We restored the River Keekle near Whitehaven in a £1.5 million project that started in 2019 and was completed in summer 2020.

The river was lined with plastic in the 1990s. The plastic was breaking up and pieces being washed downstream, creating blockages, and localised flooding. We removed the plastic and restored the riverbed.

The issue

The River Keekle is a tributary of the Ehen located around 3 kilometres east of Whitehaven, in West Cumbria (grid ref. NY 00452 17651).

The river was heavily modified until the 1990s due to nearby coal mining. After mine spoil was buried across the site the river was lined with an HDPE plastic liner. This liner was failing and heavily degraded, posing a flood risk and potential catastrophic contamination issue for the Keekle, as well as the River Ehen which is a Site of Special Scientific Interest and a Special Area of Conservation. Research by the University of Salford showed the liner had been shedding 500kg of plastic particles per year since its installation. 

The scale of the problem

There was also concern that the river would vertically erode through the clay cap installed below the liner and expose ground water potentially mixed with mine waste that was buried in the 1990s, allowing heavy metals and chemicals to leach into the Keekle and further downstream. Whilst all of the EA’s sampling of water quality currently proved there was no contamination across the site, if nothing was done to stop erosion, there was a real possibility of the Keekle exposing mine waste in the future.

The Upper Keekle was also failing under the Water Framework Directive classification as a habitat for fish due to mining-related modifications. The modifications include the liner, bed-check weirs that washed out during floods in the 1990s, erratic boulder locations and areas where the plastic has broken up, creating barriers to natural fish migration.

What we’re doing

We removed the plastic liner, which was installed in a 2.5 kilometre stretch of the river, and restored the riverbed. The project was split into two phases.

Summer 2019: Trial site

In summer 2019 we worked with the Environment Agency to remove the liner from a 170-metre trial site between Walkmill Bridge and Keekle Bridge. Nine tonnes of plastic were removed and recycled, with some being used to make a picnic table and bench which you’ll find at the Walkmill Woodlands car park near Moresby Parks. We tested different methods of removing the plastic to find the best way to complete the full removal.

We’re already seeing massive positive changes in the restored section. There’s natural gravel, cobbles and boulders in place of the liner, plus new sediment deposition in places which is proof that the river is re-naturalising itself now the plastic isn’t in the way.

Summer 2020: Full removal

We used what we learned in phase one to remove the remaining 2.3 kilometres of plastic liner. We removed around 150 tonnes of plastic, which was recycled.

The riverbed was restored with cobbles, stone, boulders and gravel. In the much smaller phase one site we were able to use stone already on site. For phase two we brought in thousands of tonnes of extra stone to replace the plastic.

Instead of erratic erosion of the riverbanks depositing tonnes of sediment into the river system, the river is now re-naturalised and should provide fantastic habitat for fish spawning and other wildlife.

This flyover from partway through phase two shows the scale of the project:

Expected benefits

Removing the failed plastic liner will reduce plastic pollution and localised flooding downstream.

The river is now in a much more natural condition, improving the habitats for salmon, trout and other fish species. We directly improved 2.5 kilometres of river and opened up access for fish to the further 4 kilometres of river upstream as they were prevented from migrating by the plastic debris.

The project also removed a threat to highly endangered freshwater mussels further downstream in the River Ehen. As the liner repeatedly failed, excess sediment was released into the Keekle which made its way into the Ehen, posing a significant risk to the mussels.

Before and after 

 

  

 

Funders and partners

This is a major project which could not have happened without the generous support of our funders.

The project is part of the Environment Agency’s River Restoration Programme in Cumbria – one of the biggest portfolios of river restoration projects in the UK.

Phase 1 was funded by the Environment Agency’s River Restoration Programme. Phase 2 was funded by the European Agricultural Fund for Rural Development’s Water Environment Grant.

Dumfries-based recycling company Plaswood from Berry BPI provided generous support and covered some of the costs of recycling the plastic.