KEARNEY -- A proposal to repurpose Central Nebraska Public Power and Irrigation District's canals from irrigation water deliveries to groundwater recharge remains on the table.
However, the parties involved have not sat at a table together to discuss the idea since it first was proposed by the Central Platte and Twin Platte natural resources districts in May 2012.
Officials of all three entities were at the Nebraska Association of Resources Districts annual meeting in Kearney Tuesday to hear an update of a pre-feasibility study done by Brown and Caldwell, the firm hired by the two NRDs to collect data and run models of possible project scenarios.
Matt Lindburg of the firm's Denver office started his presentation with a review of the basic proposal to offer incentives to CNPPID and its irrigators to convert nearly all of the district's irrigated acres from surface water to groundwater and pivot systems.
CNPPID Public Relations Coordinator Jeff Buettner of Holdrege said more than half of Central's acres already are using pivots from the canals.
Lindburg said that by converting entirely to groundwater irrigation, the E-65 and Phelps canals and their laterals could be used to hold water to recharge the groundwater mound under Central-irrigated acres in Gosper, Phelps and Kearney counties.
He said the recharge system could hold water in off seasons and otherwise be managed in ways that would use the mound more like an underground reservoir. The recharge benefits would cover the additional groundwater pumping, he added.
Also, Lindburg said, more efficient use of the water supply would allow higher streamflows at Grand Island that could roll back the river basin from an overappropriated designation to fully appropriated.
"There could be a retiming of (water) supplies so we can use the supplies that are most available at a given time," he said.
Brown and Caldwell models show that with the proposed changes, generation by CNPPID hydros would be equal to or slightly higher.
Another part of the plan would be to operate Lake McConaughy at a lower base level to maintain beaches that would enhance recreation, according to Lindburg.
He said 75 percent of all CNPPID-irrigated land already has access to wells, "so a lot of the infrastructure to do this is in place."
Lindburg estimated that about 450 new irrigation wells would be needed to give all Central-irrigated cropland access to groundwater. He said having the entire area watered with pivot systems would be much more efficient than the current surface water delivery system.
The canal-lateral system on the east end of the Phelps Canal seems to be dense enough "to deliver recharge water about wherever we want to," Lindburg said, but some new structures might be required to do the same in areas closer to Holdrege.
There would be no negative impacts to Central irrigators, he said about the first goal of the proposed plan, or to the hydropower system. However, there would be significant benefits for Platte River streamflows, especially in dry years.
One purpose for the new pre-feasibility study, Lindburg said, was to address issues raised by CNPPID officials when the proposal first was outlined. He acknowledged that a major issue still unresolved in the model is not including any long-term effects from the multi-year drought in the early 2000s.
The graphs Lindburg showed Tuesday end at 2002.
"We would like to work with Central to refine this and get some comments on some of the assumptions made," he said.
Responding to a question about whether the Central Platte and Twin Platte NRDs are working with the Holdrege-based Tri-Basin NRD that covers Gosper, Phelps and Kearney counties, Lindburg said he had not been asked to talk to Tri-Basin about the new models.
After the presentation, CNPPID's Buettner told the Hub, "It looked like they tried to address all the issues, but didn't answer all the questions."
He said it has been a struggle to get all the data and information about model assumptions requested after Brown and Caldwell's initial presentation to CNPPID officials and irrigators in 2012.
When asked where the proposal goes from here, Central Platte NRD General Manager Lyndon Vogt of Grand Island said, "I think this is just too big of an issue for the entire state to ignore."
He would like to work with CNPPID officials to do further investigation and studies. "We're very happy to visit with Central at any time on this project," Vogt said, while acknowledging that the CNPPID representatives in the room Tuesday were hearing the update from Lindburg for the first time.
Buettner said there hasn't been the "level of conversation" between CNPPID and the two NRDs necessary to develop the models.
"The assumptions they're making are things I think Central could help them out with to make them more accurate," he added.
CNPPID Board President Dudley Nelson of Axtell said his board has had no direct request to get involved.
"The only thing we hear is when we come to meetings like this," he said.