FIGURE 2-11 Central-pivot irrigation systems along central Platte River. Source: Photograph by W.L. Graf, May 2003.

under irrigation has continued to expand in recent years. The Census of Agriculture shows 5,807,308 acres of land in farms in the 12 counties along the central Platte¹ in 1959. Land in farms in the same area in 1997 was 5,606,895—a reduction of more than 200,000 acres. In contrast, irrigated land more than doubled between 1959 and 1997, from 914,432 acres to 2,125,781 acres. Irrigated acreage in the region now accounts for about 38% of the land in farms, compared with less than 16% in 1959. Although a breakdown of the relative quantities of surface water and groundwater used for irrigation is unavailable, it can be assumed that the growth in irrigation is mostly through increased groundwater uses, because surface water was completely allocated by about 1930. Some of the increase may also be due to increasing efficiency of water use and an ability to spread a given allocation over a larger area of land effectively.

The importance of irrigation to agriculture in much of Nebraska is illustrated by agricultural-land prices. For Nebraska as a whole, the 2001-2002 average dryland cropland value was $798 per acre (with no irrigation potential); center-pivot-irrigated cropland was valued at $1,513 per acre,