From The Pueblo Chieftain (Chris Woodka):
Call it a wet-headed stepchild. Colorado has puzzled for years about how to account for its underground water resources, with about the same impact as water sloshing in the bottom of a precariously carried bucket. A state water plan will attempt to incorporate groundwater management, including possible aquifer storage, even though the relationship between surface water and well water is not fully understood.
“Groundwater will be a part of the state water plan,” John Stulp, the governor’s water adviser, told about 80 attendees of a groundwater conference this week. “There are a number of studies and plans that will go forward as the state water plan is developed.”
The conference, organized by the American Groundwater Trust, was designed to address policy as a follow-up to more technical reports generated from a 2012 conference.
While Colorado water rights stretch back to the mid-1800s, groundwater in the state was of little concern until more high-capacity wells were drilled in the 1950s and 1960s. It wasn’t until 1969 that well use was incorporated into the elaborate web of prior appropriation water right, explained Steve Sims, a water lawyer who once defended the state’s water rights in the attorney general’s office. But since then, a tug-of-war between the General Assembly and water courts has muddied how groundwater is treated. Non-tributary wells are regulated by a separate commission.
“What we got was a hodgepodge of rules,” Sims said. “It’s been driven by real estate developers.”
Key court cases eroded the jurisdiction of water courts themselves as well as the power of the state engineer to regulate wells, he said. The Empire Lodge case triggered a legislative fix to substitute water supply plans in 2002. The 2009 Vance case changed the way the state accounts for water produced by oil and gas drilling.
Geography also plays a part. Alluvial well regulations differ in all of the state’s major river basins, as well as in non-tributary basins. There is little scientific understanding of the relationship of groundwater levels to surface flows, other than the common wisdom that surface irrigation or flooding increase the levels, while pumping and drought decrease them. But the timing of return flows, availability of underground storage sites and long-term effects of pumping are still unknown.
“It’s not a precise science,” said Reagan Waskom of the Colorado Water Institute, which is completing a study of the South Platte basin mandated by the state Legislature in 2012. “If you had a valve and could put water back into the river when you need it, it would be great.”
More Colorado Water Plan coverage here.