Critics, however, allege the state of Nevada is manipulating science to enable what could be the West's largest and costliest groundwater pumping scheme and is expecting stakeholders to trust a vague monitoring program to protect their interests.
"That's basically taking the future of our children and squandering it for short-term gain," argued Paul Hejmanowski, who represents the LDS Church's Cleveland Ranch in Spring Valley. "What unbridled gall."
Last year Nevada's state engineer sided with Las Vegas, finding that impacts would be tolerable and could be "managed" through careful monitoring and staged development. Jason King authorized 84,000 acre-feet to be exported from Spring, Dry Lake, Cave and Delamar valleys. This is enough water to serve about 168,000 homes.
Numerous petitioners, including The Church of Jesus Christ of Latter-day Saints and Utah counties and ranchers, are asking Estes to invalidate King's water rights rulings. After hearing two days of arguments, the judge took the matter under advisement Friday, but whichever way he rules, the dispute is sure to end up in the Nevada Supreme Court.
"Don't expect a ruling next week," said Estes, a state senior district judge. "I'm not going to get started until August. I have several trials set. However long this takes, I hope you understand I won't be dawdling."
Las Vegas says it needs this water because flows in the Colorado River, its current source, are becoming less reliable and SNWA has proposed a $15.5 billion pipeline from these valleys and Snake Valley, a Utah agricultural region neighboring Spring Valley.
Many have framed SNWA's proposal as a "water grab" that pits Las Vegas' insatiable drive to grow against rural communities' desire to survive.
"This is anything but a good project, it is hugely threatening. It represents a permanent removal of the most important resource from this area," said Simeon Herskovits, who represents a diverse group of petitioners. "There's an obvious imbalance in this case. SNWA is not just the 800-pound gorilla. It is the 800,000-pound gorilla that overwhelms everyone and every agency it comes in contact with."
In court, the two sides accused each other of distorting administrative records made during a six-week hearing before King, contained in 20 boxes.
"The state engineer took a hard look at these basins and based his decisions on the evidence that was presented," Deputy Attorney General Bryan Stockton said. The petitioners "are taking the extreme position, if you don't have perfect knowledge you can't go forward. It is our position that pumping of water will provide more certainty."
SNWA and state lawyers claim Vegas can import water without hurting ranchers and the environment because the water the city has been authorized to develop is flowing away and evaporating without being put to "beneficial" use.
King's water rights rulings cover nearly all the groundwater he determined was available from these valleys, awarding SNWA the unappropriated portion of their "perennial yield," that is, the amount by which the aquifers are recharged every year. How that yield was calculated is the subject of intense dispute.
The plants sucking up groundwater are greasewood, rabbitbrush and other phreatophytes with long roots that tap deep water and release it into the air through a process called evapotranspiration. King concluded that if groundwater pumping disrupts this process, 34,000 acre-feet could be added to what Vegas is permitted to pump from Spring Valley, according to Hejmanowski.
The phreatophytes will die after the depth to water exceeds 10 meters. If the water level drops gradually, the phreatophytes will be replaced with other vegetation that doesn't require access to groundwater, Taggart explained.
"Slow staged development allows transition of the plant community in a healthy way," he said."The state engineer struck the right balance."
Lawyers for tribes and local ranchers ridiculed this reasoning.
"The concept that this water is lost and subject to capture completely ignores that people rely on those plants and springs," said Scott Williams, representing the Confederated Tribes of the Goshute Reservation. "To say that environmental devastation won't occur is a failure of logic."