Dwr Cymru Welsh Water

Sewer Blockages

Our team of sewage inspectors work to help keep our sewerage network clear. But sometimes blockages occur and can stop, or reduce, the flow of sewage through sewer pipes. 

If this happens then there is a possibility that sewage can back up in the underground pipe network and overflow from manholes in roads, in gardens, or on private land. Blockages can also lead to pollution of a river, or can even cause your toilet to overflow and flood your house. But most blockages are avoidable. Welsh Water’s ‘Let’s Stop the Block’ campaign helps reduce the cost, bad smell, stress and impact on the environmental caused by blockages by raising awareness around what to flush and what not to.

How do I know if I have a blockage?

If you notice a strong unusual smell around sewer pipe covers, or that water is very slow to drain from your toilet, then you might have a blockage. Other possible symptoms might be water seeping from chambers or manholes in your garden or overflowing from gullies next to your house.

If the blockage is on your private pipes, we recommend that you contact a reputable drainage contractor, who will be able to help you. The costs of fixing any faults on this pipework will fall to you or your home insurers.

If the blockage is on public lines then it is the responsibility of Welsh Water. Call us on 0800 085 3968 to report the blockage, or if you would prefer you can chat to us online. If you are unsure, contact us and we will investigate.