Dŵr Cymru Welsh Water has officially launched its interactive map which provides near real-time information about the operation of its storm overflows to coincide with the start of the UK bathing season.

The public launch follows a three-month testing period of the beta version of the map which went live on 1 February 2024.

The digital storm overflow map allows customers and water users in Wales to find out if sensor monitors on Welsh Water’s overflows indicate if they are operating, not operating or if they have operated recently (in the past 24 hours). The map is accessible on mobile and other devices.

It also provides other useful information about each asset, such as the date and time of the last recorded instance of the overflow operating and any known maintenance issues.

Welsh Water said the map launch builds on existing work it is undertaking to ensure that it is being open and transparent about the operation of its storm overflows.

The water company commented:

“However, the map does not give information on water quality because there are many things outside of the control of Welsh Water which can impact bathing and river water quality. This can include rural land run, highway run off and private sewerage systems.”

Map users will be able to see if monitors indicate if a storm overflow is currently operating (as they are designed to do during or following heavy rain) and the date/time of the last recorded instance of them operating.  However, Welsh Water also points out that the data received from the monitors is not always accurate and does not confirm if a storm overflow is operating, it only provides an indication.

Developed with the input of potential users, over a hundred individuals and organisations were consulted during the design phase of the map. Seventy participants representing regulatory bodies, open water swimming groups, campaign groups, local authorities and Welsh Government and UK Government representatives attended demo sessions.

The group were also notified of the beta version of the map going live in February, giving them the opportunity to use, test and feedback on the map ahead of its public launch.

Welsh Water’s storm overflow map currently shows storm overflow activity for the assets close to designated bathing waters, non-designated swimming sites which were identified via a Welsh Water swim survey, and shellfish sites. This approach meets Welsh Water’s environmental regulatory commitments.

More inland storm overflows are now being added incrementally to the map in batches over the coming months until all 2,300 of Welsh Water’s assets are showing by March 2025.

Steve Wilson, Managing Director Wastewater Services at Dwr Cymru, said:

“We know how important our coastal waters and rivers are to our customers, and we take our role in helping to protect their quality very seriously. Because we’re committed to being open and transparent, we want to ensure our information is easily accessible, so we have developed the storm overflow map which allows customers to see, in near real time, what a storm overflow is doing.

“The launch of this new digital map marks a major step in the sharing of information with our customers and water users in Wales and we hope that this tool will be useful, so that they can see when storm overflows are operating.