On July 11, 2004, about 1430 eastern daylight time, a Robinson R-44 II, N277MC, was substantially damaged when it struck wires while lifting off from the Beverly Municipal Airport (BVY), Beverly, Massachusetts. The certificated private pilot and passenger were not injured. Visual meteorological conditions prevailed for the local personal flight. A flight plan was not filed, and the flight was conducted under 14 CFR Part 91. According to the pilot, after a local flight over the ocean, he elected to land the helicopter near a fresh water hose at the airport, where the helicopter could be rinsed off. Once on the ground, with the engine running, the passenger exited the helicopter and proceeded to spray water on the fuselage and rotor blades. The passenger then re-boarded the helicopter, and the pilot added collective to hover taxi from the area. As the helicopter rose from the ground, the main rotor blades struck transmission wires which were directly above the helicopter. The pilot immediately set the helicopter back on the ground and secured the engine. According to a representative at a fixed based operator (FBO) at BVY, where the helicopter was based, all helicopter operations were restricted to a designated takeoff/landing area on the ramp. All helicopters based at the FBO were required to use a dolly to move from the hangar area to the designated helicopter takeoff/landing area, and air taxis were prohibited in the ramp area.