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Good practice

Upstream Thinking — South West Water Catchment Management Programme (UK)

United Kingdom · Exeter · See the United Kingdom profile

Since 2010, South West Water has paid 2,000+ Devon and Cornwall farmers to cut diffuse pollution across 144,120 ha, investing over £20m because preventing runoff is cheaper than treating it — independently monitored by the University of Exeter and now expanding to Bristol Water.

144,120 ha
Farmland engaged (2015-2025)
2,000+ farms
Farms engaged (2015-2025)
390,000+ trees
Trees planted along watercourses (2015-2025)
20+ £ million
South West Water investment (2010-2020 (first decade))
>50 %
Nitrogen use reduction (Otter catchment trial) (trial period)
20 %
Farmer cost saving (Otter catchment trial) (trial period)
4.8 tonnes
Obsolete pesticides safely removed (2016-2019)
Upstream Thinking — South West Water Catchment Management Programme (UK)

Details

Maturity
Scaling
Promoter
South West Water, with Westcountry Rivers Trust, Devon Wildlife Trust & Cornwall Wildlife Trust
Period
2010-present
Keywords
water utility, catchment management, agri-environment, drinking water protection, avoided-cost PES

Context

South West Water launched Upstream Thinking in 2010 as one of the UK's first water-company schemes to pay upstream land managers to protect the raw water it later treats, working with the Westcountry Rivers Trust, Devon Wildlife Trust and Cornwall Wildlife Trust across Devon and Cornwall. The programme rests on an avoided-cost logic: helping farmers cut diffuse pollution and soil erosion at source is cheaper than building extra filtration capacity to treat polluted river water.

Objectives

To reduce diffuse agricultural pollution and soil erosion at source in order to protect drinking-water quality and avoid the cost of additional water treatment infrastructure.

Activities

Farm advisors work one-to-one with landowners next to rivers and reservoirs on soil testing, nutrient management planning, manure and slurry storage, farm-track improvements and riparian tree planting. The programme also ran a fertiliser trial in the Otter catchment and a 2016-2019 pesticide amnesty to remove obsolete farm chemicals.

Results

Between 2015 and 2025 the programme worked across 144,120 hectares of farmland, engaged more than 2,000 farms, and planted over 390,000 trees along watercourses. South West Water invested more than £20 million of its own funds over the programme's first decade, with matched grant funding roughly tripling the total catchment spend. The Otter catchment fertiliser trial cut nitrogen use by more than half while delivering a 20% cost saving for participating farmers, and the 2016-2019 pesticide amnesty safely removed 4.8 tonnes of obsolete chemicals.

Conclusions

Outcomes have been independently monitored since the scheme began by the University of Exeter's Centre for Resilience in Environment, Water and Waste (CREWW). On the strength of this evidence, South West Water is running a third phase (2025-2030) that for the first time also covers Bristol Water's supply area, though isolating the programme's specific water-quality contribution from other catchment changes remains methodologically difficult.

Implementation
Indicative cost
High (€500k–€5M) — South West Water invested more than £20 million of its own funds over the programme's first decade (2010-2020), with matched grant funding roughly tripling total catchment spend; a third phase (2025-2030) extends funding to a new Bristol Water supply area.
Time to results
Long (> 3 years) — Running continuously since 2010 across three phases, with the current phase extending to 2030 — a 20-year and counting programme.
Staffing & skills
Dedicated farm advisors working one-to-one with landowners, Delivery partners: Westcountry Rivers Trust, Devon Wildlife Trust, Cornwall Wildlife Trust

Conditions for success

  • Avoided-cost logic aligning the water utility's and farmers' economic incentives
  • Long-term, multi-decade funding commitment (2010-2030 across three phases)
  • Delivery through trusted third-sector catchment partners rather than the utility alone
  • Independent, ongoing monitoring by University of Exeter CREWW

Common failure modes

  • Programme is funded through Ofwat-regulated water charges, so continuation depends on continued regulatory approval of that spending
  • Isolating the programme's specific water-quality contribution from other catchment changes (weather, wider farm policy) is methodologically difficult
  • Much of the published evidence is programme-reported rather than peer-reviewed

Where it fits

Governance type
Private regulated utility (Ofwat-regulated) delivering via third-sector partners
Scale
Regional, multi-county catchment
Income level
High-income (UK)

Data sources

Where this practice's information was retrieved from, and when.

Attachments

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