Limiting Factors



Columbia Cascade Province

Columbia Upper Middle Subbasin

RAINBOW TROUT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices Riparian Degradation; Bank Destabilization Juveniles Steep, sparsely vegetated shorelines limit rearing habitat.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management Predators: Fish; Predators: Avian Juveniles Introductions of non-native predator fishes as well as an increase in populations of indigenous predator fish species, and the immigration of diving birds are potentially limiting survival of juvenile salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Dam or Hydropower Facility Management Sediment: Retention Adult spawners Smoothing of the hydrograph and lack of significant reservoir fluctuations has resulted in an increased amount of fine sediment in the lower portions of the reservoirs thus concentrating anadromous salmonid spawning to the upper reaches of the reservoirs.
Water Quality Oxygen -- Dam or Hydropower Facility Management Water: Temperature and Gas Alteration; Pollution and Contamination Juveniles Occasionally total dissolved gas levels exceed maximum allowed levels during periods of high run-off. Mean annual phosphate concentrations often exceed levels that could stimulate algal blooms.
Water Quantity Altered Flow Timing -- Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Hydrologic Cycle Alteration Juveniles Operation of Wanapum, Rock Island, Rocky Reach, Wells, and Chief Joseph dams results in rapid flushing rates and no thermal stratification during the summer. Productivity is limited due to rapid flushing rates, cold temperatures, and lack of shallow water areas. Food that is available in the reservoirs typically provides lower amounts of energy than found in free-flowing areas such as the Hanford Reach.
SPRING CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices Riparian Degradation; Bank Destabilization Juveniles Steep, sparsely vegetated shorelines limit rearing habitat.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Juveniles and adults must pass eight mainstem dams during migration.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management Predators: Fish; Predators: Avian Juveniles Introductions of non-native predator fishes as well as an increase in populations of indigenous predator fish species, and the immigration of diving birds are potentially limiting survival of juvenile salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Dam or Hydropower Facility Management Sediment: Retention Adult spawners Smoothing of the hydrograph and lack of significant reservoir fluctuations has resulted in an increased amount of fine sediment in the lower portions of the reservoirs thus concentrating anadromous salmonid spawning to the upper reaches of the reservoirs.
Water Quality Oxygen -- Dam or Hydropower Facility Management Water: Temperature and Gas Alteration; Pollution and Contamination Juveniles Occasionally total dissolved gas levels exceed maximum allowed levels during periods of high run-off. Mean annual phosphate concentrations often exceed levels that could stimulate algal blooms.
Water Quantity Altered Flow Timing -- Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Hydrologic Cycle Alteration Juveniles Operation of Wanapum, Rock Island, Rocky Reach, Wells, and Chief Joseph dams results in rapid flushing rates and no thermal stratification during the summer. Productivity is limited due to rapid flushing rates, cold temperatures, and lack of shallow water areas. Food that is available in the reservoirs typically provides lower amounts of energy than found in free-flowing areas such as the Hanford Reach.
SUMMER CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Juveniles and adults must pass eight mainstem dams during migration.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management Predators: Fish; Predators: Avian Juveniles Introductions of non-native predator fishes as well as an increase in populations of indigenous predator fish species, and the immigration of diving birds are potentially limiting survival of juvenile salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Dam or Hydropower Facility Management Sediment: Retention Adult spawners Smoothing of the hydrograph and lack of significant reservoir fluctuations has resulted in an increased amount of fine sediment in the lower portions of the reservoirs thus concentrating anadromous salmonid spawning to the upper reaches of the reservoirs.
Water Quality Oxygen -- Dam or Hydropower Facility Management Water: Temperature and Gas Alteration; Pollution and Contamination Juveniles Occasionally total dissolved gas levels exceed maximum allowed levels during periods of high run-off. Mean annual phosphate concentrations often exceed levels that could stimulate algal blooms.
Water Quantity Altered Flow Timing -- Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Hydrologic Cycle Alteration Juveniles Operation of Wanapum, Rock Island, Rocky Reach, Wells, and Chief Joseph dams results in rapid flushing rates and no thermal stratification during the summer. Productivity is limited due to rapid flushing rates, cold temperatures, and lack of shallow water areas. Food that is available in the reservoirs typically provides lower amounts of energy than found in free-flowing areas such as the Hanford Reach.
SUMMER STEELHEAD
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Juveniles and adults must pass eight mainstem dams during migration.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management Predators: Fish; Predators: Avian Juveniles Introductions of non-native predator fishes as well as an increase in populations of indigenous predator fish species, and the immigration of diving birds are potentially limiting survival of juvenile salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Dam or Hydropower Facility Management Sediment: Retention Adult spawners Smoothing of the hydrograph and lack of significant reservoir fluctuations has resulted in an increased amount of fine sediment in the lower portions of the reservoirs thus concentrating anadromous salmonid spawning to the upper reaches of the reservoirs.
Water Quality Oxygen -- Dam or Hydropower Facility Management Water: Temperature and Gas Alteration; Pollution and Contamination Juveniles Occasionally total dissolved gas levels exceed maximum allowed levels during periods of high run-off. Mean annual phosphate concentrations often exceed levels that could stimulate algal blooms.
Water Quantity Altered Flow Timing -- Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Hydrologic Cycle Alteration Juveniles Operation of Wanapum, Rock Island, Rocky Reach, Wells, and Chief Joseph dams results in rapid flushing rates and no thermal stratification during the summer. Productivity is limited due to rapid flushing rates, cold temperatures, and lack of shallow water areas. Food that is available in the reservoirs typically provides lower amounts of energy than found in free-flowing areas such as the Hanford Reach.

