BOR Gila River Diversion Costs Estimated at $800M
Key Questions Remain Weeks Before Interstate Stream Commission Makes Decision
August 11, 2014
Silver City, NM – In its final Appraisal Report of Gila River diversion and storage alternatives to inform New Mexico’s decision under the Arizona Water Settlements Act (AWSA), the Bureau of Reclamation estimates project costs for a Gila River diversion, storage reservoirs, pipeline to Deming, and water treatment at approximately $800 million. The New Mexico Interstate Stream Commission (ISC) is scheduled to make a preliminary decision on whether to move ahead with a Gila River diversion project at its August 26 meeting, yet critical questions remain unanswered regarding technical, financial and environmental feasibility of the project. The Albuquerque Journal reports that ISC Director Estevan Lopez will propose postponing the preliminary decision until reports are completed.
The latest assessment available as part of the AWSA planning process, the BOR report indicates that a Gila River diversion/conveyance/storage project with a pipeline to Deming does not make economic sense. Project costs for a diversion and storage reservoirs in Sycamore and Greenwood Canyons are estimated at $600M. Factoring in pumping stations and a pipeline to Deming (BOR estimate -$156M) along with terminal water treatment (BOR estimate – $21M/facility), a Gila River diversion project with delivery of water to communities on the east side of the Continental Divide would cost at least $800M, not factoring in annual OM&R of nearly $10M, annual exchange costs of $2M, and the construction costs of terminal water storage and distribution.
As outlined in comments provided by the Gila Conservation Coalition to the BOR and ISC, several key questions remain unanswered that are critical to the ISC decision.
- The Gila River diversion project yield has not been adequately assessed. Climate change will influence the amount of water available for diversion under the AWSA. Additionally, evaporation and seepage losses from storage reservoirs could be significant. Former Interstate Stream Commission director Norm Gaume and ISC’s independent engineering consultant RJH Consultants have both provided analyses that indicate that high seepage and evaporative losses could impair project yield by 50% and in some years the water lost could equal the amount of water diverted.
- The geology related to proposed reservoirs is the most significant unknown influencing the technical and financial viability of a Gila River diversion project. According to the BOR, the ISC’s independent engineering consultant, RJH Consultants, and former ISC director Norm Gaume, the geology of soils and bedrock at storage reservoir locations will influence the technical and financial feasibility of a project. Because the soils are highly permeable, seepage losses could be significant. Locating and transporting appropriate materials to construct reservoir dams and lining reservoirs to minimize seepage could be extremely expensive and/or technically challenging.
- Financial feasibility of the diversion project remains unknown. Neither the ISC nor the BOR reveal how a Gila River diversion project can be paid for, for whom the project water is intended, and if the water users can afford to pay for the water. Available AWSA funding represents only 10 – 15% of the estimated construction costs, leaving the bulk of the costs for taxpayers and water users to cover.
- Environmental impacts of a diversion project have not been assessed. The BOR report does not provide much discussion regarding the potential environmental impacts of a diversion project. Several threatened and endangered species (i.e., southwest willow flycatcher, yellow-billed cuckoo, loach minnow, spikedace, narrow-headed garter snake, northern Mexican garter snake) would be directly impacted by a diversion project. Project infrastructure would impair a popular recreational area and destroy the natural character of the Cliff-Gila Valley.
“As it deliberates, the ISC should keep in mind that the AWSA allows New Mexico to use federal funding on non-diversion alternatives rather than diversion. Non-diversion projects represent the most cost-effective path forward to meet southwest New Mexico’s long-term water needs,” explained Allyson Siwik, director of the Gila Conservation Coalition. “Non-diversion alternatives can meet the area’s immediate water needs, can be paid for with the available funding under the AWSA and at a fraction of the cost of a Gila River diversion project. Why spend years studying a technically and financially infeasible project when we can use the AWSA funding that we have in hand to meet our water needs now?”
The final BOR Appraisal Report is available on the NM Interstate Stream Commission website www.nmawsa.org.