1101.5.1 Detention Systems

Where a detention system is provided, the pipe leaving the detention tank shall be permitted to be reduced to the flow allowed by the Department of Environmental Protection, provided, however, that an emergency overflow shall be provided to protect the building from internal flooding. Such emergency overflow shall equal the full size of the incoming storm water flow. Such emergency overflow shall discharge the overflow outside of the building into either of the following locations:

1. The tax lot; or
2. The public sewer, provided that the overflow piping is provided with a vent, of the same diameter as the overflow piping, that terminates on the front wall of the building facing the street and no more than 2 feet (610 mm) above the sidewalk, provided further that the connection from the overflow pipe to outlet pipe of the detention tank is no more than 9 inches (229 mm) below the top of the curb level. See Figure 1101.5(1).