National Id
Site name
The Exmoor Mires project is part of a wider Upstream Thinking programme initiated by the local water company South West Water (SWW) to use land management to tackle problems of water quality and quantity across South-west England. The benefit to SWW is in potentially reducing the costs of water treatment. Demonstration of success will allow SWW to approach the regulator (OFWAT) for permission to develop PES schemes to deliver these benefits in future. The Exmoor Mires project involves peatland restoration through blocking historic drainage ditches with a target of restoring 2000 ha by 2015. The primary benefits of the project have been to reduce runoff (32%) and increase water storage (additional 364 m3/ha). The success of the project has been aided by the land ownership and public engagement by the Exmoor National Park Authority and support from other public agencies and research from universities.
Light or indepth?
Dorset and Somerset
RBD code
Data provider
Alistair McVittie, SRUC
NWRM(s) implemented in the case study
Climate zone
cool temperate moist
Mean rainfall
Mean rainfall unit
Mean runoff
Mean runoff unit
450 - 600 mm
Average runoff coefficient
Case Study Info
Monitoring impacts effects
Monitoring location
Catchment outlet
Monitoring parameters
Discharge, water table, DOC, colour, pH
Performance impact estimation method
Catchment outlet
Performance impact estimation information
Water qunatity:
In-situ depth to water table measurements at >200 locations across 8 †œexperimental pools† and within 3 headwater catchments.
Discharge quantified for 7 drainage features and at 3 catchment outlets.
Meteorological variables are recorded at each catchment.
Water quality:
Storm-flow sampling using ISCO pump sampler
DOC measurements (UV spectrophotometer)
Colour: UV - vis Spectrometer (Abs 400nm; Fulvic/Humic ratio (E4/E6))
Application scale
Field Scale
Area (ha)
Area subject to Land use change or Management/Practice change (ha)
Favourable preconditions
The project has involvement from a number of key stakeholder groups including South West Water (as part of its Upstream Thinking Programme), academic researchers, land owners (Exmoor National Park Authority). There has also been a history of re-wetting projects in the the surrounding area.
Design contractual arrangement
Arrangement type Responsibility Role Comments Name
Contractual agreement
Memorandum of agreement concerning the Exmoor Mires Project
Design consultation activity
Activity stage Key issues Name Comments
Implementation phase
Project website
Implementation phase
Online, classroom and outdoor educational materials and activities
Implementation phase
Outdoor events and activities
Implementation phase
Volunteering opportunities
Design land use change
Land use change type
Design authority
Authority type Role Responsibility Name Comments
Regional / sub-national water authority
South West Water
SWW is a private sector water company covering the South West of England. Its role has been to finance the project.
Exmoor National Park Authority
ENPA is a land owner within the National Park including project sites. ENPA is responsible for delivery of the project with funding from SWW
Natural England
NE is the national agency responsible for agri-environment funding and advice. Their role in this project is to fund captial works through agri-environment scheme measures
English Heritage
EH will provide advice on matters relating to the historic environment and provide project steering
Environment Agency
The EA will provide hydrological data and analysis and has a role project steering
University of Exeter
UoE is providing research and monitoring of hydrological and GHG impacts together with UoB and EA
University of Bristol
UoB is providing research and monitoring of hydrological and GHG impacts together with UoE and EA
Key lessons
This is an ongoing project of moorland rewetting involving blocking of existing drainage ditches, as such monitoring of impacts on water quality, water flow, habitats and greenhouse gases has not been completed. However, preliminary results for water quality and quantity are encouraging with storm water run-off reduced by 32% and the average depth to the water table level reduced. The project is a continuation of an exiting partnership between the regional water company (South West Water), the Exmoor National Park Authority (also the landowner) and national agencies (Natural England, Environment Agency, English Heritage). There is also academic input (Universities of Exeter and Bristol) into monitoring of inputs.
Financing mechanism
Financing mechanism information
The measures are currently funded through agri-environment payments for moorland management. If benefits can be demonstrated the hope is to get regulatory approval to develop PES schemes with payments coming from water companies. The UK Peatland Code is also in development, this focuses on GHG impacts but water co-benefits may be important in developing the PES market.
