From The Pueblo Chieftain (Chris Woodka):
A district formed to improve Fountain Creek last week made an appeal for those with water rights to get involved in the early stages of a study to build flood control structures.
“Water rights protection is something we should do before we get into any other aspect of flood control on Fountain Creek,” Larry Small, executive director of the Fountain Creek Watershed Flood Control and Greenway District told ditch company board members Friday.
Small spoke during the annual meeting of the winter water storage program, bringing experts in to talk about the issue of public safety vs. water rights.
“We’re not working in a vacuum,” said Mark Pifher, who represents the Arkansas River basin on the state Water Quality Control Commission.
Denver’s regional Urban Drainage Authority and the city of Aspen have raised questions with the Colorado Division of Water Resources over how floodwater detention rules work in the state, Pifher explained.
State Engineer Dick Wolfe has adopted policies that say that single-site developments can hold water for 72 hours, but that regional floodwater control projects must augment any water detained with equivalent releases under a substitute water supply plan. That same principle was applied to Fountain Creek when the city of Pueblo built a detention pond behind the North Side Walmart as part of a demonstration project. The city learned it needed an augmentation plan after the project was well underway. Urban Drainage and Aspen officials are not pleased with the policy and are looking at potential state legislation to force a change in that policy, Pifher said.
Short of a blanket change that would allow the 72-hour rule to apply, the Fountain Creek district wants to study whose rights would be affected by holding back a large flood.
A study by the U.S.
Geological Survey completed last year provided solid numbers about how much water dams or detention ponds would hold back at certain points on Fountain Creek. That in turn can be applied to the flows at the Avondale gauge on the Arkansas River, which is upstream from every major ditch except the Bessemer below Pueblo Dam.
Flood stage
After Pueblo Dam went into operation 40 years ago, it was determined that flood stage at Avondale was 6,000 cubic feet per second. Floods upstream of Pueblo Dam are contained by curtailing releases to that level.
The last time flood control protection from that type of event was in 1999. Flows on Fountain Creek are measured and Pueblo Dam can be cut back to prevent that flooding from affecting Avondale as well, said Bill Tyner, assistant division engineer.
“You can have those huge flashy flows on Fountain Creek and find ways to cut back at Pueblo Dam to protect downstream communities,” Tyner said.
Reservoirs on Fountain Creek would have to perform differently, because there would not be Bureau of Reclamation staff on hand to open or shut release gates, he said.
Quenching all thirst
Several storm events that occurred in the past four years caused the Avondale gauge to top 6,000 cfs for several hours.
“Those spot events did not satisfy everyone’s needs downstream,” Tyner said.
That doesn’t matter if you’re a farmer.
“If I have 24 hours of floodwater on the Colorado Canal, I’m going to take it. I need it,” said Matt Heimerich of Crowley County.
“Those floods are the only way we get water in storage,” said Donny Hansen, president of the Holbrook Canal.
The direct rights downstream from Avondale and above John Martin Reservoir can be met with about 4,115 cfs, but storage rights on the canals total 3,631 cfs, he explained. Water rights below John Martin require another 1,534 cfs to be met.
So, all water rights below Avondale on the Arkansas River total about 9,282 cfs.
The 6,000 cfs at Avondale might be enough to satisfy all those rights, since the return flows of one ditch are reused downstream, a factor of about 1.5 times, he said.
But the envisioned dams on Fountain Creek are aimed at stopping monster 100-year floods — the type where heavy rain falls for several days. In the USGS study, a large dam or series of dams upstream of the Fountain Creek confluence would cut in half the peak flow of a 100-year flood — 44,000 cfs, or five times the amount of water needed to fulfill all downstream water rights.
The 100-year flood flow at Avondale, coincidentally, is 44,000 cfs, according to the USGS.
Moving ahead
The Fountain Creek district is not the only agency working at flood control in the Pueblo area. The Pueblo Conservancy District, in the headlines recently for its plan to rebuild the Arkansas River levee through Pueblo, also is responsible for the flood plain from Pueblo to the Otero County line.
“The high flows on Fountain Creek are a source of erosion that affects the land in our district down below,” said Bud O’Hara, a retired water engineer who is on the Pueblo Conservancy District board.
O’Hara showed graphs that point out about a dozen smaller events this year that created the potential for minor erosion events.
Farmers, on the other hand, generally like the erosion on Fountain Creek because it is part of the process that carries sediment downstream to help seal ditches. Many still grumble about the “clear water” that resulted from the construction of Pueblo Dam. In effect, it meant the erosive properties of the river were transferred downstream as more erosion occurred within ditch systems.
Abby Ortega, an engineer for Colorado Springs Utilities working with the Fountain Creek district, asked the farmers to provide suggestions for consultants to study the issue.
“We’re looking at how to build structures and not injure water rights,” she said. “We’re asking for your input.”
“I think the model we should use is the irrigation efficiency rules that was hosted by Dick Wolfe,” Heimerich responded. In that process, farmers and others affected by proposed rules guiding ditch improvements met for 18 months and were able to give immediate feedback. “It’s just too important not to do it right.”
More Fountain Creek coverage here.