What are you doing to reduce river pollution?
Recognising the value of rivers
We believe healthy rivers are essential for people, nature and future generations, and we do not take them for granted. Since joining Get River Positive in 2023, we have been working to improve our region’s rivers through our five commitments to rivers. We are also active members of catchment partnerships, including in the Dee, working alongside others to protect and enhance these vital habitats.
The impact of our assets on rivers
Wastewater can place pressure on the environment both after it has been treated and discharged from our treatment works, and before it reaches treatment through releases from storm overflows, commonly referred to as “spills”. Storm overflows help protect homes and communities from flooding during periods of heavy rainfall and are primarily a feature of older combined sewer systems, whilst modern networks separate wastewater and rainwater wherever possible.
We want to be open about how our storm overflows operate and the improvements we are making. Event Duration Monitors are installed on 100% of our combined sewer overflows, enabling customers to view when overflows have operated in near-real time on our live map. From the assured datasets, we reduced average spill frequency across our assets by 40% in 2025, from 36.2 spills in 2024 to 21.6.
Whilst clean drinking water results in fewer pollutions than the wastewater side of our business, leaks and bursts can place pressure aquatic ecosystems through the release of chlorine and suspended solids.
Climate change is increasing the pressures on rivers and wastewater systems. More intense rainfall can increase the amount of surface water entering sewers and place additional pressure on treatment works and storm overflows. Hotter, drier periods can reduce river flows, leaving rivers less able to absorb environmental pressures.
We are continuing to plan our investment and operations for a changing climate, so that our assets and local rivers are better able to withstand, adapt to and recover from extreme weather.
Steps we're taking to reduce river pollution
We are committed to reducing our impact and you can read about our focus on reducing pollutions in our first Pollution Incident Reduction Plan. Since Hafren Dyfrdwy was established in 2018, we have recorded no serious pollution incidents, although incidents in lower categories have occurred. Protecting the environment requires continual improvement, and our ambition is to eliminate all Category 1–3 pollution incidents by 2030.
To support this ambition, we are investing across our wastewater network to reduce spills, improve resilience and support healthier rivers and waterways. Our actions include:
Find out more about what we are doing to support rivers across our region or contact us here.
Reporting a suspected pollution
If you see a suspected pollution from one of our assets please report to us promptly so that we can investigate:
Call or Whatsapp our 24-hour emergency line on 0800 085 8033.
Why isn’t Hafren Dyfrdwy building new reservoirs?
It’s something we get asked often, especially during long hot summers and droughts. Depending on where you live, the water you receive will either come from a river, boreholes, from one of our upland reservoirs or from a spring. We even import some of our water from our neighbouring water companies.
It’s good to have a range of different types of water sources. Depending on the situation, we can also swap the source of your water if we need to, keeping your taps flowing.
Whilst we aren't currently planning to build any new raw water reservoirs (untreated), we're continuing to invest in the reservoirs we already have to make sure they can provide reliable water supplies for years to come. We've been carrying out a programme of improvements across our reservoirs, helping to maintain their safety and performance.
For example, at Pendinas Reservoir we've improved the channel that brings water into the reservoir. This helps us make better use of rainfall and maintain water levels.
And we’ve been investing in other things for our region to boost water supplies. Here are a couple of examples:
For more detail on our plans, our Water Resources Management Plan is a great place to start.