Entiat Subbasin 402

BULL TROUT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Food Competition -- Species Management Species Introduction Juveniles, adults Introduction of brook trout threatens bull trout through competition and hybridization.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Instream-habitat diversity is low with few pools, glides, pocket waters, or large woody debris. Loss of large pools below Mad River confluence.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Road densities are high and in close proximity to streams. Past logging and road building affects tributary riparian condition in Preston and Brennegan creeks.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Illegal Harvest Adults Poaching levels continue to be substantial.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles, adults Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Species Management Species Introduction Juveniles, adults Walleye and smallmouth bass prey on salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Erosion in upland areas in Fox, McCRee, Brenegan, Preston, and Mud creeks, Crum Canyon and the mainstem Entiat between Fox and Stormy creeks contribute to the percent fines in the lower Entiat. High road density, a high number of road miles in the riparian corridor, and road maintenance practices contribute to increased sediment delivery.
Water Quantity Decreased Water Quantity; Altered Flow Timing -- Dam or Hydropower Facility Management Water: Storage or Withdrawal All Low flows are a natural occurrence within the subbasin limiting production of some salmonid species.
COHO
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Decreased Water Quantity; Morphological Changes Freshwater - Floodplain Agricultural Practices; Urbanization Diking; Impervious Surfaces Juveniles, adults Most of the mainstem Entiat has been channelized and flood control measures have been implemented. The connectivity of the floodplain from the mouth of Mad River to Pine Flats Campground (river mile 4) has been reduced by orchards, Ardenvoir, County Road 119, and Forest Service Road 5700.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Road densities are high and in close proximity to streams. Past logging and road building affects tributary riparian condition in Preston and Brennegan creeks. In the lower mainstem Mad River, from the mouth to Pine Flats Campground, there is a loss of riparian connectivity and function.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Low stream channel complexity is the primary limitation to productivity of salmonids in the lower 12.4 miles. Stream sinuosity is low, with few point bars for gravel accumulation. Instream-habitat diversity is low with few pools, glides, pocket waters, or large woody debris. Loss of large pools below Mad River confluence. Large woody debris is lacking throughout the middle section of the Entiat River and Lower Mad River. Lack of overwintering juvenile habitat, especially in the Lower Mad River, limits productivity and distribution.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest; Illegal Harvest Adults Coho are subject to ocean and fresh water harvest. Poaching levels continue to be substantial.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Juveniles and adults must pass eight mainstem dams during migration.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish Juveniles Walleye and smallmouth bass prey on salmonids.
Water Quantity Decreased Water Quantity; Increased Water Quantity -- Dam or Hydropower Facility Management; Urbanization Water: Storage or Withdrawal; Impervious Surfaces Juveniles Low flows are a natural occurrence within the subbasin limiting production of some salmonid species. Irrigation may exacerbate poor conditions in the Lower Entiat. In-stream flow is a concern in the Lower Entiat from river mile 0-10. The road from Pine Flat Campground (Mad River) to the mouth constricts the channel increasing the flow velocities.
PACIFIC LAMPREY
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Migration Impediments Juveniles, adults Complete or partial barriers exist on Brenegan, Preston, Stormy, Mud, and Tillicum creeks. Eighteen fish passage barriers exist from Potato Moraine to Entiat Flats.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Juveniles Historical complex habitats have been modified through channelization, diking, development and other practices.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Juveniles and adults must pass eight mainstem dams during migration.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish Juveniles Walleye and smallmouth bass prey on juvenile lamprey
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All High road density, a high number of road miles in the riparian corridor, and road maintenance practices contribute to increased sediment delivery.
Water Quality Temperature -- Water Management Water: Temperature and Gas Alteration Winter low temperatures and formation of anchor ice in the lower mainstem Entiat and Mad rivers is problematic
Water Quantity Decreased Water Quantity; Increased Water Quantity -- Dam or Hydropower Facility Management; Urbanization Water: Storage or Withdrawal; Impervious Surfaces Juveniles Low flows are a natural occurrence within the subbasin limiting production of some salmonid species. Irrigation may exacerbate poor conditions in the Lower Entiat. In-stream flow is a concern in the Lower Entiat from river mile 0-10. The road from Pine Flat Campground (Mad River) to the mouth constricts the channel increasing the flow velocities.
SPRING CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Migration Impediments Juveniles, adults Complete or partial barriers exist on Brenegan, Preston, Stormy, Mud, and Tillicum creeks. Eighteen fish passage barriers exist from Potato Moraine to Entiate Flats.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Decreased Water Quantity; Morphological Changes Freshwater - Floodplain Agricultural Practices; Urbanization Diking; Impervious Surfaces Juveniles, adults Most of the mainstem Entiat has been channelized and flood control measures have been implemented. The connectivity of the floodplain from the mouth of Mad River to Pine Flats Campground (river mile 4) has been reduced by orchards, Ardenvoir, County Road 119, and Forest Service Road 5700.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Road densities are high and in close proximity to streams. Past logging and road building affects tributary riparian condition in Preston and Brennegan creeks. In the lower mainstem Mad River, from the mouth to Pine Flats Campground, there is a loss of riparian connectivity and function.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Low stream channel complexity is the primary limitation to productivity of salmonids in the lower 12.4 miles. Stream sinuosity is low, with few point bars for gravel accumulation. Instream-habitat diversity is low with few pools, glides, pocket waters, or large woody debris. Loss of large pools below Mad River confluence. Large woody debris is lacking throughout the middle section of the Entiat River and Lower Mad River. Lack of overwintering juvenile habitat, especially in the Lower Mad River, limits productivity and distribution.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest; Illegal Harvest Adults Spring Chinook are subject to fresh water harvest. Poaching levels continue to be substantial.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Juveniles and adults must pass eight mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles Walleye and smallmouth bass prey on salmonids. Avian and pinniped predation are concerns.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All High road density, a high number of road miles in the riparian corridor, and road maintenance practices contribute to increased sediment delivery.
