Province Summary


Yakima Subbasin Summary

The Yakima River Subbasin encompasses an area of just over 6,100 square miles in south central Washington. It is bordered on the west by the crest of the Cascade Mountains, on the north by the Wenatchee Mountains, on the east by the breaks of the Columbia River, and on the south by the Simcoe Mountains and the Horse Heaven Hills. The major geologic actions affecting the formation of the Yakima Subbasin have been volcanoes and lava flows, glaciation, and uplifting.

The subbasin contains a variety of aquatic habitats; the large mainstem of the Yakima River; medium-size rivers such as the upper Yakima, Cle Elum, and Naches; and many smaller tributaries, such as the Little Naches River, Satus, Ahtanum, and Taneum creeks, and the headwaters above the subbasin’s reservoirs.

Private ownership totals 32 percent or over 1.2 million acres of the 4 million acres in the Yakima Subbasin. The single largest landowner is the U.S government with 1.5 million acres or 38 percent of the land area. Most of the federal land is within the Wenatchee National Forest. Other large federal land holding include the U.S. Army Yakima Training Center, the Hanford Nuclear Reservation, and Bureau of Land Management lands. Other public ownership (state, county, and local governments) total over 400,000 acres. The Yakama Nation Reservation covers 1,573 square miles (1,371,918 acres) in southern Yakima County and a smaller part of Klickitat County. The Yakama Nation and its members have over 880,000 acres held in trust; only a small portion is deeded land.

Nearly 40 percent of the basin is forested, another 40 percent is rangeland, 15 percent cropland, and the remaining acreage includes other land uses and water bodies. The predominant types of land use in the Yakima Subbasin include grazing (2,900 square miles), timber harvesting (2,200 square miles), irrigated agriculture (1,000 square miles), and urbanization (50 square miles).

The estimated population of Yakima County has increased from about 223,000 in 2000 to 239,000 in 2009. About 85,000 people live in the city of Yakima, up from 72,000 in 2000. The Yakima Valley’s growth has been fueled primarily by agriculture. In addition to producing many fruit and vegetable crops, the Yakima Valley is now home to over 50 wineries, covering more than 11,000 acres.

Extensive efforts to restore and recover fish populations in the Yakima Subbasin have been underway for some time. Efforts to recover listed steelhead are coordinated in part by the Yakima Basin Fish and Wildlife Recovery Board. Efforts to enhance all stocks of anadromous fish in the subbasin are led primarily by the Yakama Nation and the Washington Department of fish and Wildlife through the Yakima/Klickitat Fisheries Project.

Focal Species Narratives for the Yakima Subbasin
Fall Chinook

Little is known about the historical abundance and distribution of fall Chinook salmon in the Yakima Subbasin, although the primary production area is believed to be generally similar to that of today; the lower 100 miles of the Yakima mainstem, from the current site of the Sunnyside Dam to the Columbia River confluence. Abundance has been severely reduced from the historic levels of 38,000 to 100,000 adults.

There are two genetically distinct stocks (populations) of fall Chinook recognized in the Yakima Subbasin. The mainstem stock is found throughout the lower mainstem, and the Marion Drain stock is endemic to the Marion Drain. The Marion Drain is a unique, artificial feature of the subbasin, consisting of a 19-mile-long drainage ditch for the Wapato Irrigation Project (WIP). The original ditch was dug early in the 20th century to drain wetlands and was enlarged over the years to serve as a major delivery canal for WIP. It discharges into the Yakima River 2.2 miles upstream of the mouth of Toppenish Creek.

In 1996 the Yakama Nation constructed the Lower Yakima Supplementation and Research Facility at Prosser Dam. Adult broodstock are collected at Prosser Dam. Yakima River Mainstem fall Chinook are not a distinct population from the Hanford Reach fall Chinook; however, genetic introgression or damage to the Hanford Reach fall Chinook or Lower Yakima fall Chinook from Prosser hatchery releases is likely low due to the small proportion of this combined stock that is currently of hatchery origin.

