Well, I've run some numbers:

3 gallons of water per day per plant EQUALS, assuming a plant population of 30K, 90,000 gallons of water per acre per day. 90,000 gallons of water per acre per day is the equivalent rainfall of 3.3 inches per day. That plant may use that much water, but I don't think so, as there is no irrigation system PLUS rainfall pattern PLUS soil moisture reserve capacity that high imaginable.

I like to think we can make a pretty good corn crop on about 23" to 27" of well timed rainfall plus irrigation events on our sandy soils, from planting to crop maturity, assuming adequate soil moisture at planting. For good measure, let's say we use 25", which equals 678,850 gallons per acre per season (one inch of rain on one acre equals 27,154 gallons of water). Breaking down further, at the 30K plant population, this equals 22.6 gallons per plant over the whole season.

I imagine for 160 bushels, you would not need that many plants nor that much water, but your sols may hold enough moisture that you can have it "built up" prior to the beginning of the peak water demand time of the crop.

My cheat sheet says that water needs will vary from 20-30 inches depending on weather conditions, plant density, fertility, soil type and days to maturity. In most seasons, the amount of water needed will be about 20 to 24 inches. I don't know how to convert inches to gallons though........

Jen