Water Quality Temperature -- Water Management Water: Temperature and Gas Alteration Exceedence of state water quality standards for temperature, from July-September, in the Lower Entiat River. Winter low temperatures and formation of anchor ice in the lower mainstem Entiat and Mad rivers is problematic. Cold winter water temperatures affect egg incubation survival, time of emergence, and winter rearing habitat in the lower Entiat.
Water Quantity Decreased Water Quantity; Increased Water Quantity -- Dam or Hydropower Facility Management; Urbanization Water: Storage or Withdrawal; Impervious Surfaces Juveniles Low flows are a natural occurrence within the subbasin limiting production of some salmonid species. Irrigation may exacerbate poor conditions in the Lower Entiat. In-stream flow is a concern in the Lower Entiat from river mile 0-10. The road from Pine Flat Campground (Mad River) to the mouth constricts the channel increasing the flow velocities.
SUMMER STEELHEAD
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Migration Impediments Juveniles, adults Complete or partial barriers exist on Brenegan, Preston, Stormy, Mud, and Tillicum creeks. Eighteen fish passage barriers exist from Potato Moraine to Entiate Flats.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Decreased Water Quantity; Morphological Changes Freshwater - Floodplain Agricultural Practices; Urbanization Diking; Impervious Surfaces Juveniles, adults Most of the mainstem Entiat has been channelized and flood control measures have been implemented. The connectivity of the floodplain from the mouth of Mad River to Pine Flats Campground (river mile 4) has been reduced by orchards, Ardenvoir, County Road 119, and Forest Service Road 5700.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Road densities are high and in close proximity to streams. Past logging and road building affects tributary riparian condition in Preston and Brennegan creeks. In the lower mainstem Mad River, from the mouth to Pine Flats Campground, there is a loss of riparian connectivity and function.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Low stream channel complexity is the primary limitation to productivity of salmonids in the lower 12.4 miles. Stream sinuosity is low, with few point bars for gravel accumulation. Instream-habitat diversity is low with few pools, glides, pocket waters, or large woody debris. Loss of large pools below Mad River confluence. Large woody debris is lacking throughout the middle section of the Entiat River and Lower Mad River. Lack of overwintering juvenile habitat, especially in the Lower Mad River, limits productivity and distribution.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest; Illegal Harvest Adults Steelhead are subject to fresh water harvest. Poaching levels continue to be substantial.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass eight mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles Avian and pinniped predation are concerns. Walleye and smallmouth bass prey on salmonids
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Sediment and cobble embeddedness problematic in the Lower Entiat River. Erosion in upland areas in Fox, McCRee, Brenegan, Preston, and Mud creeks, Crum Canyon and the mainstem Entiat between Fox and Stormy creeks contribute to the percent fines in the lower Entiat. High road density, a high number of road miles in the riparian corridor, and road maintenance practices contribute to increased sediment delivery
Water Quality Temperature -- Water Management Water: Temperature and Gas Alteration All Exceedence of state water quality standards for temperature, from July-September, in the Lower Entiat River. Cold winter water temperatures affect egg incubation survival, time of emergence, and winter rearing habitat in the lower Entiat. Winter low temperatures and formation of anchor ice in the lower mainstem Entiat and Mad rivers is problematic
Water Quantity Decreased Water Quantity; Increased Water Quantity -- Dam or Hydropower Facility Management; Urbanization Water: Storage or Withdrawal; Impervious Surfaces Juveniles Low flows are a natural occurrence within the subbasin limiting production of some salmonid species. Irrigation may exacerbate poor conditions in the Lower Entiat. In-stream flow is a concern in the Lower Entiat from river mile 0-10. The road from Pine Flat Campground (Mad River) to the mouth constricts the channel increasing the flow velocities.
SUMMER/FALL CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Decreased Water Quantity; Morphological Changes Freshwater - Floodplain Agricultural Practices; Urbanization Diking; Impervious Surfaces Juveniles, adults Most of the mainstem Entiat has been channelized and flood control measures have been implemented. The connectivity of the floodplain from the mouth of Mad River to Pine Flats Campground (river mile 4) has been reduced by orchards, Ardenvoir, County Road 119, and Forest Service Road 5700.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Road densities are high and in close proximity to streams. Past logging and road building affects tributary riparian condition in Preston and Brennegan creeks. In the lower mainstem Mad River, from the mouth to Pine Flats Campground, there is a loss of riparian connectivity and function.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Low stream channel complexity is the primary limitation to productivity of salmonids in the lower 12.4 miles. Stream sinuosity is low, with few point bars for gravel accumulation. Instream-habitat diversity is low with few pools, glides, pocket waters, or large woody debris. Loss of large pools below Mad River confluence. Large woody debris is lacking throughout the middle section of the Entiat River and Lower Mad River. Lack of overwintering juvenile habitat, especially in the Lower Mad River, limits productivity and distribution.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest; Illegal Harvest Adults Steelhead are subject to fresh water harvest. Poaching levels continue to be substantial.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass eight mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles Avian and pinniped predation are concerns. Walleye and smallmouth bass prey on salmonids
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Sediment and cobble embeddedness problematic in the Lower Entiat River. Erosion in upland areas in Fox, McCRee, Brenegan, Preston, and Mud creeks, Crum Canyon and the mainstem Entiat between Fox and Stormy creeks contribute to the percent fines in the lower Entiat. High road density, a high number of road miles in the riparian corridor, and road maintenance practices contribute to increased sediment delivery
Water Quality Temperature -- Water Management Water: Temperature and Gas Alteration All Exceedence of state water quality standards for temperature, from July-September, in the Lower Entiat River. Cold winter water temperatures affect egg incubation survival, time of emergence, and winter rearing habitat in the lower Entiat. Winter low temperatures and formation of anchor ice in the lower mainstem Entiat and Mad rivers is problematic
Water Quantity Decreased Water Quantity; Increased Water Quantity -- Dam or Hydropower Facility Management; Urbanization Water: Storage or Withdrawal; Impervious Surfaces Juveniles Low flows are a natural occurrence within the subbasin limiting production of some salmonid species. Irrigation may exacerbate poor conditions in the Lower Entiat. In-stream flow is a concern in the Lower Entiat from river mile 0-10. The road from Pine Flat Campground (Mad River) to the mouth constricts the channel increasing the flow velocities.
