Abstract: Employee #1 was moving and reinstalling concrete forms inside a very confined space that was about 4 ft by 6 1/2 ft by 9 ft high. A 20 ft high standpipe with an outside diameter of 32 1/4 in. was in the middle of the space. The standpipe was over a section of pipe that was connecting this space to a 100 ft diameter by 20 ft deep water tank. Employee #1 apparently removed some bracing, causing the standpipe to tilt over against some rebar and break the seal at the bottom. The employee was trapped. He could not get around the sides of the pipe and the top had fallen over above him. Water from the tank and the standpipe rushed in and drowned the employee.