|I want it way over there|
Things used to be pretty loose when it came to local source of supply in the early days (1945 - 1970's). It was somewhere between a nominal 1320 feet (1/4 mile) and 2640 feet (1/2 mile) - depending on where the water right was located. In the early 1980's GMD 4 felt that the local source of supply should be largely independent of distance, and more related to specific well performance. When the dust settled on our new regulation it was a combination of the two methods. By this I mean we have a nominal 1/2 mile maximum move distance that everyone gets access to. However, if the well owner wants to move farther than this, the GMD can use a Theis analysis to estimate the cone of influence developed by his or her well over a pumping season that equals the time it takes to pump the authorized water right quantity at the current tested rate of diversion. The radial distance from the well where its cone of influence is .5 feet or more drawn down is now considered it's local source of supply. To make sure these calculations are as accurate as possible, we require a well log from within 300 feet of the original well location from which the aquifer parameters (transmissivity and storage coefficient) are determined, or, a time drawdown aquifer pump test to estimate these same parameters.
The state of Kansas has never been a fan of long water right moves, so on top of all this they insisted on a maximum move distance of 3960 feet (3/4 mile) - regardless of what the Theis analysis reveals. And the new location must meet well spacing from all other wells, too.
All in all, this regulation has worked out well for us. There have been a number of people use the regulation to move a well over the 1/2 mile limit, but there have also been cases where the longer move they wanted has not been supported. Our GMD is the only area in the state at this time where a well can be moved farther than 1/2 mile - if supported by the area hydrology. For the larger wells that influence wider areas, this new regulation seems more fair than a guesstimated distance.