WESTSLOPE CUTTHROAT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Instream-habitat diversity is low with few pools, glides, pocket waters, or large woody debris. Loss of large pools below Mad River confluence.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Road densities are high and in close proximity to streams. Past logging and road building affects tributary riparian condition in Preston and Brennegan creeks.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Illegal Harvest Adults Poaching levels continue to be substantial.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles, adults Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Species Management Species Introduction Juveniles, adults Walleye and smallmouth bass prey on salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Erosion in upland areas in Fox, McCRee, Brenegan, Preston, and Mud creeks, Crum Canyon and the mainstem Entiat between Fox and Stormy creeks contribute to the percent fines in the lower Entiat. High road density, a high number of road miles in the riparian corridor, and road maintenance practices contribute to increased sediment delivery.
Water Quality Temperature -- Water Management Water: Temperature and Gas Alteration All Exceedence of state water quality standards for temperature, from July-September, in the Lower Entiat River. Cold winter water temperatures affect egg incubation survival, time of emergence, and winter rearing habitat in the lower Entiat. Winter low temperatures and formation of anchor ice in the lower mainstem Entiat and Mad rivers is problematic
Water Quantity Decreased Water Quantity; Altered Flow Timing -- Dam or Hydropower Facility Management Water: Storage or Withdrawal All Low flows are a natural occurrence within the subbasin limiting production of some salmonid species.

Lake Chelan Subbasin 403

Bull Trout
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Food Altered Primary Productivity -- Water Management Water: Nutrient Alteration All Levels of nitrates, chlorophyll a, zooplankton, and benthic organisms are low, especially in the Lucerne Basin. The productivity of the lake is also affected by elevated bacterial levels and pesticide residues.
Food Competition -- Species Management Species Introduction Juveniles, adults Competition between native fish species and introduced game fish has reduced or eliminated native fish populations.
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Dam or Hydropower Facility Management Migration Impediments Adults Sediment deposits at the mouths of some tributaries have created barriers to spawning areas. Fish, Safety, Prince, Gold, Grade, Mitchell, and Rail Road creeks contain sediment barriers that block passage of during upstream spawning migrations.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management Riparian Degradation; Bank Destabilization Juveniles, adults Large woody debris has been removed limiting cover and reducing in-stream complexity. Tributaries to Lake Chelan (from Manson to Stehekin) lack appropriately sized gravel for trout spawning as well as large woody debris.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Dam or Hydropower Facility Management Riparian Degradation Juveniles, adults Vegetation is limited along the Lake Chelan shoreline due to the steep-sided configuration of the drainage, the thin, rocky soils, and heavy wave action. Riparian and wetland habitat have been removed or filled near the mouth of the Stehekin River. Grazing and lake level fluctuations have reduced riparian habitat. Large trees, snags, and woody debris are limited. From Mitchell Creek down the lake, large trees and mid– to low-level shrubs and forbs/grasses are limited in numbers. Most tributaries (Grade, Mitchell, Box, Big, Bear, Prince, and Fish) have narrow, steep-walled drainages, deeply-incised channels, narrow bands of riparian vegetation alongside the streams, and a lack of large woody debris.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Populations are subject to high levels of legal harvest.
Water Quality Oxygen; pH; -- Water Management Water: Temperature and Gas Alteration; All First Creek and the lower Chelan River (Chelan Falls and Hatchery) are on the EPA’s 303d list for impaired water quality due to dissolved oxygen. Mitchell Creek was listed for irregularities in pH.
KOKANEE
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Food Altered Primary Productivity -- Water Management Water: Nutrient Alteration All Levels of nitrates, chlorophyll a, zooplankton, and benthic organisms are low, especially in the Lucerne Basin. The productivity of the lake is also affected by elevated bacterial levels and pesticide residues.
Instantaneous Mortality Predation -- Species Management Species Introduction Juveniles, adults Competition between native fish species and introduced game fish has reduced or eliminated native fish populations.
Water Quality Oxygen; pH; -- Water Management Water: Temperature and Gas Alteration; All First Creek and the lower Chelan River (Chelan Falls and Hatchery) are on the EPA’s 303d list for impaired water quality due to dissolved oxygen. Mitchell Creek was listed for irregularities in pH.
WESTSLOPE CUTTHROAT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Food Altered Primary Productivity -- Water Management Water: Nutrient Alteration All Levels of nitrates, chlorophyll a, zooplankton, and benthic organisms are low, especially in the Lucerne Basin. The productivity of the lake is also affected by elevated bacterial levels and pesticide residues.
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Dam or Hydropower Facility Management Migration Impediments Adults Sediment deposits at the mouths of some tributaries have created barriers to spawning areas. Fish, Safety, Prince, Gold, Grade, Mitchell, and Rail Road creeks contain sediment barriers that block passage of during upstream spawning migrations.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management Riparian Degradation; Bank Destabilization Juveniles, adults Large woody debris has been removed limiting cover and reducing in-stream complexity. Tributaries to Lake Chelan (from Manson to Stehekin) lack appropriately sized gravel for trout spawning as well as large woody debris.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Dam or Hydropower Facility Management Riparian Degradation Juveniles, adults Vegetation is limited along the Lake Chelan shoreline due to the steep-sided configuration of the drainage, the thin, rocky soils, and heavy wave action. Riparian and wetland habitat have been removed or filled near the mouth of the Stehekin River. Grazing and lake level fluctuations have reduced riparian habitat. Large trees, snags, and woody debris are limited. From Mitchell Creek down the lake, large trees and mid– to low-level shrubs and forbs/grasses are limited in numbers. Most tributaries (Grade, Mitchell, Box, Big, Bear, Prince, and Fish) have narrow, steep-walled drainages, deeply-incised channels, narrow bands of riparian vegetation alongside the streams, and a lack of large woody debris.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Populations are subject to high levels of legal harvest.
