The water quality question: how to reduce pollution?

It may not be the first item to spring to mind when you think about the ways that life changed in the pandemic, but one of the side effects of Covid-induced lockdowns was a surge in interest in wild swimming. With leisure centres and gyms closed, people turned to the great outdoors to get their watery fix. Indeed, Outdoor Swimmer’s February 2021 Trend Report estimated that outdoor swimming in the UK increased between 1.5 and 3 times since 2019. But they also found that 60% of swimmers are worried about pollution and the risk of getting ill.

According to data from the European Environment Agency in 2019, the UK ranked 25th out of 30 European countries for bathing water quality. The latest data available from the Environment Agency classifies just four water bodies in England as having high ecological status, and none are classified as good chemical status. Data from Wales paints a similarly bleak picture.

Of course, it’s not just recreational swimmers that poor water quality negatively impacts. Actions which reduce water pollution have co-benefits for biodiversity and climate change and can increase resilience to flood and drought. Good water quality is key to biodiversity, and the many ecosystem benefits that come with it.

The Government has an objective within its 25 Year Environment Plan to achieve clean and plentiful water. In our Vision for Water Strategy, the CLA called on all sectors to do their part to improve the water environment, and supported the call to end sewage pollution. Raw sewage was discharged into rivers in England over 400,000 times in 2020 and, after much uproar, the incoming Environment Bill will now take on an amendment requiring water companies to progressively reduce the amount of sewage they discharge into waterways. Legislating this requirement is a positive step towards improving water quality in the UK.

Unfortunately, it’s not just sewage from storm overflows negatively affecting the water environment. Agriculture also plays an important role, due to the nitrates and phosphates found in the chemical fertilisers and manures spread on the land to grow successful crops.

Adding nutrients to the soil results in water pollution in a number of ways. Excess phosphates and nitrates permeate through the soil and leach into waterways, heavy rainfall results in contaminated surface water runoff, and nutrients can be lost to the air in the form of ammonia and nitrogen oxides, which are then deposited from the atmosphere into surface waters.

It’s a complex issue, and there is no silver bullet, but there are a number of practices which land managers can adopt to mitigate this issue, and better steward the water environment.

Use nutrient management techniques – carefully planning fertilizer application to reduce the quantities necessary is great way to directly tackle the source of the pollution and minimize run off.

Try organic farming – Organic farming practices have clear rules on the use of artificial fertilizers and antibiotics, with the aim of fixing nitrogen in the soil, and preventing pollution.

Create SuDS – Sustainable Drainage Systems (SuDS) can filter and hold surface water runoff, preventing the onward transmission of soils and nutrients into the wider water system. SuDS such as balancing ponds and filtration trenches have the added benefit of helping to prevent flooding by slowing the flow.

Plant buffer strips – similar to SuDS, buffer strips of trees, shrubs and grasses along the edge of fields provides additional vegetation to absorb and filter nutrients, preventing their transmission into the water system. This kind of planting, in particular on fields which border waterways, provides multiple benefits. As well as reducing pollution, it helps to stabilize the banks and boost biodiversity – riparian corridors are valuable ecosystems providing important habitats and connectivity for an abundance of species.

Start cover cropping – Among wider benefits, planting a cover crop (or allowing native weeds to thrive!) can prevent nutrient runoff and protect the soil from water and wind erosion, thereby minimizing the pollution to nearby watercourses.