Irrigation is part of the early history of Nebraska — and the university. Water research began in the late 1800s with the first Agricultural Experiment Station Bulletin, "Irrigation in Nebraska," published in 1887.
Nebraska now has more irrigated area than any other state but determining who gets how much water is an age-old concern for irrigators, said Derrel Martin, University of Nebraska–Lincoln professor and extension specialist in irrigation and water resources engineering.
When the well is dry, we know the worth of water. Benjamin Franklin
Nebraska's irrigated area has grown continuously since statehood but expanded most substantially during the 1970s. This was due to a widespread drought, favorable economic conditions, growth oriented water policies and technological advances with commercialization of center pivots. In that decade, three times as many irrigation wells were drilled compared with any other decade.
Expansion of irrigation generated economic growth through enhanced yields, equipment investment, increased production inputs and escalating land values. However, increases in pumping prompted some disputes within the state and intensified interstate water use tensions. In several cases, disputes about water rights led to legislation and/or litigation. Some interstate conflicts involved the United States Congress and U.S. Supreme Court.
The Republican River Compact, the North Platte River Decree and Settlement, and the South Platte River Compact have created the most conflict related to irrigated agriculture, Martin said. Kansas, Colorado and Nebraska entered into the Republican River Compact in 1943 "to provide for the equitable division of the basin's waters, remove causes of potential controversy, and promote interstate cooperation and joint action by the states and the United States in the efficient use of water and the control of destructive floods."
"Equitable division of the basin's waters" caused decades of disagreements and litigation as Kansas sought to secure what it considered its share.
An interstate compact between Nebraska and Wyoming, the Upper Niobrara River Compact, apportions the water common to the two states.
Water compacts, decrees and other agreements often are re-evaluated and revised because no one can predict future water uses due to changing production practices and technological advancements — negotiators in 1943 had no idea center pivots would be invented in 1948, soon after the Compact was approved.
Nebraska established the Natural Resources District system in 1972 to focus local efforts in managing groundwater resources.
Water for irrigation comes from groundwater storage and/or water that would have been streamflow if not used for irrigation. Some Nebraskans have concerns about depletion of the Ogallala Aquifer, part of the High Plains Aquifer System. The aquifer spans six states with approximately 2/3 of the water stored in Nebraska. Water in the aquifer in Nebraska is equivalent to approximately half the water in Lake Michigan, Martin said. Studies show that statewide water storage has remained relatively stable over the last 60 years. Some areas have experienced groundwater declines while levels have risen in other areas because water diverted from rivers seeped into the groundwater.
"The overall driving issue across much of the Western U.S. is sustainability of irrigated agriculture and the interaction between groundwater and surface water," he said. "Holistic water management is a big issue in the Republican and Platte River basins."
Other uses affect water basin management, including industrial use, generation of electricity, recreation and ecosystem needs. However, irrigation consumes the majority of the water, Martin said.
Precipitation, drought and flooding also play a prominent role in irrigation. The droughts in the early-2000s and during 2012-2013 had a significant impact on Nebraska agriculture and other water users. The economic impact to agriculture was less severe than would have occurred without irrigation compared with widespread impacts during the Dust Bowl era when little irrigation occurred, Martin said.
Water research in the Institute of Agriculture and Natural Resources focuses on "the value we derive from water we use," he said, and Nebraska Extension disseminates those findings to producers and consumers.
The overall driving issue is the development of sustainability and the interaction between groundwater and surface water. Holistic water management is a big issue in the Republican and Platte River basins. Derrel Martin
New irrigation technologies abound. Creation and evaluation of technology is part of IANR's research. The UNL Water App, for example, helps farmers use soil sensors to schedule irrigation and predict the last irrigation of the year.
"Farmers invest in technology that pays," Martin said, and the university helps develop and evaluate that technology. Ag producers benefit from new knowledge resulting from the university's research, but IANR also benefits from the knowledge of Nebraska producers, Martin said. "Farmers and water managers know a lot. It needs to be a team effort as we go forward."