Southwest
Environmental LimitedSouthwest
Environmental Limited| London |
| 02076 920 670 |
| Exeter |
| 01392 927 961 |
| Manchester |
| 01612 970 026 |
| Bristol |
| 01173 270 092 |
This map shows the location of sewage works that are owned and operated by Welsh Water (Dwr Cymru) . The data is divided into 2 layers, that can be toggled on and off. Larger Waste Water Treatment Works (WwTW) and Smaller Waste Water Treatment Works (Small WwTW).
Note: If you click on each marker, you will be able to view asset ID, which is handy for looking things up. Like CSO performance.
Buying a House Near a Sewage Works
If you think the below paragraphs look as though they are written my a machine, then you would be correct.
Navigating the planning system within the Dŵr Cymru (Welsh Water) service area requires a nuanced understanding of both Welsh national policy and localized infrastructure constraints. Our proprietary mapping of Welsh sewage treatment works (STW) provides developers with the "True Data" necessary to assess site viability across Wales—from the industrial coastal regions of the South to the sensitive rural catchments of Mid and North Wales. Identifying the proximity of wastewater assets is the first step in managing environmental risk and ensuring that planning applications are "duly made" under Welsh regulatory frameworks.
One of the most significant hurdles for Welsh development is Nutrient Neutrality, particularly within Special Areas of Conservation (SAC) such as the River Wye, River Usk, and River Dee. Our Welsh STW dataset allows us to pinpoint exactly which treatment facility serves a proposed development and analyze its specific phosphate stripping capabilities. By understanding the permit limits of the downstream Dŵr Cymru asset, we can produce robust Nutrient Neutrality Assessment and Mitigation Strategies (NNAMS) that satisfy the stringent requirements of both local planning authorities and Natural Resources Wales (NRW).
The unique topography of Wales—characterized by steep valleys and coastal plains—presents complex challenges for Odour Impact Assessments. In valley settings, "drainage flows" of air can trap and transport odours from a sewage works along the valley floor, often affecting receptors further away than in flatter landscapes. By integrating our Welsh STW location data with localized terrain modeling and wind data, we provide precision odour contouring. This technical approach ensures that new residential developments maintain a suitable "Cordon Sanitaire," protecting future residents from loss of amenity.
Environmental permitting and planning in Wales are overseen by Natural Resources Wales (NRW), whose guidelines often differ from those of the Environment Agency in England. Our mapping supports the creation of comprehensive Foul and Surface Water Drainage Strategies that align with Welsh SuDS (Sustainable Drainage Systems) standards. By identifying the nearest Welsh Water connection points and assessing the capacity of the receiving infrastructure, we help developers avoid the "Section 106" delays that occur when wastewater impacts are not pre-emptively addressed.
Our Welsh Water dataset is a vital resource for more than just residential planning; it is essential for industrial permits and agricultural benefit statements. Whether you are managing an anaerobic digestion plant or a large-scale manufacturing facility, understanding your relationship to the Dŵr Cymru network is critical for compliance. This mapping project has become a professional-grade geospatial tool, proving SWEL’s technical capability to provide site-specific insights that generic, national-scale reports often fail to capture.