Spring Chinook Salmon

Spring Chinook salmon were once widely distributed in the Yakima Subbasin; however, historic abundance is poorly known. Capacity estimates for the Yakima Subbasin range from 200,000 to 500,000 spawning adults. Although considerable uncertainty exists for estimates of historic abundance, it is clear that populations decreased markedly throughout the upper Columbia Basin as a whole with the construction of mainstem dams.

The current distribution of spring Chinook salmon in the Yakima Subbasin has been reduced, but is still relatively similar to historic distribution. Notable exceptions include streams rendered inaccessible or unusable by un-laddered dams or by excessive irrigation diversions or releases. Spring Chinook abundance is commonly monitored by counting the number of fish passing through dams.

Three genetically distinct stocks (populations) of spring Chinook have been identified in the Yakima Subbasin: the upper Yakima, the Naches, and the American River stocks. The Upper Yakima stock is a native stock with composite production, and the Naches and American River stocks are native stocks with wild production. The Upper Yakima Stock includes the Yakima River, the Teanaway River, and Swauk Creek. The Naches River stock includes the Naches River, the Tieton River, and Rattlesnake Creek. The American River stock resides exclusively in the American River. Each stock has pronounced differences in terms of ocean age, mean fecundity, the spawning timing, and perhaps sex ratio. Conservation of the genetic diversity and the unique life history traits of each individual stock is an important objective of the Yakima Subbasin plan.

The Yakima/Klickitat Fisheries Project (YKFP) began artificial production of spring Chinook (upper Yakima) in 1997 with the completion of the Cle Elum Supplementation and Research Facility (CESRF). This facility was designed to conduct research on hatchery supplementation. The Northwest Power Planning Council stated, “the purpose of the Yakima/Klickitat Production Project is to test the assumption that new artificial production can be used to increase harvest and natural production while maintaining genetic resources�.

Sockeye Salmon

Sockeye salmon populations reportedly existed in two small lakes at the head of the Yakima River on the present site of Lake Keechelus, as well as in Cle Elum Lake, in Kachess Lake, and in Bumping Lake. Estimates of the historical total run size of Yakima River sockeye salmon range from 100,000 to 200,000 adults. Sockeye were extirpated following the completion of impassible dams below all natural rearing lakes by the early 1920’s.

Self-sustaining populations of kokanee salmon exist in Rimrock, Kachess, Cle Elum, Bumping, and Keechelus lakes. The Rimrock Lake population has a hatchery origin. The origin of other populations can be traced to historical populations that were present in the high elevation lakes before they were converted into reservoirs, with periodic introductions. There have been widespread introductions of hatchery kokanee since the 1980’s, so it cannot be positively affirmed to what extent the natural origin stocks have been diluted.

Sockeye are now being reintroduced into the Yakima Subbasin by collecting adults at Priest Rapids Dam on the Columbia River, transporting them, and releasing them into Cle Elum Lake. Plans call for up to 1,000 sockeye adults to be collected each year depending on availability; however, after transporting 1,000 adults in 2009, a strong run in 2010 allowed 2,500 to be transported.. Two thousand were put in Cle Elum Lake and 500 were released into Cooper Lake. Downstream-migrating juveniles will use the spillways at Cle Elum Dam, and returning adults will depend on an adult trap and haul facility. Longer-term solutions to passage obstacles are being discussed.

Summer Steelhead

Steelhead are the most widespread anadromous fish in the Yakima Subbasin. They range from intermittent streams in semi-arid watersheds to headwaters high in the Cascades. The historical annual return of adult steelhead to the Yakima Subbasin has been estimated to range from 20,800 to 100,000. The Yakima Steelhead Recovery Plan considers estimates from 25,000 to 75,000 to be reasonable.

