Even as you’re no-tilling, irrigation may still be a vital part of your operation in the semi-arid regions of the U.S.
If you’re irrigating a significant amount of acreage, how would your farm do if water use was mandated to be cut by 20%?
That’s the level of reduction in pumping that the Kansas Geological Survey believes would have a “significant impact on water-level declines in western Kansas” in relation to the High Plains Aquifer, according to testimony last month by KSG interim director Rolfe Mandel before the state’s House Water and Environment Committee.
The KGS recently developed a tool for potential Local Enhanced Management Area (LEMA) and Water Conservation Area (WCA) groups to quickly assess how much reduction in water-level declines will be achieved by a given reduction in pumping.
A recent article in the Garden City Telegram also revealed work being done by Kansas State University professor Bill Golden in determining the costs of transitioning from irrigated production to dryland production, and the impact that may have on farmers and rural communities.
The question he is often asked, the newspaper says, is what will happen when groundwater use is reduced. Golden’s calculations show water use could be reduced by 20% without a drop in revenue.
He asserts that models predicting a reduction in revenue from reducing water use assume farmers utilize their water at 90-95% efficiency — meaning nearly all the water applied contributed directly to yield.
Golden speculates most growers are only at about 70% efficiency, and that he’s seen reports of the same crop yields being raised in spite of a 10-inch difference in water use.
A key point here, which seems to be forgotten in the aquifer debates, is the potential for no-till practices to increase organic matter and improve soil’s ability to absorb and retain moisture. Cover crops, properly managed, can increase the building of organic matter even faster than no-tilling alone.
Several no-tillers have shared with us that improving soil health has allowed them to water crops less often. Soil-monitoring sensors and software, precision irrigation for corner arms of pivots and, in some cases, drip irrigation can improve water-use efficiency, although they certainly require some monetary investment.
Even if water reductions aren’t being mandated yet, it’s certainly being debated seriously and it’s probably best to investigate your farm’s water efficiency now and determine if improvements can be made — before it becomes a crisis.