Childrey Warren Water Treatment Works (WTW) Abstraction Closure

The abstraction of groundwater from boreholes at Childrey Warren Water Treatment Works (WTW) reduces base flow into the Letcombe Brook (a rare chalk stream of national ecological importance) and requires augmentation from the River Lambourn, a special area of conservation. As part of the National Environment Programme, Thames Water agreed to pull water from a more sustainable source—the Thames catchment. This required moving water from the Lark Hill reservoir with a new pipeline; however, most of the proposed work would take place in an area of high archaeological interest.

Following documentary research, our environmental services team commissioned geophysical surveys by Cotswold Archaeology to identify buried archaeological features. The goal? To select the path of least resistance for the pipeline to minimise and mitigate construction impacts. Topsoil and subsoil were stripped under close supervision, followed by full archaeological excavation. The results were beyond expectations. Exceptional late prehistoric, Roman, and Saxon burial and settlement sites were uncovered, and the finds included 26 human skeletons. The burials date from at least the late Iron Age—approximately 2,000 to 3,000 years ago—to the Saxon period up to the 11^th century AD.

All of the remains have now been removed and a programme of laboratory-based post-excavation analysis and dating is underway which will tease out the timing and detailed nature of the settlement at Childrey Warren. With this exciting series of finds taken care of, the pipe project was able to move forward, easing water abstraction impacts on Letcombe Brook and the River Lambourn.