In-stream flow studies to begin
Wyoming Game and Fish Department (WGFD) and state water agencies kicked off the process to study and request unallocated Upper Green River Basin in-stream water rights to benefit the Colorado cutthroat trouts’ life cycle and state fisheries.
Representatives from the Wyoming Water Development Office (WWDO) and WGFD presented the level one project at an April public scoping meeting in Pinedale to study in-stream flows and unallocated water rights from six identified stream segments throughout the basin.
“In-stream flow is a three-legged stool with WGFD and the State Engineer’s Office (SEO),” said WWDO Program Manager Chace Tavelli.
Designated critical segments
Last year, WGFD designated critical segments of six creeks – all on public lands – and asked WWDO to determine if these particular unallocated waters have sufficient naturally flowing cubic-flow-per-second (cfs) needed to improve Colorado cutthroat trout habitats during its life cycle.
WGFD requests specific in-stream flows in its biological reports to benefit its fisheries.
The WWDO contracted Consultant Mike Fuller of Hydrologic Solutions LLC to design studies of the six Upper Green River stream segments identified by WGFD.
Fuller noted the six segments include 3.55 miles of West Horse Creek, 2.75 miles of Klondike Creek, 6.39 miles of Rock Creek, 5.98 miles of South Beaver Creek, 16.44 miles of North Horse Creek, 12.77 miles of South Horse and 3.55 miles of Maki Creek.
“We have not found any water rights at these segments or above them,” Fuller said. “We did fairly thorough evaluations.”
Level one project
The project will measure “unassigned” in-stream flows upstream from any existing water diversions and water rights’ holders and look at extensive historic gauge, depth and velocity data.
“We’re not here to debate in-stream flows,” Tavelli said. “We have a statutory duty to do these studies. The water does stay in the stream.”
WGFD In-Stream Biologist Sydney McAndrews said the unallocated water could be essential for the Colorado cutthroat and fisheries.
To select segments, they moved past a private boundary or existing water right and then went upstream as far as it was reasonable in the watershed.
Fuller will measure each segment’s depth and velocity at its downstream end, compile historic and current data, past studies and reports, then make field visits in May and compile a complete hydrologic analysis to recreate streamflow within these creeks, he explained.
Fuller is also required to perform a storage analysis to meet or adjust the in-stream flow rates for the year, per WGFD.
“We will look at what types of storage would be required to meet the wate rights requirements,” Fuller said.
Tavelli emphasized permitting new water rights does not add or take away allocated water to the tributaries or the Upper Green itself.
He said irrigation and water rights holders would not be affected, as none of the in-stream flow being quantified is allocated.
“It does not impact previously existing water rights. The water stays in the river. It doesn’t get pulled out. It’s not a sum total. Only within this segment is the amount of water being requested for permitting,” he added.
Flow requests
In the case of this year’s dry winter and spring likely lowering Upper Green water flows, McAndrews said in low snow years, the flows might not be met.
“Our requests for flows are only manageable if there is enough naturally available for what we request,” McAndrews said.
“If WGFD requests 10 cfs and there’s only four cfs in the creek – that’s hydrology,” Tavelli added.
When Fuller completes the Upper Green River Basin level one hydrology analysis, Tavelli and others will review the report.
The final report will be sent to the SEO for close scrutiny, and the SEO will then hold a public meeting next year – most likely in Pinedale – to take comments and determine the status of WGFD’s water rights application.
Joy Ufford is a corresponding writer for the Wyoming Livestock Roundup. Send comments on this article to roundup@wylr.net.
