The River Aldbourne is a pretty chalk stream, which in its upper reaches around the village of Aldbourne is a winterbourne, but nearer its confluence with the River Kennet flows all year round.
The waterbody status of the Aldbourne (2019) is moderate, with good ecology but the water is polluted with Polybrominated diphenyl ethers (PBDE). The water body status declined from Good (2016) to Moderate (2019). There is scope of further environmental habitat improvements and reduction in pollution from sewage. When ground water levels are high, the Aldbourne rises above the village which shares its name and flows through Preston and Ramsbury before joining the River Kennet near Knighton.
The Aldbourne has been subject to repeated pollution incidents caused by groundwater entering foul-water sewers causing them to overflow onto the streets and into the river. In 2010 Thames Water was fined by the Environment Agency for allowing repeated pollution incidents to occur. Thames Water has been working with the local ‘Drainage Improvement Group – ‘DIG’ to find a resolution to the problem. The most recent fish surveys on the Aldbourne were conducted in the early 1990s, and showed brown trout, grayling and pike. The assessment of ‘good ecological status’ was based on invertebrate surveys.
Actions complete: Towards the end of the reach the channel splits in two. On this section two gauging weirs were removed in Summer 2018 which has re-naturalised the river. The channel is wild and has recovered well from human interference to leave a diverse range of habitats and dense macrophyte growth. No further work is required in this section.
Actions required:
- The channel is narrow and has been over-deepened for drainage purposes as it flows through predominantly agricultural land. It would seem beneficial to install large woody debris to encourage some sinuosity and diversity, and to restrict cattle or livestock access, allowing natural recovery. Groundtruthing this will be a necessity.
- The modified reaches, particularly around the village of Aldbourne, need assessing for enhancement options.