Authorities searching the Red Rock reservoir have recovered the body of a drowning victim and identified the woman who died in a mishap on the lake yesterday. The Department of Natural Resources’s Kevin Baskins says searchers who returned to the lake found the body of 47-year-old William Nelson of Urbandale near the spot where he was last seen. They weren’t divers, just patrol boats that were out and found the man’s body near where he’d disappeared, about a mile from the Mile Long Bridge on the lake’s southeastern end. He explains searchers use G-I-S, Geographical Information Systems technology to lay out a grid for searching methodically. There are also formulas to help predict when a body will resurface. Nelson had been boating with his 8-year-old son on Monday when he got into the water, possibly to cool off, and vanished under the surface. Then on Tuesday an Arkansas woman died while riding a “kneeboard” being pulled behind a speedboat on the lake. The woman, Kim Russell, died of an impact to her chest according to the autopsy. She’d “wiped out” while riding the board and the board struck her a fatal blow. That one will be classified as a boating-related mishap in the state’s records. And some pleasure boaters suffered a mishap when they followed too closely behind the wake from a historic paddleboat steaming up the Mississippi yesterday.A wave went over the bow of their boat, capsizing it. After they’d managed to swim to the shore, one of the boaters slipped on rocks on the shore, suffering a head injury. The boater was hospitalized in Dubuque