Instantaneous Mortality Predation -- Species Management Species Introduction Juveniles, adults Competition between native fish species and introduced game fish has reduced or eliminated native fish populations.
Water Quality Oxygen; pH; -- Water Management Water: Temperature and Gas Alteration; All First Creek and the lower Chelan River (Chelan Falls and Hatchery) are on the EPA’s 303d list for impaired water quality due to dissolved oxygen. Mitchell Creek was listed for irregularities in pH.

Methow Subbasin 402, 404

Bull Trout
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Food Competition -- Species Management Species Introduction Juveniles, adults Introduction of brook trout threatens bull trout through competition and hybridization.
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Two passage barriers (culverts) exist in the lower 3.5 miles of the Black Canyon/Squaw Creek. Methow Valley Irrigation District canal diversion and culverts are impediments in the Lower Twisp. Flow diversions are present in the Lower Chewuch River as well as culverts in Cub and Little Boulder creeks (Lower Chewuch River). A road confinement velocity barrier exists in Eightmile Creek.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris exists throughout the subbasin as well as high embeddedness in spawning habitat. There has been a loss of quality pools and large woody debris in Little Boulder Creek and the gorge in Goat Creek.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Loss of riparian vegetation is prevalent throughout the subbasin.
Instantaneous Mortality Predation -- Species Management Species Introduction Juveniles, adults Walleye and smallmouth bass prey on salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Increased sediment load and high percentage of fines exists in the depositional areas. Increased sediment load below Buttermilk Creek (Lower Twisp) is problematic.
Water Quantity Increased Water Quantity; Decreased Water Quantity -- Forest Management Water: Storage or Withdrawal Juveniles, adults Increased peak flows and increased flashy flows exist due to fires in the headwaters. Low flows persist due to natural losing at river mile 0-4.3 on Wolf Creek.
Coho
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Decreased Water Quantity; Morphological Changes Freshwater - Floodplain Agricultural Practices; Urbanization Diking; Impervious Surfaces; Riparian Degradation Juveniles Loss of connection to the floodplain due to roads and riprap in the first reach of Early Winters Creek and Lost River. High road densities exist in Little Bridge, Poorman, and Buttermilk creeks. Loss of connection to the floodplain in the lower 800 feet of Wolf Creek and the loss of riparian vegetation in the lower mile of Goat Creek/Little Boulder limit productivity.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles Loss of riparian vegetation is prevalent throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles Lack of large woody debris exists throughout the subbasin as well as high embeddedness in spawning habitat. There has been a loss of quality pools and large woody debris in Little Boulder Creek and the gorge in Goat Creek.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Coho are subject to ocean and fresh water harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass nine mainstem dams during migration.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Increased sediment load and high percentage of fines exists in the depositional areas. Increased sediment load below Buttermilk Creek (Lower Twisp) is problematic.
SPRING CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Two passage barriers (culverts) exist in the lower 3.5 miles of the Black Canyon/Squaw Creek. Methow Valley Irrigation District canal diversion and culverts are impediments in the Lower Twisp. Flow diversions are present in the Lower Chewuch River as well as culverts in Cub and Little Boulder creeks (Lower Chewuch River). A road confinement velocity barrier exists in Eightmile Creek.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Decreased Water Quantity; Morphological Changes Freshwater - Floodplain Agricultural Practices; Urbanization Diking; Impervious Surfaces; Riparian Degradation Juveniles Loss of connection to the floodplain due to roads and riprap in the first reach of Early Winters Creek and Lost River. High road densities exist in Little Bridge, Poorman, and Buttermilk creeks. Loss of connection to the floodplain in the lower 800 feet of Wolf Creek and the loss of riparian vegetation in the lower mile of Goat Creek/Little Boulder limit productivity.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles Loss of riparian vegetation is prevalent throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles Lack of large woody debris exists throughout the subbasin as well as high embeddedness in spawning habitat. There has been a loss of quality pools and large woody debris in Little Boulder Creek and the gorge in Goat Creek.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Spring Chinook are subject to fresh water harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass nine mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles Avian and pinniped predation are concerns. Walleye and smallmouth bass prey on salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; Juveniles Increased sediment load and high percentage of fines exists in the depositional areas. Water temperatures limit spring Chinook spawning and incubation from river mile 0-4 in the Lower Twisp. Increased sediment load below Buttermilk Creek (Lower Twisp) is problematic.
Summer Chinook
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Two passage barriers (culverts) exist in the lower 3.5 miles of the Black Canyon/Squaw Creek. Methow Valley Irrigation District canal diversion and culverts are impediments in the Lower Twisp. Flow diversions are present in the Lower Chewuch River as well as culverts in Cub and Little Boulder creeks (Lower Chewuch River). A road confinement velocity barrier exists in Eightmile Creek.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Decreased Water Quantity; Morphological Changes Freshwater - Floodplain Agricultural Practices; Urbanization Diking; Impervious Surfaces; Riparian Degradation Juveniles Loss of connection to the floodplain due to roads and riprap in the first reach of Early Winters Creek and Lost River. High road densities exist in Little Bridge, Poorman, and Buttermilk creeks. Loss of connection to the floodplain in the lower 800 feet of Wolf Creek and the loss of riparian vegetation in the lower mile of Goat Creek/Little Boulder limit productivity.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles Loss of riparian vegetation is prevalent throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles Lack of large woody debris exists throughout the subbasin as well as high embeddedness in spawning habitat. There has been a loss of quality pools and large woody debris in Little Boulder Creek and the gorge in Goat Creek.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Spring Chinook are subject to fresh water harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass nine mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles Avian and pinniped predation are concerns. Walleye and smallmouth bass prey on salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; Juveniles Increased sediment load and high percentage of fines exists in the depositional areas. Water temperatures limit spring Chinook spawning and incubation from river mile 0-4 in the Lower Twisp. Increased sediment load below Buttermilk Creek (Lower Twisp) is problematic.
