On March 13, 2000, about 1410 hours Pacific standard time, a Piper PA-18-150, N82751, sustained substantial damage when it collided with wires near Rio Vista, California. The United States Department of Agriculture owned and operated the airplane under the provisions of 14 CFR Part 91. The commercial pilot sustained serious injuries and his observer sustained minor injuries. The public-use pest control flight departed Rio Vista for a local flight about 1330. Visual meteorological conditions prevailed and a company flight plan was filed. The pilot stated he had been maneuvering low level in an area of wind generators and power lines for 30 minutes. His ground crew instructed him to work a new area southwest of his current location. He started a slow right climbing turn in that direction, which was to the right front of the airplane. The sun was behind a cloud and he could see power lines and wind generators in his new work area. Moments later the sun came from behind the cloud and temporarily blinded him. At that instant his rear seat observer told him to "look out." He was flying up a draw and noted wires angling across his flight path. He maneuvered to avoid them, but contacted the last wire with his right main gear. When the wire snapped, the airplane fell to the ground on its right side. The pilot had the observer reach to the panel over the pilot's head and turn the master switch and generator switches to the off position. The observer assisted the pilot from the airplane. The pilot suffered a broken right collarbone, neck and back injuries, and lacerations on both legs. They contacted rescue personnel with their cell phone. Following the accident, the operator initiated a review of its pilot training program. Revisions to be explored include requiring a high altitude reconnaissance of work areas with numerous obstacles, and establishing a route of flight prior to entering those areas.