Where Does Cornwall’s Water Really Come From? South West Water Is Planning For The Future

South West Water, the sole provider of drinking water across the region, has revealed its strategies to secure future water resources while protecting the environment. David Harris, Managing Director for Water Services, has explained how the company sources and manages water, as well as the plans to meet growing demand and face climate challenges.

Sourcing Water from Rivers, Reservoirs, and Groundwater

Many believe that most water comes from reservoirs, but South West Water primarily sources its water from rivers. The company manages 23 reservoirs across the region, but the majority of the 490 million litres of water supplied daily comes from approximately 4,435 miles of rivers in Devon and Cornwall—roughly the distance between London and Miami. The water is transported to 37 treatment works, where it is processed to meet high safety standards before being distributed through 25,000 kilometres of drinking water pipes.

Some water is supported by releasing supplies from reservoirs upstream to maintain river levels. Additionally, groundwater, which is stored within rocks as springs and boreholes, is treated in areas where available. Like rivers and reservoirs, groundwater supplies depend on rainfall to replenish them.

Meeting the Needs of the Isles of Scilly

On the Isles of Scilly, where population surges during the dry summer months, South West Water uses a combination of groundwater boreholes and desalination. Desalination, which removes salt from seawater, plays a vital role in providing enough water to meet the growing seasonal demand.

Expanding Water Resources to Combat Drought

South West Water has been taking significant steps to ensure long-term water security across the region. Disused quarries in Cornwall have been repurposed as new sources of raw water, and desalination has been introduced as a climate-independent water supply. In 2023, a new river abstraction was constructed in Devon to pump water to Roadford Reservoir, bolstering supplies during drought conditions.

The company set ambitious targets to increase water availability in Cornwall by 45% and in Devon by 30% by 2025. Devon has already met its target, while Cornwall has boosted its water supply by 35% so far.

In addition to increasing supply, the company has been reducing demand by fixing leaks and supporting both customers and visitors in reducing water usage.

Planning for a Growing Population and Climate Change

Looking ahead, South West Water recognises the need to prepare for future challenges brought on by climate change and population growth. By 2050, the region could see up to 300,000 more residents, resulting in a demand for an extra 30 million litres of drinking water each day.

To address these challenges, the company has developed a 25-year Water Resources Management Plan. This plan outlines how South West Water will ensure a secure and sufficient water supply while also protecting the environment and local wildlife.