By Larry Dreiling.
Western Kansas Groundwater Management District No. 1 was the focus of attention July 9 during a meeting, in Colby, of the Kansas Water Authority's Ogallala Aquifer Technical Advisory Committee.
GMD No.1 is being used by the committee as the basis of a pilot study on what could lead to a "two-pool" concept on managing the aquifer.
According to a concept paper produced by the KWA staff, the two-pool idea is based on the premise that the remaining water supply in the Ogallala can be divided into two separate volumes.
One volume, the conservation pool, would be based on the recharge rate, plus any additional volume necessary for the water to sustain communities and the environment. The annual recharge is that portion of the annual precipitation that seeps down through the soil into the groundwater.
This small pool of water renewed each year by recharge is a supply that could sustain communities forever, if annual pumpage remained less than the annual recharge minus the stream outflows.
The other, much larger pool of water, the usable pool, is the remaining quantity that will be depleted over time. It is stored in the aquifer and eventually will be used up within some period of time--depending on the level of use.
The technical committee met to develop a method of measurement of the depths of vested water rights and how they relate with the conservation pool within specific areas--called sub-units--of the aquifer.
The committee is comprised of producers, public officials and technical staff, from entities ranging from the U.S. Geological Survey to Kansas State University Research and Extension personnel.
The committee, part of a larger task force on the future management of the aquifer, has been charged with developing parameters for a simulated trial in GMD No.1 on development of the two pools.
The KWA's Ogallala management advisory committee had previously decided to use GMD No. 1 for the pilot study area. It now is up to the task force's technical committee to come up with specific ideas.
For more than four hours, the committee examined more than 40 possible parameters to study, along with a criteria for sub-unit selection.
"We want to make sure we are doing this right," said Al LeDoux, director of the Kansas Water Office. "We also want to make sure that producers know this only is an exercise into seeing what we may eventually do with this plan. We have no intention of shutting down anyone's well or anything like that."
LeDoux pointed out the simulation was needed, because of the high number of parameters. He said it was more than likely that a set of parameters for measuring the conservation level in one area may not work for the level in another.
"That is why GMD No.1 is a good model. It has a lot of variables to it," LeDoux said. "We can use those variables to our advantage to develop a proposal that can work to benefit everyone."
The committee left the decision on the location of sub-units up to Kansas Water Office staff. They will select existing test wells throughout GMD No. 1 to conduct tests on at least two parameters: Saturated thickness, which is the point beneath bedrock where it is no longer moist, and recharge.
Other parameters likely will be eventually used in conjunction with these initial tests to develop a body of data, which can be used for measurement purposes.
"One of the things we want to make certain of is the accuracy of our measurements," LeDoux said. "When you use one section of data, it has to have a measure of certainty with another."
The committee is set to meet again Aug. 2 to review the test material. It is supposed to file a full report on its management proposal in October or November.