SUMMER STEELHEAD
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Two passage barriers (culverts) exist in the lower 3.5 miles of the Black Canyon/Squaw Creek. Methow Valley Irrigation District canal diversion and culverts are impediments in the Lower Twisp. Flow diversions are present in the Lower Chewuch River as well as culverts in Cub and Little Boulder creeks (Lower Chewuch River). A road confinement velocity barrier exists in Eightmile Creek.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Decreased Water Quantity; Morphological Changes Freshwater - Floodplain Agricultural Practices; Urbanization Diking; Impervious Surfaces; Riparian Degradation Juveniles Loss of connection to the floodplain due to roads and riprap in the first reach of Early Winters Creek and Lost River. High road densities exist in Little Bridge, Poorman, and Buttermilk creeks. Loss of connection to the floodplain in the lower 800 feet of Wolf Creek and the loss of riparian vegetation in the lower mile of Goat Creek/Little Boulder limit productivity.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles Loss of riparian vegetation is prevalent throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles Lack of large woody debris exists throughout the subbasin as well as high embeddedness in spawning habitat. There has been a loss of quality pools and large woody debris in Little Boulder Creek and the gorge in Goat Creek.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass nine mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles Avian and pinniped predation are concerns. Walleye and smallmouth bass prey on salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; Juveniles Increased sediment load and high percentage of fines exists in the depositional areas. Water temperatures limit spring Chinook spawning and incubation from river mile 0-4 in the Lower Twisp. Increased sediment load below Buttermilk Creek (Lower Twisp) is problematic.
WESTSLOPE CUTTHROAT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Two passage barriers (culverts) exist in the lower 3.5 miles of the Black Canyon/Squaw Creek. Methow Valley Irrigation District canal diversion and culverts are impediments in the Lower Twisp. Flow diversions are present in the Lower Chewuch River as well as culverts in Cub and Little Boulder creeks (Lower Chewuch River). A road confinement velocity barrier exists in Eightmile Creek.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris exists throughout the subbasin as well as high embeddedness in spawning habitat. There has been a loss of quality pools and large woody debris in Little Boulder Creek and the gorge in Goat Creek.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Loss of riparian vegetation is prevalent throughout the subbasin.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Increased sediment load and high percentage of fines exists in the depositional areas. Increased sediment load below Buttermilk Creek (Lower Twisp) is problematic.
Water Quantity Increased Water Quantity; Decreased Water Quantity -- Forest Management Water: Storage or Withdrawal Juveniles, adults Increased peak flows and increased flashy flows exist due to fires in the headwaters. Low flows persist due to natural losing at river mile 0-4.3 on Wolf Creek.

Okanogan Subbasin 402, 405

Bull Trout
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Food Competition -- Species Management Species Introduction Juveniles, adults Introduction of brook trout threatens bull trout through competition and hybridization
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Irrigation diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of habitat diversity, lack of prespawn holding areas, and large woody debris.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices Riparian Degradation Juveniles, adults Cattle grazing threatens riparian function and groundwater inputs
Instantaneous Mortality Predation -- Species Management Species Introduction Juveniles Non-native predator fishes are limiting survival of juvenile salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Channel modifications have led to increased lateral erosion that creates large areas of sand and silt substrate. High levels of sedimentation create problems throughout the subbasin.
Water Quality Temperature; Oxygen; Turbidity -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All High temperature, low dissolved oxygen, and sedimentation create problems throughout the subbasin.
Water Quantity Decreased Water Quantity -- Dam or Hydropower Facility Management Water: Storage or Withdrawal Juveniles, adults Lack of flow functions as a barrier in streams throughout the subbasin limiting immigration and emigration.
RAINBOW TROUT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Irrigation diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of habitat diversity, lack of prespawn holding areas, and large woody debris.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices Riparian Degradation Juveniles, adults Cattle grazing threatens riparian function and groundwater inputs
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Channel modifications have led to increased lateral erosion that creates large areas of sand and silt substrate. High levels of sedimentation create problems throughout the subbasin.
Water Quality Temperature; Oxygen; Turbidity -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All High temperature, low dissolved oxygen, and sedimentation create problems throughout the subbasin.
Water Quantity Decreased Water Quantity -- Dam or Hydropower Facility Management Water: Storage or Withdrawal Juveniles, adults Lack of flow functions as a barrier in streams throughout the subbasin limiting immigration and emigration.
SOCKEYE
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of habitat diversity, lack of prespawn holding areas, and large woody debris.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices Riparian Degradation Juveniles, adults Cattle grazing threatens riparian function and groundwater inputs
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass nine mainstem dams during migration.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Channel modifications have led to increased lateral erosion that creates large areas of sand and silt substrate. High levels of sedimentation create problems throughout the subbasin.
Water Quality Temperature; Oxygen; Turbidity -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All High temperature, low dissolved oxygen, and sedimentation create problems throughout the subbasin.
SPRING CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Irrigation diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of habitat diversity, lack of prespawn holding areas, and large woody debris.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Cattle grazing threatens riparian function and groundwater inputs
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Spring Chinook are subject to fresh water harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass nine mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles An increase in populations of indigenous predator fish species, and the immigration of diving birds are limiting survival of juvenile salmonids. Non-native predator fishes are limiting survival of juvenile salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Channel modifications have led to increased lateral erosion that creates large areas of sand and silt substrate. High levels of sedimentation create problems throughout the subbasin.
