Water to fill another 7-14 days

Post date: Oct 09, 2013 1:4:20 AM

CNPPID floodwater diversions continue, helping recharge wetlands

By LORI POTTER Hub Staff Writer | Posted: Tuesday, October 8, 2013 12:45 pm http://kearneyhub.com

GOTHENBURG — High flows in the Platte River may allow Central Nebraska Public Power and Irrigation District officials to continue diversions into irrigation canals and reservoirs for another week or longer. “I told the board maybe seven days or maybe 14,” CNPPID Civil Engineer Cory Steinke said after Monday’s Central board meeting in Gothenburg. He was diverting 2,236 cubic feet per second this morning at the district’s supply canal diversion structure just east of North Platte. Steinke said 125 cfs is going into the Phelps Canal and 300 cfs is being delivered to the E-65 Canal and Elwood Reservoir, which has risen nearly 9 feet since diversions of floodwaters originating in the South Platte Basin in Colorado began more than two weeks ago.

The irrigation canals also are delivering water to two Rainwater Basin wetlands managed by the U.S. Fish and Wildlife Service, the Funk Waterfowl Production Area and the Cottonwood WPA near Bertrand. Steinke estimated that the total delivered by Monday night would be about 800 a-f to Funk wetlands and 60 a-f to Cottonwood. An agreement approved Sept. 21 will allow up to 2,000 a-f of recharge benefits at the Funk WPA.

Floodwaters also were used to fill Johnson Lake. Now, Steinke said, most of the diverted water is being run through Central’s hydropower plants and then returned to the Platte River. “Johnson is full, so everything is pretty much going through,” he added. Steinke said that even as river flows and diversions decline, he will continue to run as much water as possible through the hydropower plants and to the Funk WPA.

River flows this morning were at 3,380 cfs at Overton, compared with 7,810 a week ago, and 3,990 cfs at Kearney, compared with 9,624 a week ago.

Recharge water costs CNPPID has agreements with the Nebraska Department of Natural Resources and Tri-Basin Natural Resources District for diversions that are recharging groundwater and ultimately will benefit streamflows.

Tri-Basin General Manager John Thorburn of Holdrege said his board originally approved payments for 7,500 a-f of diversions into the Phelps Canal for groundwater recharge, “not really anticipating that we would have the chance to use it.” If that total is reached, which Thorburn said is unlikely now because of slow seepage from the canal, the total cost would be $187,500, of which the NRD’s share is $75,000. Then, the board approved initial payments for 10,000 a-f added for the E-65 Canal and Elwood Reservoir. An agreement for another week and another 5,000 a-f was approved by the Tri-Basin board at a special meeting Oct. 1 and by the CNPPID directors at their board meeting Monday in Gothenburg.

Thorburn said the total possible recharge benefits in the Platte and Republican basins from the two canals and Elwood Reservoir is 22,500 a-f feet. He explained that the state can take credit for the benefits to the two basins under the Platte River Recovery Implementation Program and Republican River Compact, and Tri-Basin will get the same credit within the state as part of its integrated water management plans. Of the total payments to CNPPID of $802,500 for floodwater diversions, if the maximums are reached, DNR will pay 60 percent and Tri-Basin’s 40 percent share will be $321,000. “These are huge bills we didn’t anticipate when approved the budget,” Thorburn said. On tonight’s Tri-Basin board meeting agenda is consideration of fiscal year 2013-2014 budget adjustments to pay for the recharge water. Thorburn said the plan is to take money from three places: Cash reserves, an earmark for an existing agreement with CNPPID to re-purpose irrigation water rights for recharge that is awaiting DNR approval and an account for a Republican Basin augmentation project. He said that project may be started this year, but probably won’t be completed.

Measuring benefits “This obviously was a rare event,” Thorburn said about seeing such high flows in the Platte River at a time when up to 2,250 cfs could be diverted into Central’s system for several weeks. “It was an opportunity for us to do something beneficial with this floodwater and, I hope, it helped limit the flood damage.” Steinke told the Hub that measuring the flood damage benefits “is speculation in my view.” However, he said there certainly are benefits from the groundwater recharge, filling of reservoirs and water flowing into the Rainwater Basin wetlands. He plans to end diversions into the E-65 Canal and Elwood Reservoir by Oct. 15 only because the high water has delayed work on a CNPPID project to coat the canal siphon above Elwood Reservoir.

The contractor from New London, Iowa, was mobilizing to begin that $637,000 project just as the floodwaters were reaching Central’s North Platte Diversion. The CNPPID board approved agreements with DNR and Tri-Basin Sept. 21 to share the costs of delaying the project. CNPPID will pay one-third of the final costs and the other two-thirds will be covered by DNR and Tri-Basin. Minutes of a Tri-Basin’s Sept. 20 Executive Committee meeting say the bill will include $12,880 in upfront costs, plus $4,060 per day that the contractor is kept off the job.