Have you ever considered how you might be causing pollution?

Pollution – it’s a dirty word but did you know you might unwittingly be the cause of foul water entering our rivers and streams through misconnections in your home or business?

Here Natural Resources Wales Environment Officer Luke Burton explains how he has been tackling misconnections in South Wales.

Most buildings constructed after 1920 have two separate sewers: The foul sewer takes wastewater - dirty water - from toilets, bathrooms, kitchens and business’ trade effluent to sewage works for treatment while the surface water sewer takes rainwater - clean water - from the roof and sends it to rivers and beaches.

If your home or business has wastewater pipes connected to a surface water sewer intended for rainwater only, it will cause pollution in rivers and beaches.

This is known as a misconnection.

The dirty water from showers, toilets, sinks, washing machines and business processes contain unpleasant concoctions including poo, pee, paper, food waste and chemicals, when there are misconnections this dirty water our watercourses causing pollution, unpleasant smells and damages plants and wildlife.

The effects of Individual misconnections can be minor but collectively misconnections have a significant impact on water quality.

Everyone deserves good water quality wherever they live, which contributes to improved mental and physical well-being but misconnections damage water quality and stop us enjoying the natural environment.

As part of NRW’s work to reduce the risk to people and communities from environmental hazards such as pollution from misconnections, I have been working with Dŵr Cymru Welsh Water and Caerphilly County Borough Council ‘s Environmental Health Department to locate and stop misconnections in the Watford Park and surrounding areas of Caerphilly.

Here dirty water from homes is flowing untreated into Castle View lake and polluting it.

It’s likely that there’s more than one property contributing to the pollution which, when combined, is having a bigger impact. The pollution may have been occurring on-and-off over a long period but might not have been previously seen, reported and then investigated.

Since this issue was reported in 2020 NRW, DCWW and the local authority have been undertaking visual checks around surface water outfalls, water quality testing at the lake, dye testing of suspected misconnected properties, CCTV surveys of the sewer network, as well as investigating other possible sources of pollution able to make its way to the lake.

Over the coming months and where it’s safe to do so, we’ll be approaching homeowners who we think are misconnected and working with them to resolve the misconnections and stop pollution entering Castle View Lake. 

Misconnections are causing pollution all over Wales. To help us stop misconnections we need you to check the plumbing in your home or business.

Please check you have the right connections in your home or business for all surface water and foul water plumbing. Visit www.connectright.org.uk for more information.

The property owner is responsible for fixing any misconnections, even if these were in place prior to owning the property but fixing the problem is often simple and inexpensive.

We can guide you through the process so it’s important you let us know if you find a misconnection. Let us know by calling us on 03000 65 3000.

Related document downloads

Misconnections Checklist WORD [144.1 KB]

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