MADRAS — A habitat conservation plan aimed at protecting several species while shielding farmers from legal liability in Oregon’s Deschutes River basin will be formally announced next week.
The federal government is expected to publish a draft of the plan on Oct. 4 and invite public comment on measures proposed to conserve the Oregon spotted frog and several types of fish.
Irrigators and a representative of the U.S. Fish and Wildlife Service discussed the proposal at a recent joint meeting of Oregon’s Board of Agriculture and Environmental Quality Commission in Madras on Sept. 26.
“We believe there’s enough water to go around, it’s just a question of how we manage it,” said Mike Britton, general manager of the North Unit Irrigation District, which supplies water to 59,000 acres in the region.
A key feature of the plan will be to release water during the winter that would otherwise remain stored in a reservoir until NUID farmers used it during the summer irrigation season.
That release of water is intended to improve stream flows that provide habitat for the Oregon spotted frog, which was federally listed in 2014 as threatened under the Endangered Species Act.
The plan also aims to help threatened bull trout and steelhead, as well as salmon species that are at risk of requiring federal protection.
“To get the river back to the natural state is key for quality and habitat,” said Martin Richards, a local farmer and chairman of NUID.
Since releasing water from NUID’s reservoir would reduce the amount available for irrigation, those farmers will instead withdraw water that would otherwise go to the nearby Central Oregon Irrigation District.
That district, in turn, will be able to transfer the water conserved by replacing open canals with pipes, thus reducing the 45% to 65% that can be lost from seepage.
The eventual adoption of the plan will allow irrigation districts within the Deschutes Basin Board of Control and the city of Prineville to obtain an “incidental take statement” allowing limited harm to protected species without facing lawsuits under the Endangered Species Act.
Another aspect of the plan is the change in the maximum and minimum amounts of water stored in NUID’s Crane Prairie reservoir.
Traditionally, the amount of water in the reservoir fluctuated between 25,000 and 55,000 acre-feet.
Under the plan, the minimum will change to about 35,000 acre-feet, to avoid low water levels, while the maximum will fall to about 48,000 acre-feet, to avoid inundating the frog’s habitat around the reservoir.
Over the long term, efforts at restoring the frog’s habitat will also have to enhance the “sinuousity” of streams — basically, the amount they meander across the landscape.
As large quantities of water were released from the reservoir over the years, they deepened the stream channel and disconnected from the ground above by lowering the water table, said Bridget Moran, supervisor of USFWS’s Bend field office. With the water flowing deeper and farther away from habitat, frog survival suffered.
“Essentially, the wetlands were cut off from the river itself,” Moran said.
Creating artificial “analog beaver dams” can increase the landscape’s ability to hold water and prompt vegetation to return to stream banks, she said.
“Our goal is to mimic the natural hydrology,” Moran said.
Aside from protected species, farmers in Central Oregon are also contending with inadequate water supplies this year.
A depleted reservoir has cut water availability to NUID irrigators by one-fourth this year, which wouldn’t be sustainable over several years, said Richards, the district’s chairman.
“Seventy percent of our water isn’t enough to stay viable,” he said.
As growers look to modernize the irrigation system — which could cost $100 million over the next decade — they expect to save water as well as preserve its quality, said Britton of NUID.
Piping irrigation canals reduces the sediment that enters drainage water and decreases the need to use herbicides to prevent weeds from blocking water flow, he said. Temperature is also lowered with quantity, helping protected species.
“More water equals better quality water,” Britton said.