I irrigate out of a small creek ,can pump 800-1000 gallons  through a pivot.   Corn yields  180 -220, about a 100 bu better than dryland . Soybeans  about the same as good bottom ground. Where  the pivot goes goes over bottom ground probally 10 bu better  just can not tell why the upland will not respond as well. I pumped 85 acre feet last year  it  takes a huge pond.