A new tool for irrigators to track crop water use and evaporation is now on the Upper Republican NRD website. Near the bottom of the home page at www.urnrd.org is a tab “Weather, Real-Time Rain Amounts, ET and Water Levels” that directs users to the evapotranspiration (ET) data.

Evapotranspiration is water lost to the atmosphere through evaporation from both the ground and plant surface, along with transpiration of water from plants. The average annual ET of corn in western Nebraska from crop emergence to harvest is approximately 27”. Knowing ET can be very useful when comparing irrigation applications with crop-water demands and it can also indicate how much water crops will need in coming days. The information is particularly useful when you’re aware of soil moisture available for crop use, which is commonly known through the use of soil moisture probes.

The weather stations where ET is estimated are: One mile west of Imperial (Chase County); 5 miles north and 1 mile east of Grant (Perkins County); and 4 miles west and 11 miles south of Enders (Dundy County.) Crop coefficients developed by UNL for southwest Nebraska are applied to the ET estimated at the sites from meteorological data. ET data for all growth stages of listed crops is available on the website. The ET totals listed for each day are for the previous 24 hours – for example, .2” shown for 12 a.m. on July 6 is the total for the 24 hours beginning at 12 a.m. July 5.

Daily ET is displayed for the following crops: Corn, potatoes, soybeans, dry beans and alfalfa. ET for wheat is also calculated through June 30.

Also available on the URNRD website in the same tab are groundwater levels and hourly, daily, monthly and annual rainfall totals at 13 locations throughout the URNRD. If you have questions about the data, contact Nate Jenkins or Dwain Curtis at the NRD office, 888-883-9066.