If the blockage is further down the pipe where you can't reach:
Water taking longer than usual to leave your sink, tub, or outside gully.
If you have tried the methods above and the water is still not moving, or if you suspect tree roots have penetrated your pipes, it is time to call a professional plumber or drainage specialist. They have high-pressure water jetting equipment and CCTV cameras that can locate and obliterate the problem without digging up your entire garden.
If the blockage is further down the pipe where you can't reach:
Water taking longer than usual to leave your sink, tub, or outside gully. outside drain blockage
If you have tried the methods above and the water is still not moving, or if you suspect tree roots have penetrated your pipes, it is time to call a professional plumber or drainage specialist. They have high-pressure water jetting equipment and CCTV cameras that can locate and obliterate the problem without digging up your entire garden. If the blockage is further down the pipe