When faced with a plague of insects around a facility, plant managers in many industries might resort by reflex to the obvious remedy: Spray a chemical insecticide.If Tad Eaton thought of chemicals when confronted with clouds of flies around the biosolids drying beds at his clean-water facility in San Antonio, Texas, he must have stopped and said to himself, “Not so fast.”Eaton, manager in charge of the biosolids program at Dos Rios Water Recycling Center, owned by the San Antonio Water System, found a better way. He installed nesting boxes for purple martins, which gobble up thousands of flies every
