Irrigation Expansion Limited by Economy
Published: Friday, September 4, 2026
Lyndon Kelley, water management and irrigation Educator for Michigan State University and Purdue University, discussed irrigation economics during a recent MSU Virtual Crops Discussion.
Irrigation acreage in Michigan has seen limited growth recently, with most expanded acreage happening in Branch, St. Joseph, Cass and Montcalm counties.
The economics of installation is only one factor slowing expansion.
Permits for new water withdrawals or irrigation systems will be a hot topic this year as the remaining number of permits in Michigan dwindles. Twenty percent of the state has no remaining water registrations and about one-third of the state has only one remaining water draw permit available.
"The only way to expand irrigation is to convince someone to give up a portion of theirs, or add you as an individual with their permits," Kelley said.
However, just because the permits are limited or unavailable in some Water Management Areas (WMA), it does not indicate that home or irrigation wells are in danger of drying up. It is a management tool that keeps irrigation from unmanaged growth that draws on both surface and groundwater resources. Kelley noted that most new irrigation permitting can be accomplished but will require more steps to accomplish.
Considering the recent history of low commodity crop prices, the most sustainable irrigation situations are ones that include specialty or seed crops in the rotation.
"The yield boost in corn and soybeans alone is not enough to justify the irrigation investment," Kelley said.
Adding irrigation does not automatically put a farm at an advantage to be in line for a specialty crop contract because new contracts are limited and written as near as possible to processing plants.
Kelley also noted that Michigan has tremendous potential for expanded high-dollar crop production because of Michigan's large acreage of sandy soils, which are responsive to irrigation.
In a non-drought year, a typical corn crop has a 6-inch water deficit, or about one-third of its water needs, during peak growing months, up one-half inch from two decades ago. Over an entire growing season, 16 inches of water are needed for corn, up an inch from 20 years earlier. Water needs are expected to grow another half inch during the next decade as seed varieties produce larger yields.
Rainfall data from 2010-22 shows a two to three-week period each year with the exception of drought years when there is no rain. Historical data also show that there is an increase of about 3 inches in total rainfall per year, but Kelley says the rain is more sporadic and doesn't come at the peak time it is needed by crops.
Having reliable and economical energy to power irrigation can make or break irrigation installation decisions. Electric is the most economical to operate and pumps operating on electricity are less expensive than combustion power, but three-phase electric is not available everywhere. Diesel must be at $4 per gallon to equate to a .31/kw-hrs. Even at current peak usage and cost times, electricity only costs .15/kw-hr.
Irrigation can play a large role in activating and improving the efficiency of herbicides that reduces risk of herbicide failures. It can also reduce nitrogen volatilization losses when the irrigation water adheres the nitrogen to the soil instead of a portion of it evaporating into the atmosphere.
"You also get more crop per unit of input, but it only makes sense when the income justifies the expense," Kelley said.
Current pump capacity recommendations are 5-gallon/minute/acre which can provide an inch of water every four days on 100 acres. Corn, soybeans and alfalfa all need about .25 inches of water per day; vegetable crops require slightly more. The older recommendation of 3-gallon per minute per acre still works but means that irrigation will have to begin earlier to bank water for peak plant needs during the season. Systems should also be built to consider future expansion capacity if more acres are earmarked for future irrigation.
Kelley is housed with MSU Extension in St. Joseph County, Michigan and provides water management and irrigation education for Michigan and Indiana growers. He can be reached at kellel@msu.edu or at the St. Joseph County Extension office.
Return to Top of Page