A controversial pipeline project that would pump Colorado River water to a rapidly growing corner of Utah passed a regulatory goal and also hit a regulatory snag on the same day, prompting the state to ask the federal government to delay further decisions until the snafu is worked out.

As proposed, the Lake Powell Pipeline would cross 140 miles, top a 2,000ft mountain ridge within Grand Staircase-Escalante National Monument (as it exists now) and produce electricity in six hydropower stations as it carries water from Lake Powell on the Colorado River to a suburb of St. George, which has a booming metropolitan sprawl of 155,000 people. The possible route has not been finalized and neither has the price tag, which state estimates put somewhere between $1.1 billion and $1.8 billion.

In the closing days of 2017, the Federal Energy Regulatory Commission (FERC) approved plans to begin the project’s environmental analysis – no confusion there. But in the same notice, FERC stated that the water-transport portion of the project might not fall under the commission’s authority and could be subject to regulation by other federal agencies. This came as a surprise to groups involved in the project – thus the snafu, which prompted the state of Utah to petition FERC to pause the application process while this issue is settled.

If finally approved, Utah will sell bonds to pay for the project. Local districts that receive water from the pipeline will repay the state over a projected 50-year period.

State and district water managers promote the pipeline as a necessary – and possibly the only – solution to a looming water shortage for Washington and Kane counties, the two counties in the southwest corner of Utah. A state report from 2014 estimated that the population within the Washington County Water Conservancy District (which includes St. George and surrounding communities) will nearly triple to 370,000 by 2040. The district would receive the vast majority of pipeline water.

Washington County currently receives nearly all of its water from the surrounding Virgin River Basin. A 2014 Bureau of Reclamation study says that streamflow on the Virgin River will decline by 35 percent – and perhaps much more – in coming decades due to climate change. Meanwhile, water demand for the water district is expected to increase from 50,380 to 184,250 acre-feet per year in that same period, according to a report from the Utah Division of Water Resources. Projections show demand outpacing supply by 2028.

If implemented, the pipeline could deliver a little more than 86,000 acre feet of water a year – 82,000 acre feet to the water district and 4,000 acre-feet to the smaller, neighboring Kane County Water Conservancy District. Water needs will then be met with Virgin River water, a continuing conservation program and water from the Lake Powell Pipeline.

According to the report, the pipeline is the only water source available to cover the projected shortfall.

“This is absolutely the best way to do it,” said John Fredell, program director for the Lake Powell Project at the water district.

Opponents strongly disagree.

“This project is really not needed by the community,” said Amelia Nuding, senior water resource analyst for the Boulder, Colorado-based nonprofit group Western Resource Advocates.

“There aren’t any benefits to the project,” said Zachary Frankel, executive director of Utah Rivers Council. “There are a long list of negatives.”

Their groups believe that the communities of southwest Utah need to dramatically improve their water conservation schemes before pumping water from one of the most overused rivers in the American West.

According to a 2016 report from the Utah Division of Water Resources, the Washington County Water Conservancy District had a water-use rate of 325 gallons per capita per day in 2010. By comparison, a 2015 report by the water division in Santa Fe, New Mexico (another dry desert metropolitan area of similar size) showed a per capita daily use of about 90 gallons. The New Mexico town is noted for having some of the highest water rates and lowest consumption rates in the nation.

Barbara Hjelle, assistant general manager and counsel for the Washington County Water Conservancy District, dismisses comparisons, arguing that different communities use different metrics to arrive at per capita use figures. “It’s very challenging to do apples to apples comparisons between communities,” she said.

In 2015 the United States Geological Survey calculated domestic water use by county across the U.S, but in finer divisions. And when comparing domestic, per-capita use of publicly provided water in Washington County, Utah, they calculated 158 gallons per capita per day, while Santa Fe County (which includes Santa Fe) used 51 – still less than one-third.

Either way, the Washington County Water Conservancy District says that it has reduced per capita use by 30 percent since 2000, and plans to further reduce per capita use to 295 gallons a day (using their numbers) by 2030.

Frankel thinks the district isn’t trying hard enough. He says the first thing to do is raise water rates so people use less water. (Local rates are low compared to the rest of the region.) “You can’t price water to give it away and say you’re serious about water conservation,” he said.

Nuding agrees. “We don’t believe conservation is the only solution – but it is primary and fundamental,” she said.

Yet a new supply is exactly what the Washington County Water Conservancy District says is needed. “You are looking at a region that is completely reliant on one source of water,” said Fredell. Even using what Fredell terms “extreme conservation,” the region would not be able to pull enough water from the Virgin River Basin to meet needs in coming decades. “As you know, conservation does not create molecules,” he joked. He sees supply diversification – that is, building the pipeline – as an absolute need.

Even so, both Nuding and Frankel think much more should be done with conservation. “It’s generally always less expensive to conserve water than generate new supplies,” said Nuding.

Which raises the question of cost and the battle over numbers.

Frankel says this would be the most expensive state-funded project in Utah, “bar none.” And he believes the state may eventually balk when a final cost is floated. He points to a 2012 letter signed by 11 economists from three Utah universities that questions whether the comparatively small population of southwest Utah could pay off a $2 billion debt. They thought it unlikely, and that the debt would increase water costs and property taxes to such an extent that people might avoid moving there. Which would make it even more difficult to pay off the debt.

Fredell, however, says that studies done for the district show that increases in property taxes, hookup fees and use fees could easily cover a $2 billion price tag – or more. And he thinks locals would be happy to pay. “He’s not from this region so I don’t think [Frankel] understands real well what it means to people to have a second source of water.”

But the FERC snafu also presents a question of timing. Hjelle called the jurisdictional issue a procedural clarification. “We hope and believe it will not be a significant delay,” she said.

Fredell says that if the FERC issue is cleared up quickly and all further permitting goes very smoothly, and construction is done as quickly as possible (though at higher cost), the pipeline could be completed in as few as eight or nine years – though 10 to 14 years might be more likely.

Which is important because water shortfalls on the Virgin River Basin water supply are projected to begin around 2028.