Crop water-usage estimates help guide irrigation schedules

Irrigation is becoming a limiting factor, not just a management decision, for growers across parts of the U.S., and early-season shortages are forcing difficult tradeoffs. In Nebraska’s Panhandle, producers in the North Platte River Valley are facing that reality, with early estimates suggesting just 30 to 40 days of irrigation water will be available this season, according to Gary Stone, a University of Nebraska-Lincoln (UNL) Extension educator in efficient irrigation water management and irrigation cropping systems.  

That could change after May 1, when the U.S. Bureau of Reclamation meets with the irrigation districts to determine the final amount of water available, he added. As a result of the current drought conditions, more growers are asking how much water is needed to grow specific crops in the region. 

“The question has not been that common in the past and has increased for this growing season due to the lack of water,” he said. 

To help Nebraska Panhandle and Eastern Wyoming growers and irrigators make water-use decisions, Stone and his colleagues are sharing estimated crop water-use requirements for the region, which were developed by irrigation specialist Dean Yonts at the Panhandle Research, Extension and Education Center before he passed away.  

“Farmers can use the information to determine which crops to grow based on the amount of water available for irrigation,” Stone said. “But that can be difficult due to the nature of the irrigation system in the valley, what crops need the water early and those that can wait and when the irrigation districts will put the water in the canal system.” 

Crop water use requirements vary with soil moisture, precipitation, temperature, wind speed, elevation and crop growth stage, making precise estimates challenging. The biggest challenge in estimating water usage for crops that are more sensitive to early water stress, such as alfalfa and sugar beet, according to Xin Qiao, an associate professor and irrigation water management specialist at the UNL Panhandle Research & Extension Center.  

“These crops would face a similar situation when they don’t have access to canal water during the same period,” he said. “For sugar beets, early establishment and development are crucial, as stress occurring early would significantly reduce yield.” 

To help producers, in April 2025 the UNL Nebraska Panhandle irrigation team released a free irrigation scheduling tool, the ACREE (Applied Collaborative Research, Extension and Education) app. The app supports irrigation management decisions across the state without requiring the installation of soil moisture sensors. However, Qiao noted the app doesn’t replace soil moisture sensors for site-specific precision. 

“The app calculates reference evapotranspiration (ET) based on weather parameters from Nebraska Mesonet weather stations (ET is already provided by the NE Mesonet), by multiplying the crop coefficient, which develops according to the growth stage they are in, you will get an estimate of crop water use,” Qiao said.