Kansas has concerns that the effects of a large dam on Fountain Creek are not adequately modeled in a study of flood control and water rights that is nearing completion.
But comments from Kevin Salter of the Kansas Division of Water Resources indicate the modeling done by the Fountain Creek Watershed Flood Control and Greenway District is “reasonable” when it comes to side-detention ponds.
Kansas is an important player because its 1985 federal lawsuit over the Arkansas River Compact raised storage issues along with wells. The Supreme Court ruled in Colorado’s favor on the storage questions, but new dams would be untested waters.
“The methodology in this draft report appears reasonable to protect water rights below the confluence of Fountain Creek and the Arkansas River for the scenario involving side-detention facilities,” Salter said.
“As for the scenario to construct a multipurpose reservoir on Fountain Creek; Kansas is concerned.”
In an email to a committee looking at engineer Duane Helton’s draft report, Salter said more study is needed to look at the full impact of a 52,700 acre-foot reservoir that would include a 25,700 acre-foot pool for recreation and water supply and 27,000 acre-feet for temporary flood storage.
“Should the actual implementation of detained flood flows on Fountain Creek impact compact conservation storage Kansas would fully expect that those flows be restored,” Salter said.
Larry Small, executive director of the Fountain Creek district, said a more complete evaluation would be made of water rights if a large reservoir is pursued.
“The district will complete a full evaluation of alternatives and a feasibility study of the preferred alternative in the future before any decision is made on flood control facilities, to include multipurpose facilities,” Small said in an email reply.
Helton’s study shows there would be little impacts on water rights if flood control structures allowed a flow of 10,000 cubic feet per second to flow through Pueblo during large floods. Water would be released as quickly as possible following the peak flow.
The study discounted extremely high flows, such as the 1999 or 1965 floods, saying there would be little damage to water rights because the high volume would fill John Martin Reservoir, creating a free river.
Division Engineer Steve Witte said Kansas concerns must be treated carefully, so a new round of litigation isn’t triggered.
Witte would like the 2015 flooding to be studied. Flows on Fountain Creek exceeded the 10,000 cfs mark on three occasions during six weeks of elevated flows. John Martin Reservoir did not fill, so it would be an ideal opportunity to explore how flood storage could be administered, he said.
“I think we need to be careful in any scenario to make sure there isn’t some material depletion,” Witte said.
After the 1999 flood, when Kansas and Colorado were in litigation over the Arkansas River Compact, Kansas raised questions about how such large flows should be divided. Those issues have not been resolved, Witte said.
Another downstream party, Tri-State Generation and Transmission Association which owns half of the Amity Canal in Prowers County, said more study is needed to determine the damage if water is detained at lower flows and how water would be allocated after a flood.
The committee looking at the report, which includes some downstream farmers, Kansas, Colorado Springs Utilities, Tri-State and others, will meet again at 10 a.m. Oct. 14 at the Southeastern Colorado Water Conservancy District offices.