Flooding: changing land-use practices

Upstream thinking

12 September 2016

Organisations in the South West of England are working together to improve water management by changing land-use practices, Lorna Devenish reports

Questions around land use and water have spread across the country in the wake of yet more devastating floods last winter.

Since the deluge receded, water treatment professionals up and down the country have worked overtime to turn the heavily silted spate into tap water that we can drink.

Floods have a wide-ranging impact on society, and not only in terms of devastating homes and communities. But could different land management practices help? In the South West of England, a group of organisations who believe that land use is critical for water management is working together for change.

South West Water, Devon Wildlife Trust, Cornwall Wildlife Trust, the Westcountry Rivers Trust and Exmoor National Park Authority came together in 2008 under the banner Upstream Thinking to develop a programme of landscape-scale changes to land use. They now work with a wider group of partners, including the Environment Agency and the University of Exeter.

The academics are a key part of the project. They have collected data that is beginning to show that significant amounts of water can be stored on the land, river flows can be slowed in winter and boosted in summer, and carbon can be locked into peat bogs instead of being lost into the atmosphere or into rivers. If soil compacting is tackled and degraded peatlands are restored, the landscape can provide a significant buffer to downstream flooding.

Advisors across 11 catchments offer support and guidance on alternative techniques to manage and farm the land, techniques which bring both economic and environmental benefits. They discuss in detail what can be done on farms to protect water quality and develop a farm water management plan. Grant funding is also available for capital works.

Putting the peat back

One part of the project is peatland restoration. On Exmoor, more than 2,000ha of peatland have been surveyed, assessed and restored where possible, using ditch blocks to stimulate the bogs’ hydrological function. Up to 500ha more are to come.

Lead researcher Prof. Richard Brazier has coordinated an award-winning research programme to quantify the benefits of the work that has been carried out. He explains: 'During wet winters, as we have recently experienced, you only need to look around the landscape to see that there is evidence of local flooding and soil erosion everywhere.'

The research team has shown how enhancing water storage on Exmoor’s peatland can improve water quality, as well as releasing less into the River Exe during flooding.

With a third less water leaving experimental sites on the moorland during peak storm flows, the initial results indicate that the work could provide benefits in terms of both water quality and quantity. Wildlife is also benefitting, with the return of rare wading birds to the restored sites.

South West Water has brokered an agreement with Exmoor National Park Authority and the National Farmers Union for a groundbreaking system that will guarantee a per-hectare payment for participating upland landowners for 10 years, in recognition of their contribution to maintaining the land in a way that enhances water quality and storage.

It has drawn heavily on the evidence of increased water storage and quality benefits from mire restoration.

Case study: slurry storage

Cornish farmer Andrew Jones from Higher Trevallett Farm near Launceston was awarded a £75,000 Upstream Thinking grant in 2013 after an assessment by the Westcountry Rivers Trust (WRT).

The money, which Andrew matched, went towards building a new covered slurry store for his dairy heifers. The tank is immediately below the barn where the cows are housed and provides five months’ storage where previously he had space for just a month’s slurry.

'It’s a big weight off my mind,' Andrew says. 'I can sleep easy at night knowing that the slurry store is not going to overflow, and I can spread the nutrients on the land at the optimum time so that it stays on the land and doesn’t run into the rivers. It means we can wait for exactly the right conditions before we spread.'

Senior Farm Advisor Ross Cherrington from the WRT says it has recorded an increase in the number of varieties of invertebrates, suggesting an improvement in water quality in the nearby River Kensey, which flows into the Tamar above South West Water’s raw water intakes at Gatherleigh and Gunnislake.

Looking further afield

The work on Exmoor demonstrates the complex economic and legal challenges that can arise if we are to manage rural land for more than simply food production and compliance with stewardship requirements.

How do the new opportunities for land-water management play out with existing commitments under the Basic Payment Scheme, a range of statutory designations and existing arrangements such as the Higher Level Stewardship of the new Countryside Stewardship schemes? And what are the economic and practical implications for existing farming practices?

The work on Exmoor has led the way: many of the lessons can apply in a much wider range of situations, and provide a basis for further work in different locations. The £12m programme for 2015–20 includes two distinct strands of work: ongoing restoration of peat bogs on Exmoor, working with owners of upland areas; and advice and grants for lowland farmers, whose land adjoins key rivers used for public drinking water supply.

RICS Rural Policy paper recommendation

  • The Environment Agency needs to adopt an Integrated Catchment Management approach in order to help mitigate flooding and, where possible, protect and enhance good agricultural land.
  • Practical work in the uplands such as tree planting and measures to slow water can complement sustainable hill farming, and has been shown to be successful in preventing downstream flooding. Such work should be given incentives through agri-environment schemes and taxation.
  • The aim should be to hold water in the landscape. The nexus of flooding, drought, aquatic fauna extinction and water quality decline is a harbinger of enhanced loss of water from the landscape, where run-off rates are left unchecked. Run-off attenuation can recharge groundwaters for abstraction, intercept overland flow flood pathways, and retain valuable suspended sediment and nutrients for enhanced farm productivity.

Charles Cowap is a rural chartered surveyor and registered valuer who has been involved with the partnership, and he has used this experience as the basis for a number of briefings for the profession, working in conjunction with RICS Rural Professional Group. RICS sees this as an increasingly important area of professional practice, given the growing complexity and challenge of rural land management.

He was commissioned by RICS to write a thought leadership paper entitled Challenges for International Professional Practice: from market value to natural value, and a second paper looking at the valuation of ecosystem services commissioned from him is due shortly. The National Trust’s experience with storm run-off management at Holnicote, Somerset, is another valuable example of what can be achieved.

Cowap says: 'Taking projects like these together it soon becomes clear that the water challenge is about far more than just pumping, dyke-clearing or tree-planting. We need to think about the full water cycle from the uplands to the sea.'

On the lowlands, grants of up to 50% are available to enable farmers to make practical changes – for instance measures such as slurry storage, riverbank fencing, buffer strip planting and pesticide management. These grants are subject to a 20-year covenant agreement.

In the headwaters of the Exe, grants and advice are available for a range of interventions including woodland creation. In addition, by participating in Upstream Thinking, farmers can often access further subsidies in recognition of their environmentally sensitive farming practices.

Prof. Brazier concludes: “It has a benefit for the water company – cleaner water and more water storage; it has a benefit for society, because it alleviates flooding downstream and reduces the need for dredging; and it has a financial benefit for the farmer, as soil is retained on the fields and the farmer is rewarded financially for looking after their soil and water.

'A landscape that stores water in the wet season and releases it more slowly in dry periods is more resilient to climatic variability and can help society to adapt to the kind of extreme weather that we have seen in recent months.'

Lorna Devenish is Communications Officer for South West Water

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