Cereals 2019: How farmers are working to keep nitrate out of the UK’s drinking water

Several water companies across the UK have been working collaboratively with farmers to keep nitrate out of drinking water.

Presenting at the Cereals Event on behalf of the water sector, Tim Stephens, from Wessex Water explained why the industry seeking to work with farmers to deliver catchment management programmes.

“Nitrate from fertilisers and manures can be found in some groundwater sources and rivers at concentrations above the 50mg/L NO3 drinking water standard,” he said.

When a key public water supply suffers high and rising nitrate concentrations, we have to make some difficult decisions.

“For example, we might have to abandon that water source, or we might have to spend millions of pounds to build and operate energy-intensive removal plants, or, we can try to tackle the problem at the source and work with farmers to improve nitrogen use efficiency.”

Working with farmers

Stephens explained that many water companies have chosen to tackle the problem at source, adding that this was seen as the sustainable option.

“The installation cost of a nitrate removal plant at a groundwater source can be around £8 million, and £250,000 to run annually,” he said.

He explained how catchment advisors work with farmers to reduce nitrate losses through education, advice and incentivising good management.

As a first step, we work with farmers to help raise awareness of the issue. We then provide advice on practices that will help reduce nitrate losses to water.

“And finally, where alternative funding isn’t available, or where farmers incur prohibitive costs by changing farming practices, we’re increasingly offering financial support.,” he said.

John Martin, an arable farmer from Dorset, is located in the Wessex Water region and has been working with Stephens since 2015 to reduce nitrate leaching into the groundwater of the Milborne St. Andrew borehole.

Martin was identified as a key farmer as his fields run almost all the way to the borehole.

Since he started working with the company, he has introduced three key steps to reduce nitrate leaching. These include:

  • Reducing post-harvest Soil Mineral Nitrogen (SMN);
  • Maximising over-winter green cover; and
  • Building organic matter.

“I use liquid fertiliser in an effort to reduce costs. It also offers flexibility in terms of application, which means I can apply when the crop needs it,” Martin said.

A grant from Wessex Water helped me to fit auto-boom shut-off to my sprayer which eliminates overlap on the headlands.

“Since ceasing dairy production in 2000, and focusing on arable production, I’ve been committed to returning more tonnes of dry matter to the soil than I remove at harvest.

“I do this by chopping every bit of straw that comes out the back of the combine, and by harvesting sunshine by growing cover crops before spring crops are drilled.

“In 2017, I entered a Mid-Tier Countryside Stewardship Scheme which helps to fund most of the cover crops I grow.

“However, Wessex Water has helped fund any extra fields and it has also provided me with a grant towards a seeder unit which sits on the top of our cultivator, allowing me to establish cover crops quickly and cost-effectively in one pass.”