Shapwick and Sturminster Marshall Nitrate Reduction

We are working with farmers to reduce nitrate leaching and improve water quality.

Project background

The nitrate levels in the Shapwick and Sturminster Marshall catchment remain high and are close to exceeding the Drinking Water Standard of 11.3 milligrams of nitrate per litre (mgN/l). Drinking water compliance is maintained by blending water from all the boreholes across the site.

The combined site is one of our major public water supply sources. It needs to be operating at its capacity to provide resilience across our supply network.

We aim to reduce nitrate loading into groundwater to prevent the need to build a nitrate treatment plant or extend the lifespan of a treatment works.

Over the last few years, our activity in the Shapwick and Sturminster Marshall catchment has been limited. However, given the site’s importance and increasing nitrate levels, we have allocated additional funding until March 2025 to support farmers to reduce nitrate losses to meet Environment Agency (EA) targets.

Graph to Show Nitrate Levels At Shapwick
Nitrate levels at Shapwick Source
Graph to Show Nitrate Levels At Sturminster Marshall
Nitrate levels at Sturminster Marshall Source

Who is eligible for support?

The total catchment is defined by a drinking water safeguard zone (SGZ) covering 7,881 hectares, spanning from Winterborne Whitechurch and Winterborne Zelston in the south to Ashmore in the north.

For more information on where your farm falls within the catchment and what funding you are eligible for, please email

What support is available?

We aim to support as many farmers as possible within the catchment, but we have to be strategic as to where we offer our support.

Across the catchment we are offering:

  • payment to grow cover crops
  • assistance completing the nitrate leaching tool
  • nutrient management planning, slurry sampling and analysis
  • fertiliser spreader calibrations.

In high-priority areas close to the borehole, we are also offering support to infrastructure improvements (appraised on a case-by-case basis) and a suite of infield measures to reduce nitrate leaching in high-risk fields.

Additional support

The River Stour Phosphorus Reduction Scheme (RSPRS) is another one of our projects in the area.

Some of the areas that are eligible for Shapwick and Sturminster Marshall catchment project may also be eligible for this project too. There are funding options available for nitrate leaching, watercourse fencing and habitat creation.