UK water industry regulator Ofwat has published a new discussion paper which examines whether upstream catchment management can deliver a better deal both for water customers and the environment.

Diffuse pollution is one of the biggest challenges to improving water quality in England and Wales. Diffuse pollution occurs when small amounts of pollutants – often from many different sources – are washed into a water catchment across a wide area.

 UK water companies are currently using a variety of approaches to prevent or reduce the amount of diffuse or other pollution entering water catchments. Early results from several of the companies suggest that some of their catchment management schemes are beginning to deliver benefits for customers.

However, across England and Wales there is not yet enough evidence overall to show that catchment management schemes deliver better water quality and lower treatment costs i.e. benefits that will hold down the bills that customers would otherwise have to pay.

Evidence base needed before 2014 price review

In the run up to the next price review, the regulator says the water companies must build the evidence base to show the effectiveness and benefits of particular catchment management techniques.

Ofwat’s focus report describes some of the catchment management approaches companies are trialling to prevent or reduce diffuse pollution and the issues that need addressing in order for customers to benefit from them.

On their own, the sources of this pollution can be relatively minor. But taken together, they can significantly affect  the quality of the untreated water in individual catchments – and damage the wildlife and plants they support. 

Upstream catchment management schemes could be a more sustainable way of helping to ensure good quality drinking water by tackling diffuse pollution at source before it reaches a water treatment works. They may also help the companies to find more cost-effective ways of meeting their environmental obligations.

In the past, the companies and their customers have paid for intensive treatment processes to deliver good quality drinking water once water has been taken from the environment. Once this water has been used, it must likewise be treated to remove pollutants before it is returned to the environment, which customers again have to pay for.

Ofwat says that continuing to use such approaches would be very costly and could also damage the environment. However, Ofwat said much work still needed to be done by the companies and other stakeholders before the review in 2014 when decisions must be taken on which new schemes customers will fund – and which existing schemes they will continue to pay for.