The Idaho Department of Water Resources could begin measuring groundwater use in the region shown above. No restrictions have been proposed, but experts say the proposal brings the area one step closer to conjunctive administration of water rights. Courtesy graphic
The Idaho Department of Water Resources could start measuring groundwater use in the Big Wood and Little Wood river basins, a step toward beginning conjunctive administration of water rights in the region.
"It's an initial step," said Allan Merritt, Southern Region manager of the Idaho Department of Water Resources.
The department has proposed creating a water measurement district stretching from north of Ketchum to areas south of Fairfield. The easternmost boundary would include Picabo but not nearby Carey in the district.
Conjunctive administration of water rights would combine management of surface water rights, where water is taken from rivers, reservoirs and canals, with groundwater, which is pumped up through wells.
Currently, surface-water rights may be cut off in times of water shortage, even as junior groundwater rights are unaffected. Conjunctive management would allow holders of senior water rights, whether ground or surface, to retain top priority when it comes to water use.
While the department currently measures and administrates surface water rights throughout the region, Merritt said the same is not true of groundwater.
"There are some wells measured, but not all wells," he said.
Creation of the district would require well users to measure the amount of water they use, though the district wouldn't enforce any regulations on that water use—yet.
"It could set up an infrastructure to spring from to create a water district for the wells," Merritt said.
A water district differs from a water measurement district, which is currently being proposed, in that a water district has a water master who can shut off use if water runs short. According to a 2007 report from the U.S. Geological Survey, flows in the Big Wood River have been declining over time, making conjunctive management necessary as groundwater impacts the aquifer that the river draws from.
Dave Tuthill, former director of the department and founder of Boise-based Idaho Water Engineers, said that although a water measurement district is not required before conjunctive administration is implemented, creation of it would allow groundwater users to plan for future regulation.
"The writing is on the wall that at some point in the future, rules will be in place," he said.
Conjunctive administration was set to be implemented in the Big Wood River Basin under the state's Comprehensive Aquifer Planning and Management Program starting this year. Staff and funding shortages have delayed the project, but Tuthill estimated that a plan for administration could be in place by 2014.
"If we continue to enjoy good water years, there is not as much pressure on the administration to implement conjunctive management," he said.
The department will hold a hearing on the creation of a groundwater measurement district on Tuesday, Aug. 16, at 6:30 p.m. at the Wood River Middle School on Second Avenue North in Hailey.
Katherine Wutz: email@example.com