The nightmare scenario for West Slope water nerds is a "call" on the Colorado River, meaning that Colorado, Wyoming, and Northwest New Mexico are not delivering a legally required amount of water to California, Nevada, Arizona, and Utah.
If or when that happens, some water users in the three Upper Basin states will have their water use curtailed so that the Lower Basin states get their share. Water banking is a concept being proposed on the West Slope to minimize curtailment and huge water fights between holders of pre-1922 water rights, which would not be curtailed, and holders of post-1922 rights that would be curtailed.
Durango water engineer Steve Harris spoke to this at the Sept. 25 Water 101 seminar in Bayfield.
The idea started in 2008 with the Southwest Colorado Water Conservation District and the Colorado River Conservation District. Those two entities cover the entire West Slope, Harris said. The idea of water banking is "to provide water for critical uses in cases of compact curtailment."
West Slope agricultural water users would voluntarily and temporarily reduce their water use and be compensated for it. The water would go to Lake Powell to satisfy the legal requirement for the three Upper Basin states to deliver 7.5 million acre feet of water each year (averaged over 10 years for a total 75 million AF) to the four Lower Basin states and avert curtailment.
Colorado is allocated 50 percent of the water the Upper Basin states are entitled to, Harris said, so Colorado would probably have 50 percent of the curtailment if it happened.
All this is dictated by a water compact signed in 1922. It committed 15 million AF per year divvied up between the Upper and Lower Basin states. "Average flow now is around 13 million AF in the Colorado," Harris said. The result has been continued draw-down of Lake Powell and Lake Mead.
"Right now we are at around 90 million AF versus the 75 million AF over 10 years," Harris said. If the amount delivered goes below the 10 year requirement, perfected water rights before 1922 would not be curtailed. Most of that is West Slope ag water.
About half of Bayfield's and Durango's municipal water is pre-1922 rights, he said. More than 90 percent of the 1-plus million AF of pre-1922 West Slope water is used to grow grass or alfalfa hay.
Post-1922 rights include area reservoir storage, water for coal-fired power plants, a lot of municipal and industrial water, and 98 percent of West Slope water diversions to Front Range urban areas. "So they would be curtailed. But that's not going to happen," Harris said, because Front Range residents aren't going to have their water supply cut to grow hay.
"We want to set up a water bank so the pre-1922 users would set aside water for the post-1922 users. Otherwise, pre-1922 rights could be targeted for acquisition by post-1922 users," he said.
Water banking is still an idea at this point. "We don't know if the water bank will work," Harris said. Two studies have been done, one is under way, and a fourth will be conducted by Colorado State University to look at the impacts on eight small farms of full irrigation, reduced irrigation, and no irrigation.
Harris said 50,000 to 200,000 AF of West Slope pre-1922 water might be able to go into a water bank, based on land that could be fallowed. But there is concern that some other senior water right holder could take the water before it gets to Lake Powell. Also, he said, "It's very hard to measure water saved through fallowing. Every year is different."
In contrast, there is an estimated 55,000 AF of critical post-1922 municipal and industrial use on the West Slope and 295,000 AF of critical diversions to the East Slope. "The amount of pre-compact water that might be available is much smaller than the demand," Harris said. He cited another local issue: "If you don't irrigate on Florida Mesa, people don't have water wells."
An assortment of water entities in the Colorado River Basin have contributed $11 million to do demand management pilot projects to get more water to Lake Powell. Durango applied to change their water billing to "social norming," meaning how much water you use compared to your neighboors. Harris quipped that he'd pull the norm down because he made a show of removing his lawn back in the spring.
State Sen. Ellen Roberts also spoke at the seminar. "Even though we are a headwaters state, there's a limited amount of water, and if the population is going to double by 2040 or 2050, where will the water come from? ... Every direction from Colorado, there's a neighboring state that has a legal right to some of our water."
Eighty-seven percent of the state population lives between Fort Collins and Pueblo, and they like their Kentucky blue grass, she said, adding, "Kentucky is a much better place for it. ... On the Front Range, all they care about is does the water come out when they turn on the tap."
She noted the heated reaction to the bill she introduced in 2014 to limit the size of lawns in new residential developments that use water converted from ag, leaving the ag land dry. Harris initiated that idea. Roberts commented, "To feed their lawns, they need our water."
As with population, 87 of 100 state legislators also live betwween Fort Collins and Pueblo, she said. "If they don't come out here to know our world, they don't appreciate why water is so important. ... Water is our future."
Roberts gave an update on the Colorado Water Plan, which is intended to address the projected gap between water demand and supply. Community meetings on the plan were held around the state last year and earlier this year. "The number one thing we heard was the need for storage," Roberts said. "If we can't capture and hold the water we have, we are hurting ourselves." The next question is how to pay for storage projects. "That's where the fighting begins," she said.
The water plan needs more specifics on recommended actions, Roberts said. And after the Gold King spill of toxic mine waste, it needs something about water quality threats from abandoned mines.
The 470-plus page plan is being done by the Colorado Water Conservation Board and is supposed to be presented to the governor by Dec. 10. It's available on-line at www.coloradowaterplan.com.