The Independent Economic Analysis Board (IEAB) has been asked to review a proposed project to increase in-stream flows and improve fish passage in the Twisp and Methow Rivers. The focus of the review is cost-effectiveness of the project, which requires that we compare the project costs to costs of alternative approaches to increasing in-stream flows. The proposed Methow Valley Irrigation District (MVID) project was developed by MVID, the Yakama Nation, and others over the last ten years. There are several variations of the project, but all are similar. All options would exclude about 1,110 acres from the MVID surface water service area. Owners of the excluded lands would be compensated. The remaining lands would receive water from a rehabilitated surface water delivery system. During low flows, diversions from the Twisp River would cease and more water would be diverted from the Methow instead. There is still uncertainty about how and when this exchange would be accomplished.
The IEAB has reviewed published information, and initiated discussions with project advocates, researchers, and others. Based on the information available at this time, the IEAB cannot determine if the current project option, or the other similar options, are cost-effective.
Some of the reasons for being inconclusive involve the MVID project itself. Some costs are still being determined. Instream flow amounts and triggers (i.e., when diversions would cease) are still being negotiated. There is insufficient information regarding potential hydrologic effects of the proposed project. An ongoing USGS study of groundwater hydrology, including assessment of canal seepage and return flow to the Twisp River, and the study of in-stream flow needs established by the current proposal, may help to resolve these issues.
In addition, any cost-effectiveness determination requires a clear definition of the set of alternatives under consideration. The potential cost-effectiveness of the MVID proposal cannot be judged in a vacuum. In other words, against what alternatives are we considering the MVID project? At the very least, cost-effectiveness of the MVID project can be considered relative to 1) other alternatives involving MVID, 2) alternatives to improve instream flow that acquire water outside of MVID, and 3) alternatives that include other types of improvements in a larger geographic area.
The IEAB has considered one option involving MVID: water acquisition (leasing or sales) from landowners in MVID. Water acquisition could be accomplished by surface water transfers, or by paying landowners to replace surface water with groundwater pumping. A comparison of the proposed project costs to the likely costs of a water acquisition approach suggests that water acquisition might be cost-effective. However, any water acquisition involving MVID poses legal and political concerns. In the short run, water transfers from MVID are believed to be politically infeasible, at least because water rights are uncertain. The existing MVID board of directors, or the Washington Department of Ecology (WDOE), would not approve a transfer. Recent attempts to complete water transfers involving MVID have not been successful. The current MVID proposal includes what is probably the maximum feasible amount of replacement of surface water with groundwater.
Water transfers might be a cost-effective part of the project in the future. However, approval by MVID's Board of Directors will still be required. Since there is no upstream storage, it may not be possible to change the time of use to the low-flow period. MVID has an unusually high density of landowners and residences, which may increase water acquisition costs. Feasibility of water marketing may also be limited by the inefficient conveyance system. The improved conveyance system might facilitate transfers by minimizing canal leakage, improving measurement capabilities, and allowing more exchanges.
The Twisp River is subject to more adverse low flow conditions than the Methow, and much of the remaining controversy in the proposed project involves Twisp River flows. The IEAB has briefly considered the potential for Twisp River flow restoration by water acquisition from water users other than MVID. The amount of water diversion by all other water users combined is about equal to the MVID Twisp River diversion, and some of the other diversions are junior in priority, so the amount of available water may be insufficient to accomplish the biological objectives.
Finally, we cannot determine whether the MVID project is cost-effective relative to alternative projects that would help the same species within the larger Methow River basin, or the ecological province (Columbia Cascade). We have not reviewed or considered the feasibility or cost-effectiveness of such other, broader approaches. These approaches might include new upstream water storage, other types of habitat improvements, supplementation, and/or some other cooperative venture. With uncertainty involving MVID, water rights, and continued delays in implementation of major improvements, there is value in considering other options that might achieve comparable biological benefits.
- No determination of cost-effectiveness is possible at this time for a number of reasons;
- Political, legal and structural changes would be needed before water acquisition within MVID would be feasible;
- Some water acquisition may be a cost-effective part of a long-run solution.
The IEAB proposes to update the Council on these matters within one year.