Diversion to Cost at Least $350 Million, but Many Critical Questions Unanswered
January 17, 2013
More than 150 people from the Cliff-Gila Valley and Silver City area packed the bleachers in the Cliff High School Gymnasium Monday night for the New Mexico Interstate Stream Commission’s (ISC) quarterly public meeting to hear the latest information on Gila River diversion proposals being considered under the Arizona Water Settlements Act (AWSA). (Silver City Sun-News article)
Key Points from Gila River Diversion Proposal
Costs of the Gila River diversion project are estimated to be $350 million to $450 million while the federal subsidy available under the AWSA amounts to only 30% – 40% of the total capital cost, leaving a shortfall of more than $200 million to $300 million. Most importantly, these analyses still underestimate project costs, since they do not include the costs of terminal storage, distribution, and water treatment, costs of infrastructure to access water from Sycamore Canyon, the exchange costs (about $2 million annually and rising) that must be paid to Arizona for using Gila River water in New Mexico, and as much as 6,140 acre-feet per year of evaporation that would have to be paid for.
The diversions analyzed extend from the vicinity of the Turkey Creek confluence with the Gila River through the Cliff-Gila Valley to the most downstream storage reservoir located in Dix Canyon, 2 miles south of Highway 180. Proposals also include a pipeline to Deming, as well as reservoirs capable of storing up to 65,000 acre-feet of water in multiple side canyons, requiring significant rerouting of Highway 211 and some county roads.
Diversion sites are located below Turkey Creek and above the Gila Valley. The recommended diversion would have a concrete structure across the river that would divert river water into a 9 foot-diameter pipeline blasted through the mountains or through 22-foot-wide open canals constructed along both sides of the river. Water would be piped to storage reservoirs at the upper end of the Cliff-Gila Valley in Winn Canyon and below the Highway 211 Bridge in Pope Canyon, and below Highway 180 in Sycamore and Dix canyons with the bulk of the water going to Sycamore Canyon, downstream of the Gila Valley.
Gila River water piped to Pope Canyon (approximately 16,000 acre-feet) would be pumped through a 36-inch pipe out of the Valley over the Continental Divide and then on to Deming.
The Bureau of Reclamation also presented some preliminary benefit and cost estimates of diversion and non-diversion projects. Although several benefit and cost categories are still to be included, the analysis to date shows that the costs of the diversion proposals are greater than the benefits.
Additionally, BOR identified a number of threatened and endangered species and cultural resources that are found in areas which could be impacted by potential diversion projects. More analyses would need to be conducted during the NEPA phase if New Mexico chooses to move forward with a diversion project. The diversion project will also have to comply with the Endangered Species Act.
Significant questions remain unanswered. Despite several attempts to get a response from ISC staff regarding who will pay for this water and how the shortfall in construction costs over the available federal subsidy would be covered, the ISC offered no plan for how the diversion project could be financed or who the end users are for the project water and if they can pay for it.
The ISC staff will update ISC commissioners on their analyses at the next ISC meeting on January 21 in Santa Fe. The ISC is also on the hook to report to the New Mexico legislature during the upcoming session. This is the last opportunity for the legislature to weigh in on the AWSA decision before the Secretary of the Interior is notified of New Mexico’s decision on whether it will construct a diversion or implement non-diversion alternatives to meet southwest New Mexico’s future water needs.
The next quarterly AWSA public meeting is scheduled for April.