2 days ago
- General
- Powys County Times
The Shropshire waterways being boosted by natural flood work
The second phase of a natural flood management (NFM) scheme that is being delivered in Shropshire is on target.
Called 'slow the flow', the project runs until next March and is aimed at delvering NFM schemes across seven catchments in the Corvedale: Aston-on-Clun (the unnamed tributary of the River Clun), Battlefield Brook, Clunton (the unnanmed tributary of the River Clun), Gobowen (tributaries of the River Perry), Hilton Brook, Shyte and Sytche Brooks, Much Wenlock, and the River Corve and tributaries.
During the scheme, Shropshire Wildlife Trust (SWT) has been liaising with local flood action groups and the National Flood Forum to target where its work is most needed. It comes after Shropshire Council with Telford & Wrekin Council secured over £750,000 from DEFRA's Natural Flood Management Demonstrators fund.
In order to meet the requirements, Shropshire Council worked with Cardiff University to monitor the effectiveness of NFM features to establish a method of quantifying the benefit of wood debris dams in a computer model.
The impact of Covid meant that a large number of interventions could not be delivered, so the council was unable to allocate the remaining capital. However, because SWT has previously worked in the catchment before, it is continuing the work it started in 2018.
During the first phase, over 100 landowners were engaged with and more than 350 people attended events linked to the project.
A total of 1,000 NFM interventions had been installed, including storage ponds, swales, woody debris dams, sward lifting, improving field infiltration, tree and hedgerow planting.
People were able to see some of the key work as part of the Shropshire Hills Summer Forum and Field Visits event.
Starting at Wildehope Manor, a Grade I listed building that is looked after by the National Trust in Longville in the Dale, near Church Stretton, walkers were able to see some of the leaky barriers along the Wilde Brook that reduces the amount of water in the stream during high flows.
'It's working with natural processes,' said Sarah Mackness, water resources project manager at SWT.
'The designs we have used have evolved across the length of the project.
'We are replicating a lot of the work in the Corvedale, but we've also got funding for other catchments across Shropshire
'For every £1 spent on natural flood management, after 10 years there's a £4 benefit in terms to reduced risk to communities downstream and infrastructure. After 30 years, that goes up to a £10 benefit.'
Ms Mackness also showed visitors how simple methods like placing a sill across a track can also prove effective.
'It was coming down the track, round the corner, and straight down the track,' she said.
'Heavy rain was washing soil away. Something as simple as a sill across the track is enough to cause the water to flow into the ditch at the side and flows much slower before it eventually reaches the stream at the bottom.
'How can we slow the water down, slow the infiltration and store the water upstream?'
However, Julian Radliffe, who owns the land, said it doesn't always work.
'In the roadway, they put French drains in which are effective but over the years we probably have to dig them out because they get silted out,' he said.
'Then the water comes, down this track not down the ditch. We've got to bring our small diger and clear away the vegetation.
'The attrition rate on the dams is higher here than we expected because the flow has been much heavier because of the change of the climate than we originally modelled.'
Ms Mackness added: 'It only works when you're working with landowners. Because of how the project is funded, we don't have any funding for maintenance.
'With it being a demonstrator project, especially the initial phase, we've learnt a lot from it and what we thought would happen hasn't always been the case.'
Two people who went on the trip said it was very beneficial.
'We've had heavy rainfall that's travelled across two of our fields,' said Emily Esp.
'There's been houses and garden landscaping that's changed over time. I would like to help them by slowing the flow from the fields. I can't control what goes on in their garden and what they do with their landscaping, but I can slow it before it gets there.'
Martin Steer added: 'It's nice to have engagement from the farmer as well. It's great to see all these people come together – they're all sharing knowledge.
'It is good progress being made, with soil management coming at the top of the agenda.'
