WORK on a transformational project to return the River Ribble to its natural course lower down stream has been seized by the Ribble Catchment Partnership, thanks to exceptionally low spring water levels.

The river begins at Ribblehead, just above Horton-in-Ribblesdale and travels through North Craven before meandering west and out to sea near Preston.

In what is believed to be the widest weir removal scheme currently underway in Britain, excavators moved in this week to begin removal of a redundant 50-year-old weir near Salmesbury.

The work will increase biodiversity and ease the movement of migratory fish like salmon, smelt and eels which will make their way upstream.

The works are part of the new Ribble Life for Water Scheme supported by the Water Environment Grant administered by the Environment Agency, and funded by the

European Agricultural Fund for Rural Development.

Ribble Rivers Trust Director Jack Spees said: “We are really pleased to see this project finally underway.

“The Ribble Life for Water programme started in early 2019 and over the last year we have been planning and preparing for the works on the ground to get going.

“We responded to the outbreak of the coronavirus pandemic by delaying a significant amount of projects and work.

“However, as the situation has evolved, it was agreed that this particular project was safe to carry out under the current restrictions.

“The long spell of dry weather has offered a window of opportunity where the river is at record seasonal low, meaning the project can be carried out more safely.

“This programme will bring huge benefits, not just to the river, but all riverine wildlife and beyond.

“At a time when the economy is being severely affected by the Coronavirus, we are pleased that by adapting our working processes we can start work and support local companies.”

A programme of large-scale engineering projects will restore natural flows and improve water quality, habitat and biodiversity.

To date, planning and preparation have been the principle activities, but during the winter, work started on Pendle Hill to restore areas of degraded peat that were causing diffuse water pollution, increased downstream flood risk, emitting carbon and reducing biodiversity. The peat work has had to be paused due to the coronavirus pandemic and is hoped to be completed this coming winter.

Samlesbury Weir was constructed in the 1970s to monitor low flows on the Ribble, but its effectiveness led to it being permanently decommissioned. The weir itself causes significant problems for the river and riverine wildlife and has also been the site of several serious injuries to members of the public.

Weirs impound water and sediments, interrupting natural processes and habitat creation, which reduces the biodiversity and abundance of wildlife that would otherwise be expected.

Delaying their movement exposes all fish to predators, poaching and water quality issues, further reducing their numbers. Research has shown that all weirs – irrespective of size – have significant impacts on migratory species and this is compounded by the number of weirs in the Ribble Catchment.

Immature eels or ‘elvers’ are poor swimmers and although they may wriggle over weirs, they are often heavily predated. Eel populations in the UK are at particular risk with huge reductions in numbers.

Another species to benefit, is the ‘smelt’ or ‘Cucumber fish’ (owing to its distinctive aroma). Smelt were once so prevalent in Lancashire that they supported a significant fishing industry, but water quality and weirs have reduced their numbers to such an extent that the Ribble Estuary as far upstream as Samlesbury weir has been designated a Marine Conservation Zone to try to increase populations.

The Ribble was once one of the best salmon rivers in England, but in recent years, salmon numbers have decreased significantly, with angling catches dropping by up to two thirds since 2010.

Although adult salmon may not find the weir too much of an obstacle, smolts – juvenile salmon heading back to sea – are significantly delayed by even the smallest weir.

EA scientists also studied freshwater insects upstream and downstream of the weir and found that invertebrate numbers upstream were lower and less diverse. Weir removal should support increased insect life which will help fish, bird and bat populations.