Water Quality Temperature; Oxygen; Turbidity -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All High temperature, low dissolved oxygen, and sedimentation create problems throughout the subbasin.
SUMMER CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Irrigation diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of habitat diversity, lack of prespawn holding areas, and large woody debris.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Cattle grazing threatens riparian function and groundwater inputs
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Summer Chinook are subject to fresh water harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass nine mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles An increase in populations of indigenous predator fish species, and the immigration of diving birds are limiting survival of juvenile salmonids. Non-native predator fishes are limiting survival of juvenile salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Channel modifications have led to increased lateral erosion that creates large areas of sand and silt substrate. High levels of sedimentation create problems throughout the subbasin.
Water Quality Temperature; Oxygen; Turbidity -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All High temperature, low dissolved oxygen, and sedimentation create problems throughout the subbasin.
SUMMER STEELHEAD
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Irrigation diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of habitat diversity, lack of prespawn holding areas, and large woody debris.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Riparian Degradation Juveniles, adults Cattle grazing threatens riparian function and groundwater inputs
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass nine mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles An increase in populations of indigenous predator fish species, and the immigration of diving birds are limiting survival of juvenile salmonids. Non-native predator fishes are limiting survival of juvenile salmonids.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces; Sediment: Bank Destabilization; All Channel modifications have led to increased lateral erosion that creates large areas of sand and silt substrate. High levels of sedimentation create problems throughout the subbasin.
Water Quality Temperature; Oxygen; Turbidity -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All High temperature, low dissolved oxygen, and sedimentation create problems throughout the subbasin.

Wenatchee Subbasin 406, 407

BULL TROUT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Food Competition -- Species Management Species Introduction Juveniles Competition with brook trout limits bull trout productivity in the upper watersheds.
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris is a problem throughout the subbasin due to land development, roads, and railroad. Lack of high quality cover, refugia, and diverse habitat types along the stream margin also limit productivity. In-channel conditions have been altered by channel straightening, channelization, and simplification.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management Riparian Degradation Juveniles, adults Riparian habitat, channel sinuosity, floodplain function, and off-channel habitat have been lost or degraded. Canopy loss exits on harvested upland habitat.
Instantaneous Mortality Predation -- Species Management Species Introduction Juveniles Predation by brook trout limits bull trout productivity in the upper watersheds.
Water Quality Temperature; Oxygen; pH -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All The Lower Wenatchee River is on the WDOE 303d list for temperature, pH, and dissolved oxygen. Chiwaukum and Peshastin creeks are also on the 303d list for temperature exceedences. Mission Creek is listed for low dissolved oxygen, high fecal coliform, and pesticides. Chumstick Creek is included on the list for dissolved oxygen, fecal coliform, and pH exceedences. The Little Wenatchee River is listed for temperature exceedence.
Water Quantity Decreased Water Quantity -- Dam or Hydropower Facility Management Water: Storage or Withdrawal Juveniles, adults Low flows are exacerbated by surface water diversions and ground water withdrawals. The Mission, Peshastin, Chumstick, Icicle creeks and Lower Wenatchee River, are 303d listed for low in-stream flows. Low flows and associated high in-stream temperatures prevent or impeded access to spawning grounds and reduce rearing habitat.
COHO
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris is a problem throughout the subbasin due to land development, roads, and railroad. Lack of high quality cover, refugia, and diverse habitat types along the stream margin also limit productivity. In-channel conditions have been altered by channel straightening, channelization, and simplification.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management Riparian Degradation Juveniles, adults Riparian habitat, channel sinuosity, floodplain function, and off-channel habitat have been lost or degraded. Canopy loss exits on harvested upland habitat.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Coho are subject to ocean and fresh water harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass seven mainstem dams during migration.
Water Quality Temperature; Oxygen; pH -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All The Lower Wenatchee River is on the WDOE 303d list for temperature, pH, and dissolved oxygen. Chiwaukum and Peshastin creeks are also on the 303d list for temperature exceedences. Mission Creek is listed for low dissolved oxygen, high fecal coliform, and pesticides. Chumstick Creek is included on the list for dissolved oxygen, fecal coliform, and pH exceedences. The Little Wenatchee River is listed for temperature exceedence.
PACIFIC LAMPREY
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles; adults Juveniles and adults must pass seven mainstem dams during migration.
Water Quality Temperature; Oxygen; pH -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All The Lower Wenatchee River is on the WDOE 303d list for temperature, pH, and dissolved oxygen. Chiwaukum and Peshastin creeks are also on the 303d list for temperature exceedences. Mission Creek is listed for low dissolved oxygen, high fecal coliform, and pesticides. Chumstick Creek is included on the list for dissolved oxygen, fecal coliform, and pH exceedences. The Little Wenatchee River is listed for temperature exceedence.
Water Quantity Decreased Water Quantity -- Dam or Hydropower Facility Management Water: Storage or Withdrawal Juveniles, adults Low flows are exacerbated by surface water diversions and ground water withdrawals. The Mission, Peshastin, Chumstick, Icicle creeks and Lower Wenatchee River, are 303d listed for low in-stream flows. Low flows and associated high in-stream temperatures prevent or impeded access to spawning grounds and reduce rearing habitat.
SOCKEYE
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris is a problem throughout the subbasin due to land development, roads, and railroad. Lack of high quality cover, refugia, and diverse habitat types along the stream margin also limit productivity. In-channel conditions have been altered by channel straightening, channelization, and simplification.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management Riparian Degradation Juveniles, adults Riparian habitat, channel sinuosity, floodplain function, and off-channel habitat have been lost or degraded. Canopy loss exits on harvested upland habitat.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass seven mainstem dams during migration.
