It’s amazing what you can see from space - the Amazon rainforest, the Great Barrier Reef, the Grand Canyon, the pyramids of Giza, even the River Thames. But there’s something else that satellite technology can spot from high above Earth’s atmosphere… underground water leaks.

Water leaks are costly. If you have an underground leak on your business premises, the first indication is usually a higher water bill than normal. Leaks also waste a lot of water, which is bad for the environment as, in order to deliver as much potable water to serve everyone’s needs, more water has to be extracted from the natural environment.

It’s estimated that just over three billion litres of water is being lost every day in the UK. The water regulator Ofwat has given the water sector the target of reducing leaks by 16% within five years - this alone would be enough water to serve the needs of Cardiff, Birmingham, Leeds, Bristol, Sheffield and Liverpool, leading to greater water resilience.

The problem in Cornwall

Low reservoir levels in Cornwall have left the county in a vulnerable position. It isn’t far from ‘Day Zero’ - the point at which demand outstrips supply. So the water companies need to do something drastic in order to guarantee water supplies, especially in the summer months when rainfall is at its lowest and tourism at its highest.

The satellite solution

South West Water has therefore turned to cutting-edge satellite technology to help it find and fix leaks. The satellite technology, which is the same as that used to search for water on other planets, is designed to detect leaks that are up to two metres underground. Using microwave sensors, the satellite takes a photo of a particular area every couple of weeks. Its radar sensors look for the unique signature of potable water (not wastewater) collecting under tarmac, earth, concrete or brick. It can even filter out pools of water that are supposed to be there, such as swimming pools and fountains. Results are assessed according to the probability they are a leak and sent to South West Water. Leak technicians can then investigate.

This cutting-edge technology, combined with an increase in staffing levels, has enabled the water company to find and fix more leaks than ever before - in October 2022, it reached a high of 2,500. South West Water is also fixing leaks found on customer properties for free, saving enough water to serve the equivalent of 8,000 homes.

Satellite water leak detection

Satellite water leak detection technology is being rolled out around the world to help water companies identify leaks and save our precious supplies of water. As an example, South Staffs Water, incorporating Cambridge Water, is using satellite leak detection technology to great effect. Leak detection rates have increased by a massive 700%, with a saving of over two million litres of water every day. Leaks of all sizes have been detected beneath tarmac, concrete, brick and earth.

In the future, the same technology could be adapted to look for wastewater rather than potable water, helping to discover leaks in the sewerage system.

Do you have a leak? Castle Water can help...

Castle Water provides a range of additional services including Leak Detection, Repair and Assistance. When you are ready to find your leak, simply fill out our leak detection form to book a site visit.

If you suspect a water leak on your premises, first check out our free Leak Assistance Guide. The guide provides helpful information on how to identify leaks as well as when to seek further advice.

Castle Water provides a range of services to choose from, including business water services, water efficiency audits and wastewater management. Contact us today.


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