In a vast majority of cases, sewer line clogs and obstructions are caused by either the homeowner or by trees. In the case of the former, years of pouring grease, oil, coffee grounds, and other clog-causing food waste down the kitchen sink drain eventually causes a clog to form. Tree roots, thirsting for any moisture in our dry landscape, reach deep and wrap around your sewer line, eventually breaking into it and blocking the line altogether.