Holnicote Project

Project summary

This project set out to demonstrate that by looking at whole catchments and strategically targeting shifts in rural land management practices, sustainable support to flood management may be achieved. 

Project setting

The National Trust’s Holnicote Estate is next to the uplands of Exmoor and comprises around 40km2 of land that drains the catchments of the Aller and Horner Water from Exmoor northwards through woodland, grassland and arable areas towards Porlock Bay. The project is working in a 5,042 hectare river catchment based around the estate. These catchments are typical of approximately 30% of the area of England and Wales, so the lessons learned may be transferable to similar sites elsewhere.

How is the ecosystem approach reflected in the work?

Rural land management change and intervention provides the opportunity to enhance the provision of a range of other ecosystem services within catchments.  These include landscape quality, biodiversity, carbon stewardship, water quality, amenity and recreation.

Outputs and outcomes

The project is undertaking land management measures in four key areas: the upland areas at the headwaters, steep transitional valleys feeding down from the upland areas; the lowland meadows; and the associated agricultural landscapes. These measures aim at holding rainfall runoff in the landscape at strategic sites so that it is released more naturally into the river systems. In 2014, the Environment Agency published a report that evaluated how interventions designed to improve water quality (such as the blocking of ditches in upland areas) had achieved their objetive.

Project lead and partners

The project lead is the National Trust. Partners are the Environment Agency, Penny Anderson Associates and JBA/Maslen, the University of Exeter (water quality research), Cranfield University (initial ecosystems research), Wessex Water, Somerset County Council, Exmoor National Park Authority and Natural England.


In the first phase of the project to March 2011, Defra supplied £473,000. The National Trust supplied £50,000 of funding with £104,000 support in kind, and the Environment Agency supplied £170,000 with £30,000 support in kind.

What next?

The principal objectives of the Holnicote project, which is currently scheduled to run until 2015, are to:

  • Establish a robust hydrological monitoring programme across the study area
  • Identify potential catchment (hillslope and floodplain) interventions that may contribute to managing flood risk
  • Demonstrate the practical implementation of catchment interventions (such as changes to land use, land management practices, and hydrological connectivity)
  • Assemble evidence, both from recorded datasets and hydrological/hydraulic modelling, about the impact of the catchment interventions on runoff and flood dynamics
  • Assess what the evidence reveals about the potential or actual benefits, in terms of flood risk management and the delivery of a range of other ecosystem services

The Holnicote estate is also the site of a Defra-sponsored payments for ecosystem services pilot project

Further information

For more information, see the Catchment Change Management Hub website, read a position paper on the project, or contact Nigel Hester at the National Trust.