The waters around the UK were once filled with seagrass but changes to water quality as well as fishing and dredging has caused the decline of as much as 92 per cent of these plants.

Affinity Water was awarded £250,000 from Ofwat’s Innovation in Water Challenge fund to restore seagrass beds off its coastline in Essex, which partner Project Seagrass believes could be as effective as sequestering carbon as woodland, but potentially faster.

Affinity, together with Anglian Water and a host of environmental groups, has launched the project to explore the feasibility of planting and restoring seagrass beds, creating a seed nursery to sustainably supply the plants and, crucially, developing a “blue carbon framework”.

Aaron Burton, head of environmental strategy at Affinity, explained the concept came about during work to develop the company’s net zero action plan and carbon reduction strategy. Meeting the sector’s commitment net zero by 2030 will require offsetting of process emissions that, presently, cannot be eliminated so this project presents an opportunity to sequester at a local level with wider community benefits.

“We will look at how successful seagrass is for sequestration,” Burton said. “Some evidence suggests it is as successful as woodlands, but potentially faster. What we need is the additional science to further prove that, then develop a framework to asses that and enable carbon credits.”

He said the framework would be an equivalent of the Woodland Carbon Code voluntary standard for woodland creation projects. If successful, carbon credits could be bought by any company wanting to offset its C02 emissions, as an additional option to tree planting.

“The idea is we want to create something for blue carbon, which doesn’t exist at the moment. At the moment if a company were to do seagrass restoration, it couldn’t claim any carbon benefits from it. In anything to do with offsetting it’s important to make sure its effective and explore the longevity of it.”

The blue carbon framework will set out how much can be sequestered through different methods, how each can be assured and how credits can be sold to organisations wanting to offset.

“From the water company perspective there are multiple benefits: carbon sequestrations and helping us get to net zero, reducing nitrates and improving water quality; there are other natural capital benefits that can come from seagrass in terms of protecting coastlines and reducing flood risk as well as improving biodiversity and supporting fish stocks.”

Project Seagrass, a charity focused on restoring seagrass, has worked on restoration schemes in Wales and Scotland with WWF and together with the water companies and project partners will scale up the seagrass sequestration.

Burton said other water companies exploring sequestration projects such as restoration of kelp forests and salt marshes will benefit from the blue carbon financing work. Oxford University will work on the blue finance framework and Environment Agency and Natural England will be involved to address regulatory barriers.

The project will take place over two years, at the end of which the team should have trialled four restoration sites and monitored the progress of how successfully seagrass grows in the area. The team will have developed a seagrass nursery that will provide seeds not only for this project but also future programmes around the country.

Burton said the stretch of coastline being assessed had as much as 380 hectares of seagrass in the 1970s that have disappeared. He explained catchment management and improvements to water quality was an enabler to restoring the plants.

The project was awarded the funding from the first round of Ofwat’s Innovation in Water Challenge. 

The £40 million Breakthrough Challenge launched this month and will run throughout AMP7 to encourage collaborative innovative solutions to common challenges faced by the industry.

More case studies from Ofwat’s innovation competition, as well as deep dives into innovation and technology, will feature in our new Utility Week Innovate hub, to be launched later this month

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