the subbasin due to forest management practices and water diversions.