Raw sewage dumped into rivers and streams

RAW sewage has been dumped into Welsh waterways more than 100,000 times in just 12 months.

Data from Welsh Water records the number of releases into rivers and streams to relieve pressure on the sewerage network.

Part of this problem comes from the fact we have a combined sewer network. According to Welsh Water, when the sewer system is operating normally, combined sewers collect rainwater that runs off gutters, drains and roads, as well as sewage.

However, during heavy rain, more water enters the pipes than they can cope with so there is an in-built design to relieve pressure on the system called “combined storm overflows”, or CSOS, which puts the sewage straight into Welsh rivers.

Welsh Water says that without these release points, the sewerage system would back up, causing sewage to flood out in buildings, streets, highways and to come up through toilets inside people’s homes.

Estimates suggest it would cost between £9 billion and £14 billion to remove CSOS from the network and would take decades. Welsh Water says it would make water and sewerage bills unaffordable.

Data published by Natural Resources Wales (NRW) for 2020 shows that “storm” sewage was released for 3,676 hours on 270 occasions.

A spokesman for Welsh Water said: “We recognise that with environmental legislation tightening and customer expectations changing, more needs to be done. That is why we have invested over £8 million installing spill monitors on our CSOS and we will have monitors on all our CSOS where is it practicable to do so by the end of 2022.”