The last two weeks provided a brief overview of the water problems and how the state arrived at this point regarding water in Kansas, especially groundwater. So what can be done to help ameliorate the difficulties faced by a declining aquifer and just as importantly how to maintain the agriculture industry and population? Keep in mind the State of Kansas is already involved in some of these.
• Retire water rights, especially where over appropriation is documented. Also provide incentives to either surrender or reduce water rights. This is already being implemented with a program initiated not long after the Governor took office. In exchange for being allowed to use as much as you feel needed based on conditions, an irrigator is allowed to use so much total water over a five-year period. The idea is to be able to withdraw more when needed and less in better years. In exchange the irrigator agrees to lower his total water right. For those surrendering water rights, a key is the ability to replace irrigated production with economically viable dryland crops.
• Increase irrigation efficiency through equipment– This can be done in a variety of ways, some not terribly popular. For overhead sprinkler systems there are variety of nozzle packages to reduce drift and place the water as close to the ground as possible depending on soil type. Proper maintenance and constant checking of the system also optimizes efficiency. One that tends to create debate is to eliminate end guns. While this will decrease the acreage irrigated, it will save water and in Kansas, end guns are often extremely inefficient. One equipment change that is expensive and requires much more intensive management is the installation of SDI (Subsurface Drip Irrigation). By placing water in the root zone evaporative losses are minimized and the total amount of irrigation water needed is greatly reduced and yields maintained. SDI would be especially efficient on ground currently under flood or furrow irrigation due to field shape or other factors. The biggest problem with SDI is the cost, followed by the greatly increased level of maintenance necessary to keep the system operating properly.
• Increase irrigation efficiency through cultural and cropping practices – This involves everything from planting dates and reducing/eliminating tillage to hybrid/variety maturity, plant population and crop selection. Drought resistant hybrids are one example of a way to save water. Another possibility is crop rotation where practical. Anything and everything that can be done form fertility to pest control to optimize the crop environment will increase water efficiency. There is a lot here and many producers are already working hard in this area.
• Irrigation scheduling – Carefully monitoring soil moisture and crop water status along with crop growth stage in combination with monitoring PET (Potential EvapoTranspiration) allows one of several computer programs to precisely determine irrigation scheduling in relation to crop needs. It still requires careful date input, checking and adjustment but works well. KanSched, a free program from K-State is an example. The most difficult part producers often have is trusting what the programs tell them.
Naturally there is more than space permits but the point is that the situation isn’t hopeless and can be addressed.