Current returns, as estimated by counts at Prosser Dam, are far below historic returns. Yakima Subbasin steelhead are listed as threatened under the Endangered Species Act, and are the upstream-most component of the Middle Columbia River Distinct Population Segment. Populations within the Yakima subbasin include Satus Creek, Toppenish Creek, Naches River, and Upper Yakima. The Satus population is further divided into two parts: the Satus Creek block, which spawns within the Satus Creek watershed, and the mainstem block, which spawns in the lower mainstem and its tributaries below Satus Creek. While the Satus Creek block represents an area with known and wide spread spawning, the current and historic status of the mainstem block is uncertain.

Hatchery releases of steelhead into the Yakima Subbasin ceased after 1993.The run is dominated by wild fish, with the proportion of returning spawners that are of natural origin averaging only 3% since 1999.

Pacific Lamprey

Little is known about the historic distribution and abundance of Pacific lamprey in the Yakima Subbbasin. These fish were numerous, and were especially important to Native Americans for medicinal and ceremonial purposes and were considered a delicacy by many Columbia Basin tribes.

Population levels of Pacific lamprey have been dramatically reduced from historic levels, with only about 14 fish on average observed annually at Prosser Dam. Known distribution is limited to the mainstem Yakima and Naches Rivers. Pacific lamprey is a Washington State species of concern and is under consideration for ESA listing by the U.S. Fish and Wildlife Service.

Work has recently begun to restore natural production of Pacific lamprey in the Yakima Subbasin. Work will initially focus on collecting and reporting information to evaluate status, relative abundance and distribution. Known and potential limiting factors will then be identified, and finally, development and implementation of restoration actions will be undertaken. Restoration actions may include translocation and supplementation.

Bull Trout

Historic abundance of bull trout in the Yakima subbasin is not well understood. It is likely fluvial, adfluvial, and resident life history forms were found historically throughout the basin. Estimates of current abundance range from 250 to 1,000 migratory adults in the Yakima River Core Area.

Historically, bull trout existed throughout the Yakima River Basin; however, through time populations became isolated. Currently, 13 bull trout local populations exist in the Yakima subbasin. All are native fish sustained by wild production. Most are considered adfluvial, with the remainder being fluvial or resident.

The U.S. Fish and Wildlife Service considers isolation by dams to be a major threat to bull trout in the Yakima River Core Area and agricultural practices and associated water withdrawal as a threat to each subpopulation. Additional threats for bull trout in the Yakima Subbasin includeforestry practices, grazing, roads, mining, harvest, non-native species, and residential development.

Coho Salmon

Although not selected as a focal species during the subbasin planning process, coho salmon were historically one of the most numerous anadromous salmonids returning to the subbasin, with average historical run sizes estimated at 44,000 to 150,000 adults. There could have been as many as 17 independent populations of coho based on historic distribution maps. Coho were extirpated from the Yakima Subbasin by the 1970s due to a combination of effects of the hydrosystem, habitat loss, and over harvest in the mainstem Columbia River. Changes that have been made in the hydrosystem, harvest management and habitat restoration activities (e.g. structural, flow, barriers) in the subbasin have reversed the factors for decline of coho, and could increase the productivity and abundance of reintroduced coho populations.

The Yakima/Klickitat Fisheries Project is currently working to re-establish coho salmon in the Yakima Subbasin. Efforts have relied largely upon releases of hatchery coho derived from Lower Columbia river stocks. Since 1995, the primary purposes of these releases has been to test the feasibility of re-establishing natural production.

