When a toilet, bathtub, or sink drain clogs or drain line block, it's inconvenient, but when a sewer line clogs, you've got a serious problem. Clogged, flooding, and slow-flowing drains are caused by root damage to sewage lines, which is sometimes accompanied by gurgling sounds from the bathtub, shower, or toilet. When there is a blockage in the sewer, it affects all of the plumbing fixtures in the house, and if it gets serious enough, sewage may back up into some of your drains. The majority of sewer jams are caused by tree roots infiltrating the pipes. The sewage lines' warmth and dampness are ideal for tree roots. They insert feelers into the pipes through microscopic fractures or weak joints.