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Office of Columbia River

Columbia River Basin
Overview of Washington's Watersheds: Tier II Results

  • WRIAs
  • Results
  • Supply
  • Demand
  • Changes in Demand
  • Instream
  • Unmet Demand

Washington Watersheds (WRIAs)

Click on WRIA on map or on list below for individual WRIA results.

Clickable Image 48:
Methow 49:
Okanogan 60:
Kettle 61:
Upper Lake Roosevelt 62:
Pend Oreille 52:
Sanpoil 58:
Middle Lake Roosevelt 59:
Colville 51:
Nespelem 47:
Chelan 50:
Foster 53:
Lower Lake Roosevelt 54:
Lower Spokane 48:
Methow 45:
Wenatchee 46:
Entiat 44:
Moses Coulee 42:
Grand Coulee 43:
Upper Crab-Wilson 56:
Hangman 57:
Middle Spokane 39:
Upper Yakima 40:
Alkali-Squilchuck 40:
Alkali-Squilchuck 41:
Lower Crab 34:
Palouse 38:
Naches 37:
Lower Yakima 36:
Esquatzel Coulee 33:
Lower Snake 29:
Wind-White Salmon 30:
Klickitat 31:
Rock-Glade 32:
Walla Walla 35:
Middle Snake 29a & 29b. Wind & White Salmon
30. Klickitat
31. Rock-Glade
32. Walla Walla
33. Lower Snake
34. Palouse
35. Middle Snake
36. Esquatzel Coulee
37. Lower Yakima
38. Naches
39. Upper Yakima
40 & 40a. Alkali-Squilchuck & Stemilt-Squilchuck
41. Lower Crab
42. Grand Coulee
43. Upper Crab-Wilson
44. Moses Coulee
45. Wenatchee
46. Entiat
47. Chelan
48. Methow
49. Okanogan
50. Foster
51. Nespelem
52. Sanpoil
53. Lower Lake Roosevelt
54. Lower Spokane
55. Little Spokane
56. Hangman
57. Middle Spokane
58. Middle Lake Roosevelt
59. Colville
60. Kettle
61. Upper Lake Roosevelt
62. Pend Orielle

Washington Watersheds (WRIA) Results Summary

Clickable Image 48:
Methow 49:
Okanogan 60:
Kettle 61:
Upper Lake Roosevelt 62:
Pend Oreille 52:
Sanpoil 58:
Middle Lake Roosevelt 59:
Colville 51:
Nespelem 47:
Chelan 50:
Foster 53:
Lower Lake Roosevelt 54:
Lower Spokane 48:
Methow 45:
Wenatchee 46:
Entiat 44:
Moses Coulee 42:
Grand Coulee 43:
Upper Crab-Wilson 56:
Hangman 57:
Middle Spokane 39:
Upper Yakima 40:
Alkali-Squilchuck 40:
Alkali-Squilchuck 41:
Lower Crab 34:
Palouse 38:
Naches 37:
Lower Yakima 36:
Esquatzel Coulee 33:
Lower Snake 29:
Wind-White Salmon 30:
Klickitat 31:
Rock-Glade 32:
Walla Walla 35:
Middle Snake

WSU’s modeling provided a spatial analysis that allowed for forecasting for eastern Washington’s watershed resource inventory areas (WRIAs). Results for individual WRIAs can be found by clicking on the WRIA on this map. Detailed results are included for each WRIA, comprising a summary of supply and demand results and information on the watershed’s water management, water allocation and (for fish critical WRIAs) fish populations. The scale of modeling did not allow for results at the sub-WRIA level.

Definitions of water supply and demand are as described in “Definitions of Water Supply and Water Demand Used in the 2011 Forecast.” It is also important when interpreting results to recognize that analysis of water supplies at the WRIA level focused on water supplies generated within the Washington WRIA. For this analysis, supplies exclude upstream areas that are outside Washington, as well as the mainstem Columbia and Snake Rivers. This was done because much of eastern Washington’s water demands come from areas that cannot be hydrated by the Columbia River, but instead are supplied by the major tributaries.

