By Mark Waite
Nye County Water District board members were talking about a possible pipeline to Pahrump Monday, after hearing more reports warning about overpumping.
Board member James Eason, the Tonopah town manager, even inquired how much the Southern Nevada Water Authority would be paying for pipe for their proposed pipeline from White Pine County to Las Vegas.
Jim Riesterer, with Glorieta Geoscience, delivered a second draft of a water supply appraisal investigation report. He estimated the number of Pahrump residents could increase from 36,995 people in 2011 to between 46,000 to 53,000 by 2030 depending on whether a 1 percent annual population increase or 1.7 percent increase was used.
Glorieta Geoscience estimated current water use in the Pahrump groundwater basin at 14,135 acre feet per year, higher than the most conservative estimates of perennial yield of 12,000 acre feet. An acre foot is the amount of water necessary to fill an acre one foot deep, or 325,851 gallons.
There’s far more water allocated on the books. The Pahrump basin now has 21,536 acre feet of surface water rights and 56,246 acre feet of ground water rights, in addition there are 11,106 domestic wells, which could draw over 5,600 acre feet, Riesterer said, assuming each home on a well used a half an acre foot, or 162,925 gallons per year.
Pahrump has 29,288 vacant parcels of less than 10 acres, of which 19,353 parcels are less than half an acre that would be served by a utility company, leaving 19,450 lots on which wells could be drilled, he said.
Average water use has been estimated at 266 gallons per capita per day. That would mean an increase of 59 percent to 114 percent in water use between now and 2050 depending on whether a 1 percent or 2 percent growth rate is used, Riesterer said.
“What we’re looking at now are what are the alternatives to deal with existing or projected, potential water shortages?” he asked. “Countywide conservation is going to be a big key to sustainability in the future. The Pahrump basin is going to need to take some more significant action to deal with the existing and projected shortages.”
Riesterer said possible options include taking water from springs and pumping it into the valley floor where there is substantial drawdown in wells; importing water from other basins or establishing a basinwide utility district with economic incentives for conservation.
When board member Donna Lamm asked where they could import water, Riesterer suggested the Nevada National Security Site. Nye County unsuccessfully applied for water rights on the NNSS, which was formerly known as the Nevada Test Site.
Nye County geoscientist Levi Kryder said, “we started the conversation about looking at where we could import water from but we haven’t taken it to the level, is it feasible? What basins have enough water that we could do that? We haven’t gotten very far down that road yet.”
That came after John Guillory, engineer for the Nevada Division of Water Resources, delivered a report the state engineer’s office presented to the public Oct. 2 at the Bob Ruud Community Center. It warned of a potential of 8,500 new domestic wells in Pahrump, with total possible pumping of 72,343 acre feet based on usage of half an acre foot per well.
He said Pahrump in 2011 was at a 60-year low figure for pumping, about 13,300 acre feet, compared to the perennial yield of 12,000 acre feet. Water levels dropped 30 to 60 feet since the 1960s, but Guillory said some wells closer to the alluvial fan have recovered well.
“It’s heavily dependent on future growth. You have to address domestic well issues,” Guillory said.
The state engineer recommends options including retiring existing water rights; interconnecting or consolidating public utility systems; increasing the water rights required for dedication on new subdivisions; an ordinance requiring xeriscaping or importing water from other basins.
“From what I see in the management report, I see an actual crisis situation with the amount of water available in the Pahrump basin to be pumped without overdrafting,” water board consultant Walt Kuver said. “The bottom line is we have to control growth.”
He said the overdraft in the Pahrump basin can’t be ignored.
“If you look at the current rate of usage and population numbers as they increase we quickly outpace the perennial yield. It’s not a question of when, the year doesn’t matter, it’s going to happen. The water infrastructure as I call it is going to collapse. Domestic wells will start to go dry and I think eventually public water systems will go dry. In my assessment of this data there is simply not enough water, no matter who pumps it,” Kuver said.
Kuver’s estimates were more aggressive, with an average usage of 334 gallons per capita per day. If only 11 percent of the 45,000 vacant lots were developed, Pahrump would have a population of 50,000 people in 10 years and be overdrafting the basin by 50 percent, pumping 18,000 acre feet per year. Average consumption would have to be reduced by a third to 214 gallons per capita to keep water use levels steady, he said.
Kuver recommended importing water, with the only reasonably close location being the test site. He thinks achieving water conservation below 200 gallons per day per person is unrealistic without some drastic measures, which he plans to put into the water district’s response plan.
“We have to take some short-term actions, three to five years, to prevent things from getting worse while we figure out how to manage long-term and to me that includes some growth control measures now. For example, no more subdivisions, for example no more domestic wells, until we’re confident of where you can put them and have them sustainable,” Kuver said.
He recommended asking the Nevada Division of Water Resources to declare the Pahrump basin a critical management area, under the provisions of Assembly Bill 419, enacted by the last session of the Legislature but he said special legislation would be required by the 2017 session to protect the resources in domestic wells.
Former Nye County hydrologist, the late Tom Buqo, in his 2006 water resources plan, predicted most wells would go dry by 2040 with the current rate of groundwater withdrawal in Pahrump. In the past few years, the population has actually decreased with the crash in housing.
Eason questioned the estimates, noting old studies projected Tonopah to have a population of 10,000 to 15,000, which never happened; Tonopah has a population of just under 3,000 today. Eason said the population actually went down.
Eason suggested a workshop with county commissioners before considering importing water.
Water board chairman Tim McCall said, “I feel a lot of this information is misinterpreted or inaccurate. So we all have our own opinions.”
Lamm, who attempted unsuccessfully to get education on water conservation implemented in the schools, felt very strongly the information was accurate. She complained no county commissioners attended the state engineer’s presentation earlier this month.
County Commissioner Butch Borasky asked Guillory what agency issued all these water rights to make the Pahrump basin overappropriated; Guillory admitted it was his office.
Water board consultant Oz Wichman said farmers in Pahrump had a better success rate using the Desert Land Entry Act to produce fertile farmland 28 percent of the time. That coupled with the parceling of thousands of lots by Preferred Equities Corporation in the 1970s and a rapid increase in Pahrump’s growth led to what he called “the perfect storm.”