New IMP To Aid Water Users, Compact Compliance

New IMP To Aid Water Users, Compact Compliance

Friday, December 11, 2015

Dec. 2, 2015


URNRD Board Approves New IMP

A new Integrated Management Plan (IMP) approved by the Upper Republican NRD Board of Directors may help lessen augmentation pumping and will benefit both groundwater and surface water users.

The revised IMP was unanimously approved by the Board on Dec. 1 and will become effective Jan. 15, 2016. The intent of the revisions is to implement elements of a U.S. Supreme Court ruling favorable to Nebrask; and execute provisions of an agreement between the three states party to the Republican River Compact (Nebraska, Kansas, and Colorado).


The agreement between the states will lessen stream flow augmentation pumping by giving Nebraska 100% credit for additional stream flow produced by URNRD’s Rock Creek Augmentation project in Dundy County and the NCORPE augmentation project in Lincoln County. Previously, Nebraska and the NRDs received credit for approximately 69% of augmentation water from the Rock Creek project and 54% from the NCORPE project, which required significantly more pumping than if the projects had received 100% credit. The states reached a similar agreement in 2014.


Significant, new elements of the three-state agreement provide Nebraska more time to provide augmentation water, prevents augmentation pumping during the irrigation season, reduces chances more augmentation water will be pumped than what is necessary and will lessen the administration of surface water. Kansas water users will benefit by receiving more reliable water supplies when the water is needed.


Previously, the URNRD along with the Middle and Lower Republican NRDs produced volumes of augmentation water based almost solely on State of Nebraska projections intended to assure Compact compliance. The projections are provided late in a year prior to a year when management actions are needed and contain a buffer meant to guarantee the management actions are sufficient. The conservative approach was prudent and kept Nebraska in compliance. However, if water availability conditions improved over the course of the year in which management actions including augmentation were needed, that did not lessen the amount of water produced by the NRDs.


The Compact compliance projections procedure will not change under the new IMP, but the IMP and three-state agreement allows management actions such as augmentation pumping to correspond with changing conditions. From October of the year preceding the year in which action is needed until June 1 of the subsequent year, the NRDs will augment a volume that is the lesser of two amounts: The amount needed to bring Kansas Bostwick Irrigation District’s (KBID) supply in Harlan County Lake up to 40,000 acre feet; or the total projected Compact shortfall for the year. In most cases, the lesser of the two is expected be the amount needed to bring KBID’s supply up to 40,000 acre feet.


The amount needed for Compact compliance will be lessened by the same amount of water provided to KBID. No augmentation pumping will occur over the summer. Then, in September, the State of Nebraska will assess how much additional water – if any – in addition to that pumped for KBID is needed to close any projected Compact compliance shortfall. If additional water is needed, the NRDs will have until the following April to provide it.


This new approach increases chances that the NRDs will “pump to zero” for Compact purposes instead of pumping based solely on an early, conservative projection.


Surface water users in Nebraska are aided by the arrangement because it is expected to lessen the amount of water that the State has to administer for Compact purposes, leaving more water for surface water users. Generally, augmentation projects also help surface water users because the projects, due to their ability to provide large volumes of water in relatively short periods, reduce the amount of water that would otherwise be administered away from them.


The new IMP, like the old IMP, contains an objective to reduce groundwater use within the District by 20% from the 1998-2002 baseline pumping volumes under average precipitation conditions. In lieu of objectives for additional reductions, the IMP contains an expanded “rapid-response area” where additional restrictions would be imposed if, for unforeseen reasons, the augmentation projections were not operable. The previous rapid response area included approximately 22,500 acres within the District where the Compact groundwater model shows that at least 10% of water pumped for irrigation would have instead been realized as stream flow within a 2-year period. The new rapid response area has about 42,500 acres where the model shows that at least 10% of water pumped for irrigation would have resulted in stream flow over a 5-year period.