Sagging Sewage Program Traces-- Dust changes can build your drain line to sag. When this occurs, the portion which has sunk accumulates paper as well as waste resulting in a blockage.?? ? ??????????? ????? ???? ??????? ???? ??????????? ?????, ????? ?? ????? ??????? ??? ????????? ???, ?? ?????? ???? ?? ??? ?????????????.?? ??? ????? ????????? ??????