On April 13, 2007, about 1110 eastern daylight time, a Consolidated Aeronautics, Inc., Lake LA-4-200, N8543W, registered to N8543W, Inc., experienced a loss of engine power and collided with power lines then the ground during a forced landing shortly after takeoff from the Sarasota/Bradenton International Airport, Sarasota, Florida. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 personal flight from Sarasota/Bradenton International Airport, Sarasota, Florida, to Bartow Municipal Airport, Bartow, Florida for a seaplane rally. The airplane was substantially damaged and the private-rated pilot sustained minor injuries, while the passenger was seriously injured. The flight was originating at the time of the accident. The pilot stated that he performed a preflight inspection of the airplane using the checklist. The main fuel tank which was full was checked for contaminants; none were found. He did not report any discrepancies associated with the engine start, and after doing so, taxied using only the mechanical fuel pump to runway 04. He performed an engine run-up and each magneto drop was approximately 100 rpm. He turned on the auxiliary fuel pump, and noted the fuel pressure was OK. He estimated the airplane was on the ground approximately 10 minutes from the time of engine start to the moment he began the takeoff. The flight was cleared to takeoff, and he gradually applied full power, noting that the airplane accelerated satisfactorily. He rotated at 60 mph and after obtaining a positive rate of climb, retracted the landing gear. The aircraft accelerated to only 65 mph instead of the usual 80 mph, and the pilot recognized that the airplane performance was low. The tower controller asked him if he was experiencing a problem, and he verified the mixture, throttle, and propeller controls were full forward. The engine then experienced a near total loss of engine power with resulting pitch-up (normal). He lowered the nose to maintain airspeed (60 mph), and after recognizing that he would be unable to land on the airport, maneuvered the airplane to land on a nearby street. While descending when the flight was approximately 30 feet above ground level, the left wing collided with a power line. The airplane then rotated approximately 90 degrees to the left, and impacted onto the road. Bystanders helped the passenger from the airplane and he (pilot) evacuated the airplane on his own. He further reported that the airplane climbed to a maximum of 150-200 feet, and there were no unusual sounds, smells, or vibrations while in-flight. The pilot further stated that the aircraft was last fueled 6 days prior, and during his preflight inspection of the airplane, the main fuel tank was full with 40 gallons of 100LL fuel. Postaccident examination of the airplane by an FAA airworthiness inspector revealed fire damage to the engine compartment and portion of the cabin. Eight gallons of fuel were drained from the fuselage tank. A post crash fire was noted in the area of the fuel filter. The fuel filter screen cover was approximately one quarter turn loose; the o-ring appeared "OK." The filter was located downstream of the fuel selector valve, and the safety wire was correct. An aluminum fuel line in the cockpit area that goes to the fuel selector valve was found to have a crack approximately 1 inch long. The line also exhibited evidence of chafing, but not through the wall thickness. The crack was not in the area of the chafing, and there was no evidence of a fuel leak from the cracked fuel line. Post-accident examination of the engine revealed crankshaft, camshaft, and valve train continuity. The fuel manifold and mechanical fuel pump were "okay." The fuel injector servo (fuel servo) inlet screen exhibited a slight amount of rust/corrosion. The spark plugs were worn but serviceable, and the magnetos sparked at all ignition leads during rotation of the engine. The air induction system was found to be free of obstructions, and the alternate air door spring was found broken. The engine was found to contain approximately 4 quarts of oil. The oil filter was clean; the element did not contain any metal.