In some watersheds that border the Columbia River, the mainstem supplies the majority of the water necessary to satisfy demands. In other watersheds, demands are met by supplies that come from upstream areas outside of Washington. These additional supplies are summarized elsewhere in this report. Supplies on the mainstem are summarized in the section  “Washington’s Columbia River Mainstem Tier III Results.”  Supplies in areas outside of Washington state are summarized in the section “Columbia River Basin: Tier I Results.”

Surface Water Supplies in Washington Watersheds

Flows leaving major tributary areas make sizeable contributions to the Columbia as it makes its way from the Canadian border to Bonneville Dam.  The figure below shows flows (prior to accounting for demands) from major tributary areas, including the portions of tributary areas that extend upstream outside of Washington state.  

Contribution of flows from tributaries to mainstem Columbia RiverContribution of WRIA flows into mainstem

Contribution of water supplies from tributaries to mainstem Columbia River: Top number (bold) refers to 2030 forecasted water supplies for average flow conditions. Bottom number (italic) refers to the historical (1977-2006) water supplies. All values are in cubic feet per second.

Annual surface water supply within the Washington portion of the Columbia River Basin is expected to increase for most tributaries of Washington:

    • Walla Walla (7.2 ±1.9%)
    • Palouse (5.9 ±3.6%)
    • Colville (9.5 ±2.8%)
    • Yakima (4.4 ±2.3%)
    • Wenatchee (5.9 ±1.8%)
    • Chelan (5.8 ±1.5%)
    • Methow (7.7 ±2.3%)
    • Okanogan (4.3 ±2.4%)
    • Spokane (6.6 ±2.2%)

Out-of-Stream Water Demand in Washington Watersheds

Forecast water demand for combined agricultural irrigation and municipal uses in 2030, including both surface water and groundwater demands, was concentrated within the southern and central Columbia Basin, including Lower Yakima (37), Lower Crab (41), and Esquatzel Coulee (36), as well as Rock-Glade (WRIA 31), Walla Walla (32), Lower Snake (33), Naches (38), Upper Yakima (39), and Okanogan (49) (see figure below).  These results are dominated by the impacts of irrigation water demand for most WRIAs.  Changes in municipal demands are summarized in this table.

Total average annual irrigation and municipal water demand by WRIA

Irrigation and municipal demands by WRIA

Total 2030 forecasted average annual surface water and groundwater demands for irrigation and municipal uses
(including self-supplied domestic) by WRIA (in ac-ft per year).

Changes in municipal demand for WRIAs in the Columbia River Basin

WRIA WRIA Name 2010 Population Estimate 2030 Population Estimate Population      Increase 2010-2030 Change in Diversion 2010-2030  Change in Consumptive Use 2010-2030
% (ac-ft/year) (ac-ft/year)
29 Wind-White Salmon 10,710 23,564 120.0 1,961 351
30 Klickitat 23,275 28,003 20.3 2,383 791
31 Rock-Glade 93,685 104,313 11.3 1,836 615
32 Walla Walla 58,557 71,031 21.3 2,707 2,088
33 Lower Snake 65,377 76,115 16.4 2,755 291
34 Palouse 76,661 80,224 4.6 421 595
35 Middle Snake 26,344 29,699 12.7 1,630 1,215
36 Esquatzel Coulee 27,389 44,376 62.0 9,164 5,869
37 Lower Yakima 227,594 272,268 19.6 13,356 6,986
38 Naches 68,265 83,286 22.0 2,674 2,181
39 Upper Yakima 50,387 66,206 31.4 4,919 4,346
40 Alkali-Squilchuck 11,410 11,924 4.5 189 166
41 Lower Crab 74,527 95,981 28.8 12,377 6,286
42 Grand Coulee 16,214 15,389 -5.1 -223 -113
43 Upper Crab-Wilson 14,238 14,494 1.8 145 114
44 Moses Coulee 27,805 35,047 26.0 1,320 20
45 Wenatchee 50,530 65,673 30.0 5,284 2,137
46 Entiat 6,100 7,281 19.4 146 68
47 Chelan 14,701 19,419 32.1 1,164 478
48 Methow 11,975 14,362 19.9 835 264
49 Okanogan 22,583 27,544 22.0 1,767 635
50 Foster 11,453 14,121 23.3 851 490
51 Nespelem 1,198 1,358 13.4 45 3
52 Sanpoil 4,417 5,508 24.7 310 35
53 Lower Lake Roosevelt 4,367 5,435 24.5 421 238
54 Lower Spokane 76,440 101,152 32.3 6,329 1,467
55 Little Spokane 59,097 66,716 12.9 3,069 1,682
56 Hangman 56,051 61,374 9.5 701 316
57 Middle Spokane 254,751 342,462 34.4 29,201 12,779
58 Middle Lake Roosevelt 6,498 10,079 55.1 1,049 600
59 Colville 21,394 33,414 56.2 3,520 2,013
60 Kettle 4,518 6,286 39.1 518 296
61 Upper Lake Roosevelt 9,240 14,836 60.6 3,061 2,851
62 Pend Oreille 11,799 16,079 36.3 1,537 438
  TOTAL 1,499,550 1,865,019 24.4 117,422 58,591

