Hamble Brook

A peaceful countryside scene at sunrise featuring a small stream winding through lush green vegetation. Warm golden sunlight illuminates the landscape, with mist rising from the water. A wooden fence and gate are partially visible on the left, surrounded by trees and tall grasses, enhancing the tranquil atmosphere.

Hamble Brook

Lead organisation

Partner organisations

Project description

The Hamble Brook project has transformed one of the Chilterns’ winterbourne chalk streams, reinstating natural form, function, and connectivity to a river system untouched for more than 140 years. Over 18 months, a collaborative team of landowners, the Chilterns Chalk Stream Project (CCSP), the Environment Agency, National Trust, and contractors worked hand-in-hand to deliver the UK’s largest winterbourne restoration to date.

The work has re-naturalised 1,100m of chalk stream and 200m of connecting channels, reshaped online and offline ponds, removed two former weirs, and created two backwater sites. The project also delivered 2,500m² of new wetland, planted 60 native trees, and improved 400m of riparian connectivity. Seven MoRPh survey sites have been established, and links with Nottingham Trent University are supporting ongoing dry-bed monitoring.

Enabled by Heritage Lottery Green Recovery Challenge Fund support, the project leveraged £3 for every £1 of grant funding, demonstrating the power of partnership working. These efforts have already paved the way for feasibility studies on a larger downstream section of Hamble Brook, promising an even greater impact in the future.

The Hamble Brook restoration has been a journey of vision, planning, and hands-on delivery:

  • Mid 2020: First conversations with the landowner sparked the idea for restoration.
  • January 2021: An advisory report outlined the potential for transforming the chalk stream and its corridor.
  • April 2021: An application was submitted to the Heritage Lottery Green Recovery Challenge Fund to secure funding.
  • Mid 2022: The tender process began to select the design and build contractor.
  • March 2023: All necessary permissions were secured, clearing the way for work to begin.
  • March–May 2023: Channel restoration works were carried out, re-naturalising the stream and improving connectivity.
  • October–Decembber 2023: Wetland creation and native tree planting brought the surrounding habitats to life, completing the transformation.

This phased approach combined careful planning, collaboration, and on-the-ground action, delivering a landmark chalk stream restoration that will be monitored and celebrated for years to come.

Project location

Hamble Brook winds through the southern Chilterns National Landscape between Henley-on-Thames and Marlow. The project focused on a rural stretch between Pheasants Hill and Skirmett, a classic chalk stream corridor wholly contained within the Big Chalk programme area.

Contribution to Big Chalk

By restoring the stream’s natural form, the Hamble Brook project has recreated a diverse habitat mosaic capable of supporting a wider range of species, including winterbourne specialists. Clean gravels, deeper pools, and wetlands will provide refuge and breeding sites for birds and aquatic life, while a balanced sun-and-shade regime supports temperature control and species migration.

Coupled with a grazing and management plan, these works ensure the chalk-stream character is not only restored today but resilient for the future, even through dry periods. A comprehensive monitoring regime—expanding beyond MoRPh and Riverfly surveys—will track how channel, wetland, and grassland species respond over time, offering vital data to inform further landscape-scale nature recovery across the Big Chalk area.

Hamble Brook stands as a landmark example of what partnership, ambition, and science-led restoration can achieve—bringing a chalk stream back to life for people, wildlife, and the wider landscape.

A group of children in bright yellow safety vests and blue shirts stand in a shallow stream, holding nets and buckets as part of an outdoor educational activity. Two adults assist them—one with a net on the left and another with a white bucket on the right. The area is surrounded by lush green vegetation.
Five people stand in and around a shallow stream surrounded by lush green vegetation. They appear to be conducting an environmental or scientific activity, with one person using a net in the water and others handling various tools. Trees and a wooden fence are visible in the grassy background.
A clear, shallow river winds through a lush green landscape, with pebbles and aquatic plants visible beneath the water. Tall grasses, bushes, and dense vegetation line both sides of the river, with trees in the background under a partly cloudy sky.
A small, weathered wooden bridge with railings sits in the middle of a grassy field dotted with wildflowers. Rolling green hills stretch into the background under an overcast sky with thick clouds, creating a muted, tranquil atmosphere.
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Do you have a project that could strengthen the future of southern England’s iconic chalk and limestone landscapes?

The Big Chalk programme brings together a dynamic suite of partner-led projects, each unique in its focus, area, and partnerships but sharing a commitment to our collective vision.

If your project contributes to the Big Chalk mission, we invite you to register it as a Big Chalk Project. Registered projects gain access to networking, shared learning, and best practice—alongside the Big Chalk brand, boosting your profile and connecting you to a powerful, growing network of partners.

Together, these projects form a united effort to secure the future of southern England’s chalk and limestone landscapes, making a lasting impact for nature and communities.

Register your project
By Adrian Porter, Chilterns National Landscape
15 June 2024