In 2009, 8,518 adult coho were counted at Prosser Dam, which was about 37% of all adult anadromous salmonids counted. Counts at Roza dam totaled 1,164, or about 18% of all adult anadromous salmonids

Status and Trends of Focal Species in Yakima Subbasin
 
Species ESU MPG Population Biological Objective (s) Biological Status Federal Status Data / Charts
Fall Chinook   Yakima  Marion Drain and Yakima  Subbasin Plan Objective :
None
Recovery Plan Criteria :
None
 
Adult Counts (Prosser Dam) (mixed)
2016: 4,941 adults 99
Not Listed Status & Trends
Spring Chinook   Yakima  American, Naches, Upper Yakima  Subbasin Plan Objective :
None
Recovery Plan Criteria :
None
 
Redd Counts
2017: 836 redds 102
Not Listed Status & Trends
Pacific Lamprey       Subbasin Plan Objective :
None
 
Adult Counts
2017: 561 adults463
Species of Concern Status & Trends
Sockeye       Subbasin Plan Objective :
None
Cleelum Lake Potential - 30-50,000 adults435
Bumping Lake Potential - 10-17,000 adults323
 
Adult Count (Prosser Dam)
2017: 372 adults (wild)275
Not Listed Status & Trends
Summer Steelhead Middle Columbia  Yakima  Naches, Satus, Toppenish and Upper Yakima  Recovery Plan Criteria :
(Delisting Threshold)302
Naches River - 1,500 adults
Satus Creek - 500 natural adults (plus additional 500 in lower mainstem or in another population)
Toppenish Creek - 250 natural adults
Upper Yakima - 500 adults302
 
Adult Counts (Prosser Dam) (mixed)
2017: 2,566 adults 100
Redd Counts
2016: 197 redds
Threatened Status & Trends
Bull Trout Yakima (Within Middle Columbia River Recovery Unit)      Draft Recovery Plan Criteria :
2,550 - 3050 adults287
Subbasin Plan Objective :
None
 
Redd Counts
2011: 760 redds
South Fork Ahtanum - 4 redds 87
Middle Fork Ahtanum - 11 redds 87
Gold Creek - 7 redds 87
Bumping River - 0 redds 87
Crow Creek - 7 redds 87
North Fork Tieton River - 11 redds 87
Kachess River - 33 redds 87
Box Canyon Creek - 31 redds 87
Indian Creek - 147 redds 87
Deep Creek - 19287
American River/Union Creek - 40 redds 87
Ahtanum North Fork/Shellneck Creek - 1 redd87
Teanaway North Fork River/De Roux - 0 redds 87
Rattlesnake Creek/Little Wildcat/Shell Creek - 42 redds 87
Tieton South Fork/Bear Creek - 234 redds 87
Threatened Status & Trends
    
View abundance data for Yakima Subbasin
 
Hatcheries located in Yakima Subbasin
**Hatchery data will be updated in 2016**

Hatchery / Acclimation Pond Hatchery Info Releases / Returns Program Reviews(APRE / HSRG / HGMP / USFWS) Map
Clark Flat View View View  
Cle Elum View   View View
Easton View View View  
Holmes Pond View View    
Jack Creek View View    
Lost Creek Pond View View    
Marion Drain View View View  
Naches Hatchery View View   View
Prosser Hatchery View View View View
Stile Pond View View    
Yakima Hatchery View     View
 
Hatchery Releases and Returns to Yakima Subbasin363, 359, 360
**Hatchery data will be updated in 2016**

Some releases into subbasins may be from hatcheries located in other provinces and subbasins. Hatchery releases of anadromous fish, within the geographic range of an ESU/DPS, are listed accordingly.
 
