Although center pivot sprinkler irrigation (CP) is the predominant irrigation method in the US Great Plains, there is growing interest in the use of subsurface drip irrigation (SDI). Pressurized irrigation systems, in general, are a costly investment. Producers need to carefully determine their best investment options. In 2002, Kansas State University developed a free Microsoft Excel template to compare the economics of center pivot sprinkler irrigation and subsurface drip irrigation for field corn (maize) production.
This template has been updated annually with new input and revenue costs and assumptions. Important factors that have always affected CP and SDI competitiveness are field size and shape suitable for center pivot sprinkler irrigation and longevity of SDI system allowing longer amortization of its greater initial cost. The primary factors that allow SDI to have greater economic competitiveness than was the case in 2002 are greater corn yields and corn price. Using the base assumptions in the template for a square 160 acre field, an SDI system lasting at least 11 years can be cost competitive with a center pivot sprinkler with a life of 25 years.