Reducing agricultural pollution – Working together with local farmers

Matthew Pitts, Catchment Strategy Manager, Bristol Water

Our most important asset is raw water.  Good quality raw water makes it easier and cheaper for us to provide good quality drinking water to our customers.

Back in 2007, Bristol Water had the perhaps dubious accolade of being the first water company to detect metaldehyde in raw water.  This prompted the rest of the industry to start looking for it and finding it.

At Bristol Water, we decided that the best way to tackle the problem was at its source, particularly as it is very difficult to remove at treatment works without significant expense.  In this case that meant talking to the farmers and growers across the catchments where our water comes from.  We were able to explain why metaldehye is a problem and how and when it is most likely to move from the land to rivers and streams.  We collected samples from streams across the catchments, which we analysed to tell us how much metaldehyde was in the water, and under what conditions we saw the highest concentrations.  We were able to clearly show farmers which fields weather conditions were most risky.

We started this engagement work in 2010 and called it the Metaldehyde Action Project and have been running it ever since.  We have worked with farmers to reduce the use of metaldehyde, ensure that when it is used it is used with caution and according to risk assessment on the basis of individual fields and weather conditions.  We have also helped farmers to calibrate their pellet application equipment, and we have subsidised and promoted the use of non-toxic alternatives to metaldehyde such as ferric phosphate.  By doing all this, and thanks to the cooperation of farmers, we have reduced the frequency and size of metaldehyde concentrations in raw water samples.  This approach has been much cheaper than building new water treatment works to remove metaldehyde. The relationships we have built with the farmers are very important to us.  We rely on them as stewards of the environment from which our single most important resource comes – water.

In 2015, we expanded our catchment management approach to deal with nutrients in the Mendip reservoirs, as these nutrients were making the water very difficult to treat, and like with the metaldehyde problem, would ultimately require us to build new expensive treatment systems.  We formed the Mendip Lakes Partnership, bringing together a number of organisations working in the Mendip catchments with similar aims around improving the farmed environment.  This allowed us to present a coordinated and consistent approach to farmers, and a ‘one stop shop’ for advice on nutrients, soils, water and for help with applications to the Government’s Countryside Stewardship scheme.  We have also set up our own Bristol Water Catchment Grant Scheme where we have helped farms make improvements which will reduce their pollution risk.  We put on workshops and events to make sure everyone is aware of the issues we are dealing with and the support we can provide, and we provide feedback on the quality of the rivers and streams in the area.

We believe our catchment approach is working, and that it is sustainable and cost-effective.  We plan to continue the approach and to build on the relationships we have developed over the last 10 years, and to widen it across the Cheddar Reservoir catchments.  We will strive to innovate and to validate our approach.  To do this, we will build partnerships with organisations like universities and neighbour water companies.

We will continue to collect data, so we know how and if our approach is working.  We don’t know how pressures on the environment will change in the future, so it is important that we maintain and build the profile of water stewardship.  Climate change is one example of a source of change.  This could have direct effects on the reservoirs for example by increasing algal blooms, but also indirect effects such as on soil chemistry and implications for the types of farming which are viable.

Economic effects of leaving the EU are as yet unknowable – a scenario driving increased agricultural intensification is not infeasible. Our catchment approach is an example of how we are providing a resilient, sustainable and cost effective water supply for our customers.

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