Hatchery / Acclimation Pond Species ESU/DPS Released in 2009 Returns to Collection Facility in 2009 Data as of
Chelan PUD Hatchery Westslope Cutthroat 195,068 8 / 30 / 2010
Chelan State Fish Hatchery Kokanee 393,507 8 / 30 / 2010
Clark Flat Spring Chinook 265,907 8 / 30 / 2010
Columbia Basin Hatchery Rainbow Trout 8,613 8 / 30 / 2010
Easton Coho 112,842 8 / 30 / 2010
Spring Chinook 254,540 8 / 30 / 2010
Goldendale Trout Hatchery Rainbow Trout 12,647 8 / 30 / 2010
Holmes Pond Coho 145,714 8 / 30 / 2010
Jack Creek Spring Chinook 250,818 8 / 30 / 2010
Lost Creek Pond Coho 164,330 8 / 30 / 2010
Marion Drain Fall Chinook 24,245 8 / 30 / 2010
Mossyrock Trout Hatchery Rainbow Trout 10,800 8 / 30 / 2010
Naches Hatchery Golden Trout 2,945 8 / 30 / 2010
Kokanee 237,360 8 / 30 / 2010
Rainbow Trout 212,114 8 / 30 / 2010
Westslope Cutthroat 9,458 8 / 30 / 2010
Prosser Hatchery Coho 109,549 8 / 30 / 2010
Fall Chinook 1,954,365 8 / 30 / 2010
Stile Pond Coho 275,447 8 / 30 / 2010
Summer Chinook 180,911 8 / 30 / 2010
Tokul Creek Hatchery Golden Trout 2,548 8 / 30 / 2010
Rainbow Trout 2,240 8 / 30 / 2010
Westslope Cutthroat 1,120 8 / 30 / 2010
Trout Lodge Commercial Rainbow Trout 2,897 8 / 30 / 2010
Recovery Status for ESA-Listed Salmon and Steelhead in the Yakima Subbasin376

Updated : 1/5/2011

Species Population Abundance Threshold Mean Abundance Major Spawning Area Growth Rate Recruits / Spawners Current Viability
Steelhead Satus 500
500 additional
in lower mainstem
620 2 of 2 Unknown 1.73 Moderate
  Toppenish 250 542 2 of 2 Unknown 1.6 Moderate
  Naches 1,500 770 7 of 8 Unknown 1.12 Low
  Upper Yakima 500 134 7 of 14 Unknown 1 Low
Limiting Factors in the Yakima Subbasin 393, 397, 376

