Saturday, November 01, 2008
Sandoval Aquifer Tests Show Huge Supply of Briny Water
By Rosalie Rayburn
Journal Staff Writer
Sandoval County appears to have hit it big on its $6 million water-drilling gamble west of Rio Rancho.
Testing completed this week in the Rio Puerco basin has revealed an aquifer of briny water large enough to supply a city of 300,000 people for 100 years, according to county officials.
"The implications for Sandoval County are huge," said County Commissioner Jack Thomas, who spearheaded the water-drilling project. He cited possible new manufacturing plants, jobs and economic development for communities west of the Rio Grande.
But clean water would come with a price. County officials estimate it will cost $47 million to build production wells, a water-gathering system and a desalination plant capable of producing 10 million gallons of potable water daily.
"Now we hunt for the money," said County Commissioner Donnie Leonard.
On Friday, Thomas and Leonard hosted a tour of the well sites located in the Rio Puerco Valley, about seven miles west of the Rio Rancho city limits.
Engineers from Intera, a consulting company hired by the county, pumped about a million gallons of water from one well and measured the effect on water levels and pressure in the other well.
The 30-day test enabled the Intera engineers to predict that the wells can produce 43,200 acre-feet of water a year, for at least a century. For comparison, the city of Rio Rancho, with more than 75,000 people, currently pumps about 12,000 acre-feet of water annually.
The county has spent $6 million for drilling and testing. Previous tests have shown the Rio Puerco water contains dissolved salts and minerals that make it unsuitable for domestic use without purification.
Now, county officials are confident the aquifer is large enough to justify building a desalination plant. The county has applied for a $4.6 million grant from the state Water Trust Board to design the plant. It will pursue state and federal money and might consider issuing bonds to pay for the project, Leonard said.
The water would come from three joint water claims the county has on land owned by the King Ranch, the State Land Office and Aperion, a Scottsdale, Ariz.-based developer. The claims would allow water to be drawn from a 30-square-mile area, said County Development director Mike Springfield.
Once in production, the county would act as a wholesaler, selling water to nearby communities such as Rio Rancho. It would share the proceeds with the joint claim holders.
The county drilled the wells in 2007 using money it received in return for backing a $16 billion revenue bond for Intel. One well hit water at a depth of 3,800 feet, the other at around 6,500 feet.
Under state law, the State Engineer's Office does not have jurisdiction over water at those depths.
Tests have shown the Rio Puerco aquifer is not connected with any nearby water sources.
A fault line south of the wells separates the aquifer from the Rio Grande basin and a layer of clay-rich rock separates it from water sources above, said Rob Sengebush, senior project manager for Intera.
County officials are still exploring possible uses for the by-products from the desalination plant. One possibility would be to mix the salt with sand in road construction projects, Leonard said.
Some Albuquerque-based water experts cautioned against unleashing a stampede of new development.
University of New Mexico Water Resource director Bruce Thomson asked: "What happens in 100 years? Where is the next water going to come from?"
Mark Sanchez, executive director of the Albuquerque Bernalillo County Water Authority, also urged caution.
"They need to make sure they are not propping up communities that rely on water they won't have in 100 years," he said. "Deep aquifers don't replenish themselves. There's a fixed amount of water."