Irrigating swampland?

In a few fields around Rensselaer, you will find irrigation rigs. The one below is a couple miles west of Rensselaer along Bunkum road and is the closest to the city. You may wonder why farmers need to irrigate in in this area, which would still be a swamp but for all the drainage tiles and ditches that have been constructed.

The answer is seed corn. This area grows some of the seed that Midwestern farmers plant. None of it is processed in Rensselaer, but a lot is processed in Remington. Remington has a large Monsanto plant and someone who farms told me that DeKalb also has a facility there. There are also a number of smaller seed corn companies in the area.

The seed corn companies contract farmers to produce the corn, and sometimes a requirement to get a contract is to have irrigation equipment just in case there is a drought. Hence, the irrigation pivots are a form of insurance.
Most of what I know about irrigation comes not from this area, but from the Nevada-Utah border. Here irrigation is not insurance--it is absolutely necessary to grow anything. The water can come from a well or from a stream flowing down from a mountain. If it is stream water, the elevation difference will provide the water pressure needed for the spray. Electrical motors move the pivots, and the pivots have a way of making sure that all the parts move so that they keep the line straight. The pivots near Rensselaer spray the water from the tops. In the picture below the water is being sprayed much closer to the ground. The lower level works with alfalfa, which was what was in this field, and also reduces evaporation, which is much more important in the desert than in Indiana. (You can tell from the mountains that this is not Indiana.)
(Feel free to correct in the comments any mistakes I made. I know very little about the area seed corn companies. In part that is because they keep changing, )