BULL 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 Migration Impediments Juveniles, adults Partial or total flow/temperature blockages to fish migrations due to diversions exist throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management Riparian Degradation; Bank Destabilization; Water: Runoff Coefficient Alteration. Juveniles, adults Riparian communities (particularly black cottonwood) in the mainstem Yakima and Naches rivers are degraded due to changes in the hydrograph. Channel incision has disconnected Toppenish Creek from the floodplain below Simcoe Creek. Riparian vegetation in Toppenish Creek between Unit II Pump Canal and Star Route 22 has been modified by grazing and irrigated agriculture.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Riparian Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Riparian Degradation Juveniles, adults Grazing impacts affect bull trout during spawning periods. Problems associated with channel incision, bank stability, and riparian vegetation removal exist throughout the subbasin.
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Sediment: Bank Destabilization; Sediment: Upland Disturbance All Elevated sediment loads exist throughout the subbasin due to high road densities, increases in peak flows, bank erosion, and floodplain loss.
Toxic Contaminants Water -- Pollution or Contamination Pollution: Biological Wastes, Fertilizer, & Pharmaceuticals All High toxic pollutant levels exist in sediments throughout the subbasin.
Water Quantity Altered Flow Timing -- Dam or Hydropower Facility Management Water: Storage or Withdrawal Juveniles, adults The annual hydrograph has been modified. Upstream of Union Gap, the hygrograph has been “flattened” affecting riparian and ecosystem function, productivity, and stability. Annual flow is reduced from Parker to Toppenish Creek/Marion Dam. Sustained high flows in the upper Yakima downstream to Union Gap limit habitat diversity. Low flows are problematic throughout the subbasin.
FALL CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage(s) Description
Food Competition -- Species Management Species Introduction Juveniles Altered fish communities have resulted in high levels of predation and competition.
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 Morphological Changes Freshwater-Floodplain Agricultural Practices; Forest Management; Urbanization Wetland Loss; Impervious Surfaces (Road Density); Riparian Degradation Juveniles Problems associated with channel incision, bank stability, and riparian vegetation removal exist throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Water: Storage or Withdrawal; Riparian Degradation Fry Summer/early-fall habitat availability is low or eliminated by low flow and high temperature in the lower Yakima River and Wapato Reach. Lack of habitat diversity and large woody debris is problematic throughout the subbasin. Excessive growth of in-channel aquatic vegetation in the lower/middle Yakima is problematic.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes; altered Flow Timing Freshwater-Riparian Agricultural Practices; Dam or Hydropower Facility Management Riparian Degradation; Water: Hydrologic Cycle Alteration Juveniles Riparian communities (particularly black cottonwood) in the mainstem Yakima and Naches rivers are degraded due to changes in the hydrograph. Riparian vegetation in Toppenish Creek between Unit II Pump Canal and Star Route 22 has been modified by grazing and irrigated agriculture. Problems associated with channel incision, bank stability, and riparian vegetation removal exist throughout the subbasin.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Fall Chinook are subject to both ocean and freshwater harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass four dams during migration.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian Juveniles Avian and fish predation problems exist throughout the subbasin
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Sediment: Bank Destabilization; Sediment: Upland Disturbance Juveniles Elevated sediment loads exist throughout the subbasin due to high road densities, increases in peak flows, bank erosion, and floodplain loss.
Toxic Contaminants Water -- Pollution or Contamination Pollution: Biological Wastes, Fertilizer, & Pharmaceuticals All High toxic pollutant levels exist in sediments throughout the subbasin.
Water Quality Temperature -- Agricultural Practices; Forest Management; Urbanization Water: Temperature and Gas Alteration Juveniles Elevated summer temperatures exist in lower reaches of tributaries and headwaters due to development, forest management, and grazing practices. Temperatures in the lower Yakima and Wapato Reach have increased to a point that returning fall-run adults must delay river entry and juveniles must migrate from the river earlier. The mainstem Middle Fork, North Fork, West Fork Teanaway River, and Stafford Creek are 303(d) listed for water temperature.
Water Quantity Altered Flow Timing; Decreased Water Quantity -- Agricultural Practices; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Hydrologic Cycle Alteration; Water: Runoff Coefficient Alteration. Juveniles The annual hydrograph has been modified. Upstream of Union Gap, the hygrograph has been “flattened” affecting riparian and ecosystem function, productivity, and stability. Annual flow is reduced from Parker to Toppenish Creek/Marion Dam. Sustained high flows in the upper Yakima downstream to Union Gap and sustained low flows to lower Naches and from Union Gap downstream limit habitat diversity. Low flows are problematic throughout the subbasin.
