Catchment management | Wessex Water

What is catchment management?

Catchment management is an environmentally friendly method of influencing raw water quality at its source. It involves partnering with local stakeholders and authorities, regulators, and farmers in the catchment areas of public water supply boreholes and reservoirs.

The methods we use include sharing data, providing expertise and advice, and offering practical and financial help where applicable.

Catchment management prevents pollutants and impurities from entering our water supply as an alternative for constructing large treatment works. As a result of this work, we've not had to install treatment at any of the sites where we engage in catchment management.

Measures include covering crops to prevent winter leaching, buffer strips to reduce runoff, switching to less polluting chemicals, and improvements to farmyard infrastructure.

75%

of the water we supply comes from groundwater sources

1,500

soil samples are taken from catchment sites annually

9,000

water samples are taken across all of our catchments every year

Why is there a need for catchment management?

The water we supply has to meet drinking water standards which state specific limits on a number of pollutants including nitrates and pesticides.

While rain falling on the catchments is clean, the quality of the water abstracted from our sources is influenced by land practices in the catchment, such as the use of nutrients and pesticides. These chemicals are mostly, but not always, derived from agriculture.

The traditional way of dealing with these impurities is to build treatment works but these are expensive to construct and operate and do not benefit either the environment or customers.

The benefits of catchment management

Since 2005, we have chosen to use catchment management over building large treatment works because it:

is more cost-effective and sustainable
offers wider environmental benefits
involves working with local communities.

Some chemicals are also extremely difficult to remove through treatment, so catchment management helps to prevent them from being used in the first place.

What support is on offer for local farmers?

We offer funding to farmers in certain catchments if they can help to prevent specific impurities such as phosphorus from entering our water supply. This funding is available through a number of schemes.