My sister's sump pump (Zoeller in a basement sump) runs all the time and her basement has flooded more than once. When inspecting I unplugged the pump and the water stopped coming into the sump. It appears that whatever is being pumped out if being pumped back in. The discharge of the pump goes outside the building and is directed into footer tiles which leads to the city's storm sewer. When I disconnected the connection and placed the discharge into the yard, the problem was solved.
However I now noticed that when it rains the downspouts for the roof are directed into the same footer tiles, which should go out to the street. Instead it goes back into the sump pump. She had a plumber out and he rodded out the storm sewer line to the street and put a camera into the footer tiles but didnt see any breaks in the pipe. How is it possible that water from the downspouts goes into the sump instead of the street?
Any help is appreciated. We are stumped. Thanks