Financing difficulties
Financing difficulties information
If agri-environment scheme funding was not available SWW would have paid for implementation
Success factor(s)
Success factor type Success factor role Comments
Successful coordination between authorities
main factor

The Exmoor Mires project follows on from previous rewetting of 313ha of moorland on Exmoor by a partnership of the same stakeholders between 2006 and 2010 - 'Exmoor Mire Restoration Project'

Financing type Comments
EU-funds: Rural development funds
The capital costs of the measures themselves are funded through agri-environment payments.
Private funds
Project management is funded by SWW
Barrier type Barrier role Comments
Legal obligations / restrictions
main barrier
SWW is subject to regulatory constraint (OFWAT) regarding investments such as NWRM. The benefits need to be demonstrated to secure regulatory authorisation to continue restoration work and develop PES schemes
Driver type Driver role Comments
Organisation committed to it
main driver
Financing share
Financing share type Share Comments
Policy description
Digging of drainage ditches over decades has resulted in drying out of blanket peat bog, re-wetting is being undertaken through blocking drains to increae retention of water and carbon
Policy target
Target purpose
Runoff control
Increase Water Storage
Pollutants Removal
Oher Societal Benefits
Policy pressure
Pressure directive Relevant pressure
Policy area
Policy area type Policy area focus Name Comments
Policy impact
Impact directive Relevant impact
Policy wider plan
Wider plan type Wider plan focus Name Comments
Upstream Thinking
Upstream Thinking is an initiative run by South West Water in South West England that aims to improve water quality and quanitity through improved land management in upper catchments. The benefit to SWW is in potentially reducing the costs of water treatment. Demonstration of success will allow SWW to approach the regulator (OFWAT) for permission to develop PES schemes to deliver these benefits in future.
Policy requirement directive
Requirement directive Specification
Direct benefits information
South West Water report that reduced silt level in water could reduce treatment costs for drinking water by 20%.
Research is ongoing with respect to agricultural impacts. These include sward quality for grazing (potential for higher and more uniform water table to improve dry matter and digestability, metabolisable energy and crude protein levels) and levels of parasites (reduction in tick numbers at one restored site; reduced habitat suitability for the snail host of liver fluke). Impacts of re-wetting on cattle movements are to be studied
Costs investment information
The land is under Higher Level Stewardship scheme and would be eligible for measures including "Maintenance of Moorland†Ÿ (HL9) or "Restoration of Moorland†Ÿ (HL10) at £40/ha (€47.2/ha at £1 = €1.18) plus a £10/ha (€11.8/ha) supplement for "Moorland re-wetting†Ÿ (HL13). This would either be paid under the HLS agreement or by the project (i.e. no cost to the land owner)
Costs land acquisition information
Land is owned by the Exmoor National Park and tenanted for farming
Costs total
Costs total information
This is the total funding commitment (£2.2m at £1 = €1.18) by South West Water for the Exmoor Mires project between 2010 and 2015. This is part of the wider £9.1m Upstream Thinking programme in South West England. The Exmoor Mires project has a target of 2000ha of moorland restoration by 2015. The value relates to total project costs, not the installation of costs of the NWRM
Ecosystem impact climate regulation
Impact on GHGs (net emissions and storage) including soil carbon
Increased water storage
Increased water storage unit
Information on increased water storage
Based on 260000 cubic meters of additional water storage in peat over a restored area of 714 ha
Peak flow rate reduction
Peak flow rate reduction unit
Information on Peak flow rate reduction
Storm flow production is reduced to approximately 32% of its pre-restoration level, following catchment restoration
Maintenance baseflow
Information on Maintenance baseflow
Base flow volumes vary between approximately 201% and 48% of pre restoration levels
Reduced depth to groundwater level
Information on Reduced depth to groundwater level
Average decrease in depth to groundwater (during non rainfall-runoff event periods) with a range of 0.0103 to 0.0265 m
Ecosystem erosion control
Information on Water quality overall improvements
No significant effect of restoration on DOC and colour concentrations. The observed decrease in storm flow at the scale of the catchment would result in lower DOC fluxes
Soil quality overall soil improvements
N/A info