Great Shefford in West Berkshire has a new £5.2 million flood alleviation scheme, completed in June 2025 and now officially launched by the Environment Agency. The project better protects 26 properties from high flows on the Great Shefford Stream and adds new habitat where the diversion meets the River Lambourn.

Engineers built a roughly 1km bypass that works automatically: a mix of underground pipeline, rectangular culverts and a short open section, finishing in a backwater to slow water and support wildlife. The design delivers biodiversity net gain alongside risk reduction.

The outlet connects with the River Lambourn, a protected chalk stream designated both a Site of Special Scientific Interest and a Special Area of Conservation. Chalk streams are globally scarce; around 85% are found in England, so habitat gains here carry national weight. Since February 2024, most developments in England are required to deliver at least a 10% biodiversity net gain, shaping the ecological features now often integrated into flood schemes.

Residents helped get this built. The Great Shefford Flood Alleviation Association raised £80,000 to unlock wider funding, West Berkshire Council supported planning, and delivery involved BAM as main contractor with Stantec on design, Advantage RSK and Binnies managing the contract, and oversight from Mott MacDonald and Jacobs.

Local voices capture the tone. The Environment Agency’s Anna Burns welcomed completion and said she hopes the scheme brings peace of mind after years of flooding. Lambourn Valley Flood Forum’s Nick Voysey said the benefits should reach the wider valley as communities face wetter winters and a changing climate.

The risk context is real. Through spring 2025 the Agency held groundwater alerts across the Lambourn Valley, including Great Shefford, with high levels leaving basements, gardens and lanes affected even during dry spells. This bypass is intended to route high stream flows safely to the Lambourn when levels rise.

Nationally, updated flood risk data show 6.3 million properties in England lie in areas at risk from rivers, the sea or surface water today, rising towards around 8 million by the middle of the century as the climate warms. Local schemes like this one play into that bigger resilience picture.

Funding has increased, but keeping assets in good condition will be the measure that matters. In February 2025 ministers added £250 million for flood defences and urgent repairs, taking two‑year spend to £2.65 billion and aiming to safeguard about 66,500 more properties by March 2026.

If you live nearby, use this moment to prepare. Register for free warnings and keep Floodline handy: 0345 988 1188. Review property‑level resilience, from non‑return valves on drains to self‑closing airbricks and flood doors; ask about standards such as the BSI Kitemark; and consult the National Flood Forum’s Blue Pages for independent guidance. Simple steps such as raised sockets and resilient flooring speed recovery after a flood.

Great Shefford shows what climate adaptation looks like when flood risk, nature and community line up. A passive channel that lowers risk and improves a chalk‑stream corridor is a modest build with outsized value. With heavier downpours expected, similar village‑scale schemes will matter more each winter.