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 Migration Impediments Juveniles, adults Partial or total flow/temperature blockages to fish migrations due to diversions exist 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 Juveniles and adults must pass four dams during migration.
Toxic Contaminants Water -- Pollution or Contamination Pollution: Biological Wastes, Fertilizer, & Pharmaceuticals All High toxic pollutant levels exist in sediments throughout the subbasin.
Water Quality Temperature -- Agricultural Practices; Forest Management; Urbanization Water: Temperature and Gas Alteration Juveniles Elevated summer temperatures exist in lower reaches of tributaries and headwaters due to development, forest management, and grazing practices. Temperatures in the lower Yakima and Wapato Reach have increased to a point that returning fall-run adults must delay river entry and juveniles must migrate from the river earlier. The mainstem Middle Fork, North Fork, West Fork Teanaway River, and Stafford Creek are 303(d) listed for water temperature.
Water Quantity Altered Flow Timing; Decreased Water Quantity -- Agricultural Practices; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Hydrologic Cycle Alteration; Water: Runoff Coefficient Alteration. Juveniles The annual hydrograph has been modified. Upstream of Union Gap, the hygrograph has been “flattened” affecting riparian and ecosystem function, productivity, and stability. Annual flow is reduced from Parker to Toppenish Creek/Marion Dam. Sustained high flows in the upper Yakima downstream to Union Gap and sustained low flows to lower Naches and from Union Gap downstream limit habitat diversity. Low flows are problematic throughout the subbasin.
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; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Obstructions have reduced the area available to sockeye. Kachess, Keechelus, and Cle Elum dams prevent access to high elevation areas for sockeye.
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 -- Fishery Management Harvest Adults Sockeye are subject to freshwater harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass four dams during migration.
SPRING CHINOOK
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage(s) Description
Food Competition -- Species Management Species Introduction Juveniles Altered fish communities have resulted in high levels of predation and competition.
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Partial or total flow/temperature blockages to fish migrations due to diversions exist throughout the subbasin. Wenas Dam prevents access to the upper Wenas Creek and dewaters lower Wenas Creek. Migratory fish cannot access Umtanum Creek upstream of river mile 4.8 due to a gabion structure. Kachess, Keechelus, and Cle Elum dams prevent access to high elevation areas for spring Chinook.
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 Morphological Changes Freshwater-Floodplain Agricultural Practices; Urbanization Wetland Loss; Impervious Surfaces (Road Density); Riparian Degradation Juveniles Channel incision has disconnected Toppenish Creek from the floodplain below Simcoe Creek.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Water: Storage or Withdrawal; Riparian Degradation Juveniles Lack of habitat diversity and large woody debris is problematic throughout the subbasin.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes; altered Flow Timing Freshwater-Riparian Agricultural Practices; Dam or Hydropower Facility Management Riparian Degradation; Water: Hydrologic Cycle Alteration Juveniles Riparian communities (particularly black cottonwood) in the mainstem Yakima and Naches rivers are degraded due to changes in the hydrograph. Riparian vegetation in Toppenish Creek between Unit II Pump Canal and Star Route 22 has been modified by grazing and irrigated agriculture. Problems associated with channel incision, bank stability, and riparian vegetation removal exist throughout the subbasin.
Instantaneous Mortality Anthropogenic Mortality -- Fishery Management Harvest Adults Spring Chinook are subject to freshwater harvest.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass four dams during migration.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian Juveniles Avian and fish predation problems exist throughout the subbasin
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Sediment: Bank Destabilization; Sediment: Upland Disturbance Juveniles Elevated sediment loads exist throughout the subbasin due to high road densities, increases in peak flows, bank erosion, and floodplain loss.
Toxic Contaminants Water -- Pollution or Contamination Pollution: Biological Wastes, Fertilizer, & Pharmaceuticals All High toxic pollutant levels exist in sediments throughout the subbasin.
Water Quality Temperature -- Agricultural Practices; Forest Management; Urbanization Water: Temperature and Gas Alteration Juveniles Elevated summer temperatures exist in lower reaches of tributaries and headwaters due to development, forest management, and grazing practices. Temperatures in the lower Yakima and Wapato Reach have increased to a point that returning fall-run adults must delay river entry and juveniles must migrate from the river earlier. The mainstem Middle Fork, North Fork, West Fork Teanaway River, and Stafford Creek are 303(d) listed for water temperature.