Water Quality Temperature; Oxygen; pH -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All The Lower Wenatchee River is on the WDOE 303d list for temperature, pH, and dissolved oxygen. Chiwaukum and Peshastin creeks are also on the 303d list for temperature exceedences. Mission Creek is listed for low dissolved oxygen, high fecal coliform, and pesticides. Chumstick Creek is included on the list for dissolved oxygen, fecal coliform, and pH exceedences. The Little Wenatchee River is listed for temperature exceedence.
SPRING CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris is a problem throughout the subbasin due to land development, roads, and railroad. Lack of high quality cover, refugia, and diverse habitat types along the stream margin also limit productivity. In-channel conditions have been altered by channel straightening, channelization, and simplification.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management Riparian Degradation Juveniles, adults Riparian habitat, channel sinuosity, floodplain function, and off-channel habitat have been lost or degraded. Canopy loss exits on harvested upland habitat.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Spring Chinook are subject to fresh water harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass seven mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles An increase in populations of indigenous predator fish species, and the immigration of diving birds are limiting survival of juvenile salmonids. Non-native predator fishes are limiting survival of juvenile salmonids.
Water Quality Temperature; Oxygen; pH -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All The Lower Wenatchee River is on the WDOE 303d list for temperature, pH, and dissolved oxygen. Chiwaukum and Peshastin creeks are also on the 303d list for temperature exceedences. Mission Creek is listed for low dissolved oxygen, high fecal coliform, and pesticides. Chumstick Creek is included on the list for dissolved oxygen, fecal coliform, and pH exceedences. The Little Wenatchee River is listed for temperature exceedence.
SUMMER CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris is a problem throughout the subbasin due to land development, roads, and railroad. Lack of high quality cover, refugia, and diverse habitat types along the stream margin also limit productivity. In-channel conditions have been altered by channel straightening, channelization, and simplification.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management Riparian Degradation Juveniles, adults Riparian habitat, channel sinuosity, floodplain function, and off-channel habitat have been lost or degraded. Canopy loss exits on harvested upland habitat.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Summer Chinook are subject to fresh water harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass seven mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles An increase in populations of indigenous predator fish species, and the immigration of diving birds are limiting survival of juvenile salmonids. Non-native predator fishes are limiting survival of juvenile salmonids.
Water Quality Temperature; Oxygen; pH -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All The Lower Wenatchee River is on the WDOE 303d list for temperature, pH, and dissolved oxygen. Chiwaukum and Peshastin creeks are also on the 303d list for temperature exceedences. Mission Creek is listed for low dissolved oxygen, high fecal coliform, and pesticides. Chumstick Creek is included on the list for dissolved oxygen, fecal coliform, and pH exceedences. The Little Wenatchee River is listed for temperature exceedence.
SUMMER STEELHEAD
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Access and Availability; Morphological Changes Estuary Agricultural Practices; Urbanization Diking; Filling; Riparian Degradation; Wetland Loss Smolts Historical complex habitats have been modified through channelization, diking, development and other practices.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris is a problem throughout the subbasin due to land development, roads, and railroad. Lack of high quality cover, refugia, and diverse habitat types along the stream margin also limit productivity. In-channel conditions have been altered by channel straightening, channelization, and simplification.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management Riparian Degradation Juveniles, adults Riparian habitat, channel sinuosity, floodplain function, and off-channel habitat have been lost or degraded. Canopy loss exits on harvested upland habitat.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass seven mainstem dams during migration.
Instantaneous Mortality Competition; Pathogens -- Artificial Propagation Hatchery Fish Production; Disease Amplification and Transfer Juveniles Competition, genetic introgression, and disease transmission from hatchery introductions may reduce productivity.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian; Predators: Marine Mammal Juveniles An increase in populations of indigenous predator fish species, and the immigration of diving birds are limiting survival of juvenile salmonids. Non-native predator fishes are limiting survival of juvenile salmonids.
Water Quality Temperature; Oxygen; pH -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All The Lower Wenatchee River is on the WDOE 303d list for temperature, pH, and dissolved oxygen. Chiwaukum and Peshastin creeks are also on the 303d list for temperature exceedences. Mission Creek is listed for low dissolved oxygen, high fecal coliform, and pesticides. Chumstick Creek is included on the list for dissolved oxygen, fecal coliform, and pH exceedences. The Little Wenatchee River is listed for temperature exceedence.
WESTSLOPE CUTTHROAT
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage (s) Description
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Diversion dams and culverts create fish passage barriers throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Urbanization Riparian Degradation; Bank Destabilization Juveniles, adults Lack of large woody debris is a problem throughout the subbasin due to land development, roads, and railroad. Lack of high quality cover, refugia, and diverse habitat types along the stream margin also limit productivity. In-channel conditions have been altered by channel straightening, channelization, and simplification.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management Riparian Degradation Juveniles, adults Riparian habitat, channel sinuosity, floodplain function, and off-channel habitat have been lost or degraded. Canopy loss exits on harvested upland habitat.
Water Quality Temperature; Oxygen; pH -- Agricultural Practices; Forest Management; Urbanization; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Temperature and Gas Alteration All The Lower Wenatchee River is on the WDOE 303d list for temperature, pH, and dissolved oxygen. Chiwaukum and Peshastin creeks are also on the 303d list for temperature exceedences. Mission Creek is listed for low dissolved oxygen, high fecal coliform, and pesticides. Chumstick Creek is included on the list for dissolved oxygen, fecal coliform, and pH exceedences. The Little Wenatchee River is listed for temperature exceedence.
Water Quantity Decreased Water Quantity -- Dam or Hydropower Facility Management Water: Storage or Withdrawal Juveniles, adults Low flows are exacerbated by surface water diversions and ground water withdrawals. The Mission, Peshastin, Chumstick, Icicle creeks and Lower Wenatchee River, are 303d listed for low in-stream flows. Low flows and associated high in-stream temperatures prevent or impeded access to spawning grounds and reduce rearing habitat.