Utility Week

34 | FEBRUARY 2021 | UTILITY WEEK Operational Excellence Analysis A problem prevented is a problem solved For more than 15 years United Utilities has been engaged in catchment management initiatives to try and stop polutants leaking into the water supply. Ruth Williams looks at its work managing groundwater catchments. U nited Utilities' (UU) supply area stretches across the North West from Cumbria down to Cheshire, incorporating flood-prone pastureland and river basins as well as swathes of agricultural land. The company is something of a pioneer in catchment management and has worked with landowners for years to prevent pollut- ants entering waterways instead of having to treat and remove them. In the northerly part of its region, UU owns around 57,000 hectares of land – pri- marily uplands surrounding reservoirs, but in the south it owns little and the landscape is more lowland, so the approach to ground- water catchment management must vary. Vee Moore, catchment management advi- sor with the company, tells Utility Week: "Since 2005 we have very much been a pio- neer in sustainable catchment management with things like woodland management and watercourse protection, and now through the work of safeguard zones the company is expanding its approach into non-owned areas in the south." She says the approach is driven by drink- ing water safeguard zones – which are determined by the Environment Agency in abstraction areas with pollution risks. Raw water quality has deteriorated and become harder to treat because of activities on land, so the company is targeting its activities in safeguard zones to improve water quality around reservoirs, groundwater and rivers. The surface water safeguard zones are designated to address problems with discol- ouration – caused by peat, algae eutrophi- cation algal blooms, and pesticides run-off. For groundwater, problems include nitrates, pathogens, and solvents. The company relies heavily on land- owner engagement and Moore says they are increasingly on board with embracing cover crops. "When we started in 2018 we had a 9 tonne nitrogen reduction target, now it's 15 tonnes, which shows how willing farmers are to adopt the schemes." She explains it's about "finding the sweet spot" between what the company needs to achieve and what farmers want to do, which has meant adapting to find best solutions both economically and ecologically. While we usually think of catchment areas as adjacent to rivers, Moore says eve- rything that drains and filtrates into aquifers has its own catchment – and challenges. "A lot of the issues we have are from diffuse pollution – lots of small pollution sources that on their own would have a neg- ligible effect, but together have a significant one." These include fertilisers, pesticides, industrial waste, waste from mining opera- tions, nitrates from stables, caravan parks and septic tanks where the catchment is not connected to mains sewerage. "Every catchment is very different, so we developed different tools, schemes and advice, there's no one-size fits all," Moore says, adding that specific risks need to be assessed in each area. In the past water companies would rely on water treatment but the holistic approach at catchment level aims to prevent pollutants at source. "We capture potential risks from land use types and assess these risks to ensure how effective our water treatment is. The whole purpose is about addressing challenges at catchment scale out in the landscape rather than relying solely on water treatment." Preventing pollutants from entering the waterways makes economic and eco- logical sense, says Moore, but she explains that quantifying the cost benefits is tricky because each area is so varied. Moore outlines some of the solutions identified across the company's southern region: Cover crops The company works with landowners and offers incentives to farmers to grow cover

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