Investigating Pollution in the Afon Braint Tributary

The North Wales Rivers Trust recently conducted a walkover survey of a tributary of the Afon Braint in Ynys Mon. During this survey, several potential sources of pollution were identified. These included agricultural runoff from livestock farms, riverbank erosion (poaching) caused by animals, and man-made structures like culverts that can disrupt natural water flow and habitat conditions.

One significant observation was a Combined Sewer Overflow (CSO), which was discharging untreated wastewater. The discharge displayed visible signs of grey outflow, sewage-related litter, scum, algae, and sewage fungus. Following the discovery, the issue was reported to Natural Resources Wales (NRW), which led to the installation of an Event Duration Monitoring (EDM) device to track the discharge.

EDM systems are critical tools for monitoring CSO activity. They help ensure that these overflows operate in accordance with discharge regulations, particularly during heavy rainfall or storm events, when excess water is released to prevent sewage system backups. This data plays a vital role in informing future efforts to safeguard the health of the Afon Braint and its surrounding ecosystems.

After a period of weeks NWRT staff returned to site to see some noticeable improvements following interventions to remove a blockage by NRW. This case goes to show that even a single individual reporting something suspicious can make a difference to their local environment and that you can take action into your own hands.

If you witness a potential pollution incident, report it promptly to the Natural Resources Wales (NRW) Hotline at 0300 065 3000 to help protect our waterways.