 

(top)

Instream Water Demands in Washington Watersheds

Bull TroutAs described in the "Overview of the 2011 Forecast," WDFW ranked fish stock status and habitat utilization, fish habitat utilization, and instream flows in 189 stream reaches in Walla Walla, Middle Snake, Lower Yakima, Naches, Upper Yakima, Wenatchee, Methow, and Okanogan WRIAs. While independent scores for each reach generated a range of results, it was determined that great opportunity to improve salmonid production exists by pursuing water acquisition in smaller, lower elevation streams with good to excellent habitat.

In addition, streams with good to excellent habitat in higher elevations or less populous areas are likely to benefit from flow augmentation, as are lower mainstems through which most stocks/species must migrate. Any flow augmentation could be helpful in salmonid restoration efforts, especially in smaller systems that have limited flow, in over-appropriated basins, or in combination with other recovery measures. Detailed results are available in the Columbia River Instream Atlas (Ecology Publication 11-12-015).

Diamond Lake

Diamond Lake

Unmet Demand in Washington Watersheds

The Forecast calculated unmet demand due to curtailment of interruptible and pro-ratable water rights for each WRIA for the historical period (1977-2006) and for the 2030 forecast. Water curtailment included interruptions in water use when instream flows are not met, in accordance with the relevant portions of the Washington Administrative code (or for Yakima, the federal flow targets and pro-rationing system). Due to data and resource constraints, the modeling of unmet demand did not consider curtailment of one water user in favor of another more senior water right holder. Unmet instream flow demands are shown in WSU's technical report (Ecology Publication 12-12-001).

Unmet demands due to curtailment of pro-ratable or interruptible rights, or to insufficient water to meet demands at the watershed scale were indicated for the historical period in the following WRIAs:

Walla Walla (WRIA 32)
Yakima (WRIAs 37, 38, & 39)
Wenatchee (WRIA 45)
Methow (WRIA 48)
Okanogan (WRIA 49)
Little Spokane (WRIA 55)
Colville (WRIA 59)

Unmet demands were forecasted to impact additional WRIAs for the 2030 forecast. This group of WRIAs includes all watersheds that include land currently irrigated as part of the Odessa Sub-area. Within the Odessa, all lands that were irrigated by groundwater in the historical period (1977-2006) were assumed to have unmet surface water demands in the 2030 forecast, due to the existing groundwater declines. Unmet demands due to curtailment or unmet surface water demands in the Odessa were forecasted for the following watersheds:

Walla Walla (WRIA 32)
Palouse (WRIA 34)
Esquatzel Coulee (WRIA 36)
Yakima (WRIAs 37, 38, & 39)
Lower Crab (WRIA 41)
Grand Coulee (WRIA 42)
Upper Crab (WRIA 43)
Wenatchee (WRIA 45)
Methow (WRIA 48)
Okanogan (WRIA 49)
Little Spokane (WRIA 55)
Colville (WRIA 59)

Frequency and quantity of modeled unmet demands are described in more detail in the section "Forecast Results for Individual WRIAs. "

 

Definitions of terms used in this Forecast

Basin-Wide Results Tier 1 WRIA Results Overview Tier 2 Mainstem Results Tier 3 WDFW Instream Results

 

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