Sewage suction system capable of continuously working

The utility model relates to a sewage suction system capable of continuously working, which comprises a suction pump, a water pumping pipe and a backwashing device, one end of the water pumping pipe is communicated with a water inlet of the suction pump, the other end of the water pumping pipe is provided with a first filtering part, and the backwashing device is communicated with the water pumping pipe. The water pumping pipe is further provided with a branch pipe, the pipe diameter of the branch pipe is smaller than that of the water pumping pipe, one end of the branch pipe is communicated with the water pumping pipe, the other end of the branch pipe is provided with a second filtering part, and the branch pipe is provided with a U-shaped bent section with a vertically-downward opening and a flow sensor used for monitoring the water flow in the branch pipe. And the backwashing device is also communicated with the branch pipe. According to the scheme, the U-shaped bent section is arranged on the branch pipe,