We’re delighted to share a major milestone from our Breaking Barriers programme.

This spring, Ouse & Adur Rivers Trust completed the removal of the final major barrier to fish passage on the Cockhaise Brook, replacing a deteriorating concrete culvert with a new clear-span bridge and reconnecting more than 18km of river habitat for fish and wildlife.

While this was just one project within our catchment-wide Breaking Barriers programme, it represents something truly special. Thanks to years of partnership working with landowners, the Environment Agency and Southern Water, the Cockhaise Brook is now believed to be the first sub-catchment in the Ouse and Adur river systems where all major barriers affecting fish passage on the main river have either been removed or mitigated.

This achievement has been many years in the making. Since 2019, work has included fish passage improvements at Holywell gauging weir, the removal of a large brick weir, and now the replacement of the final problematic culvert. Together, these projects have reconnected the entire river system, allowing species such as eel, brown trout and sea trout to access habitat that was previously difficult or impossible to reach.

The benefits go beyond fish passage. Alongside the bridge installation, we have reprofiled riverbanks, planted native wetland species, added spawning gravels and large woody material, and controlled invasive Himalayan balsam. These improvements will help support biodiversity, improve river resilience and restore more natural river processes.

Perhaps most excitingly, fish populations are currently the main reason the Cockhaise Brook is classified as having Poor Ecological Status under the Water Framework Directive. All other monitored elements already achieve Good or High status. By restoring connectivity throughout the catchment, we hope to support fish populations in recovering to the level needed for the brook to achieve Good Ecological Status – potentially making it the first sub-catchment in the wider Ouse and Adur catchments to reach this important milestone.

None of this would be possible without the support of our members, volunteers, landowners and funding partners.