Working with growers on a collaborative basis to tackle nitrate and pesticide losses into drinking water supplies is the goal of UK Water Companies.
It comprises of 10 UK water companies who came together at Cereals 2019 to raise awareness of these issues. Timothy Stephens, senior catchment adviser at Wessex Water said: “Nitrate from fertilisers and manures can be found in some groundwater sources and rivers at concentrations above the 50mg/litre NO3 drinking water standard.”
This can lead to water companies having to abandon the water source or install expensive, energy intensive removal plants, says Mr Stephens. “Or we can try to tackle the problem at source and work with farmers to improve nitrogen use efficiency.”
More accurate nitrogen applications, improving soil structure and nutrient-holding capacity through use of cover crops and returning chopped straw are some of the practices farmers are being encouraged to adopt.
Dorset-based arable farmer John Martin, who grows 300ha of combinable crops, has been working with Mr Stephens since 2015 to reduce nitrate leaching into the groundwater of the Milborne St Andrew borehole.
Mr Martin said: “I use liquid fertiliser. It offers flexibility in terms of application, which means I can apply it when the crop needs it. A grant from Wessex Water helped me to fit auto-boom shut-off to my sprayer which eliminates overlap on the headlands.”
Mr Martin believes a well-balanced and structured soil will hold on to nutrients such as nitrogen and has been working to increase humus levels by 1-2 per cent since he started measuring them a few years ago. “All the straw from the combine has been chopped since 2000.”
He also grows cover crops including oats, fodder radish, linseed, phacelia, sunflower and buckwheat. “We were predominantly winter cropping. Now two-thirds of the farm is spring cropping so we are using less N anyway and it means a lot of cover crops to harvest a lot of sunshine to feed the soil.
“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 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.”