Abstract: Adapter fittings formed with an opening therethrough are inserted into a sewer manhole with the outlet opening facing an obstruction, or build-up along the sewer walls. A forwardly thrusting nozzle adapted to spray jets of high-pressure, high-temperature water or steam is connected to a hose. Alternately, a nozzle adapted to spray jets of high-pressure, high-temperature water of steam forwardly therefrom is connected to a hose and a stiffened push wand. The nozzle and hose and/or push wand are then inserted through the adapter fittings to exit from the outlet opening into the leg of the sewer with the build-up or obstruction. A hot water/steam supply connected to the upstream end of the hose provides a supply of steam or hot, pressurized water to the nozzle.