chachachet: they're plumbers who specialize in cleaning drains and sewer lines. They use a long drain snake, push it through the drain (or vent on the roof), and send it through the pipes to unclog the drain.

in my case, it was getting rid of the roots that were causing a backflow of water onto my laundry room floor

skipz: it is finished! The water is flowing! It is finished! There'll be no more mess!