For many years, structures such as weirs and culverts have restricted fish movement into Cockhaise Brook, limiting access to vital habitats across the sub-catchment. Since 2023, we have been working to remove these barriers, and we’re delighted to now be tackling the final major obstruction—opening up 95% of the brook to all fish species.
This final stage focuses on the removal of a triple-piped culvert that currently forms a ford crossing over the river. While functional for access, the structure has significantly impeded the natural movement of fish through the watercourse.
Working closely with landowners and tenant farmers, the culvert is being carefully removed and replaced with a free-spanning bridge. This solution maintains essential access for land management, while restoring a natural, unobstructed river channel—allowing fish to move freely through the system.
Funded by the Environment Agency and Southern Water, this project represents a major milestone in addressing the 300+ barriers to fish migration across the catchment. Cockhaise Brook will become the first sub-catchment where all major barriers have been removed, setting a strong example for future restoration work.
Why this matters
We recognise that removing structures such as weirs and culverts can be a sensitive and sometimes controversial issue. Many of these features have been part of the landscape for decades, and in some cases are valued for their history, appearance, or perceived role in managing water.
However, these structures can significantly disrupt the natural function of rivers. Even relatively small barriers can prevent fish from reaching upstream habitats needed for feeding, spawning and shelter. Over time, this fragmentation can reduce fish populations and impact the wider health of the river ecosystem.
By carefully removing or modifying these barriers, we are restoring more natural river processes—improving connectivity, supporting biodiversity, and helping rivers adapt to changing environmental conditions.
Where access or land management is required, as at Cockhaise Brook, we work closely with landowners to design solutions that meet both environmental and practical needs. In this case, replacing the culvert with a bridge ensures continued access while delivering a fully open river channel.
Projects like this are an important step towards healthier, more resilient rivers that benefit wildlife, local communities, and the wider environment.