Water Quantity Altered Flow Timing; Decreased Water Quantity -- Agricultural Practices; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Hydrologic Cycle Alteration; Water: Runoff Coefficient Alteration. Juveniles The annual hydrograph has been modified. Upstream of Union Gap, the hygrograph has been “flattened” affecting riparian and ecosystem function, productivity, and stability. Annual flow is reduced from Parker to Toppenish Creek/Marion Dam. Sustained high flows in the upper Yakima downstream to Union Gap and sustained low flows to lower Naches and from Union Gap downstream limit habitat diversity. Low flows are problematic throughout the subbasin.
SUMMER STEELHEAD
Key Limiting Factor Impairment Habitat Affected Threat Type Threat Name Life Stage(s) Description
Food Competition -- Species Management Species Introduction Juveniles Altered fish communities have resulted in high levels of predation and competition.
Habitat Quantity and Quality Access and Availability Freshwater-Instream Agricultural Practices; Dam or Hydropower Facility Management Migration Impediments Juveniles, adults Partial or total flow/temperature blockages to fish migrations due to diversions exist throughout the subbasin. Wenas Dam prevents access to the upper Wenas Creek and dewaters lower Wenas Creek. Migratory fish cannot access Umtanum Creek upstream of river mile 4.8 due to a gabion structure. Kachess, Keechelus, and Cle Elum dams prevent access to high elevation areas for steelhead.
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 Morphological Changes Freshwater-Floodplain Agricultural Practices; Urbanization Wetland Loss; Impervious Surfaces (Road Density); Riparian Degradation Juveniles Channel incision has disconnected Toppenish Creek from the floodplain below Simcoe Creek.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Water: Storage or Withdrawal; Riparian Degradation Juveniles Summer/early-fall habitat availability is low or eliminated by low flow and high temperature in the lower Yakima River and Wapato Reach. Lack of habitat diversity and large woody debris is problematic throughout the subbasin. Excessive growth of in-channel aquatic vegetation in the lower/middle Yakima is problematic.
Habitat Quantity and Quality Small-Scale Structural Complexity; Morphological Changes; altered Flow Timing Freshwater-Riparian Agricultural Practices; Dam or Hydropower Facility Management Riparian Degradation; Water: Hydrologic Cycle Alteration Juveniles Riparian communities (particularly black cottonwood) in the mainstem Yakima and Naches rivers are degraded due to changes in the hydrograph. Riparian vegetation in Toppenish Creek between Unit II Pump Canal and Star Route 22 has been modified by grazing and irrigated agriculture. Problems associated with channel incision, bank stability, and riparian vegetation removal exist throughout the subbasin.
Instantaneous Mortality Anthropogenic Mortality -- Dam or Hydropower Facility Management Migration Impediments Juveniles Juveniles and adults must pass four dams during migration.
Instantaneous Mortality Predation -- Dam or Hydropower Facility Management; Species Management Predators: Fish; Predators: Avian Juveniles Avian and fish predation problems exist throughout the subbasin
Sediment Conditions Increased Sediment Quantity Freshwater-Instream Agricultural Practices; Forest Management; Urbanization Impervious Surfaces (Road Density); Sediment: Bank Destabilization; Sediment: Upland Disturbance Juveniles Elevated sediment loads exist throughout the subbasin due to high road densities, increases in peak flows, bank erosion, and floodplain loss.
Toxic Contaminants Water -- Pollution or Contamination Pollution: Biological Wastes, Fertilizer, & Pharmaceuticals All High toxic pollutant levels exist in sediments throughout the subbasin.
Water Quality Temperature -- Agricultural Practices; Forest Management; Urbanization Water: Temperature and Gas Alteration Juveniles Elevated summer temperatures exist in lower reaches of tributaries and headwaters due to development, forest management, and grazing practices. Temperatures in the lower Yakima and Wapato Reach have increased to a point that returning fall-run adults must delay river entry and juveniles must migrate from the river earlier. The mainstem Middle Fork, North Fork, West Fork Teanaway River, and Stafford Creek are 303(d) listed for water temperature.
Water Quantity Altered Flow Timing; Decreased Water Quantity -- Agricultural Practices; Dam or Hydropower Facility Management Water: Storage or Withdrawal; Water: Hydrologic Cycle Alteration; Water: Runoff Coefficient Alteration. Juveniles The annual hydrograph has been modified. Upstream of Union Gap, the hygrograph has been “flattened” affecting riparian and ecosystem function, productivity, and stability. Annual flow is reduced from Parker to Toppenish Creek/Marion Dam. Sustained high flows in the upper Yakima downstream to Union Gap and sustained low flows to lower Naches and from Union Gap downstream limit habitat diversity. Low flows are problematic throughout the subbasin.