New 15-Minute Water Test Could Save Swimmers From Getting Sick

Getting sick after a beach day could soon become much less common thanks to a breakthrough water testing device that delivers results in under 15 minutes.

Molendotech, a startup from the University of Plymouth, developed a portable test that detects E. coli and other harmful bacteria on the spot. Traditional water testing takes one to two days, meaning swimmers often enter contaminated water before anyone knows there's a problem.

The company is now launching an app in October that will map water quality across Britain and the US in real time. The app will combine data from daily water tests with rainfall and tidal patterns, using artificial intelligence to predict where water might be unsafe.

The timing couldn't be better. This year alone, 164 beachgoers reported getting sick after swimming at UK beaches, suffering from gastroenteritis, ear infections, and skin problems. Current testing methods simply can't keep up with rapidly changing water conditions.

Professor Simon Jackson, who founded the company in 2018, created the first version of the test after his stepdaughter got conjunctivitis and a throat infection requiring antibiotics from swimming in the sea. He saw families like his needing better protection.

The handheld device, called Bactiquick, works differently than traditional tests. Instead of growing bacteria cultures in a lab and counting them, it detects a molecule called endotoxin that bacteria release when they break down. The test produces a color change that converts to electrical signals and displays a numerical reading within 15 minutes.

A smartphone app shows results using a traffic light system. Green signals safe water, while amber and red warn that bacteria levels exceed UK and EU safety thresholds.

The device costs £300, with each test sample around £25. Sales have skyrocketed from a few thousand pounds monthly in mid-2024 to £94,000 in May 2025, nearly 30 times higher.

The Ripple Effect

Water companies across Britain are now testing the devices, along with local authorities and councils. The technology is expanding to North America, New Zealand, and Australia after Molendotech raised £860,000 from investors, bringing total investment to £2.4 million.

The device has already caught contamination that standard testing missed. Last July, it rated Saltdean beach in Sussex as high risk when the Environment Agency had graded it excellent. Jackson explains that infrequent testing creates dangerous gaps in protection.

The system works both ways, sometimes giving beaches the all-clear when official ratings show poor quality. This reflects how quickly water conditions change and why real-time testing matters so much.

Climate change makes this innovation even more crucial. As European and UK waters warm, new species of dangerous bacteria are appearing, including Vibrio species. Louisiana officials just warned beachgoers this week about nine cases of Vibrio vulnificus infections, a flesh-eating bacterium found in coastal waters.

For the first time, swimmers will have the power to check water safety before diving in, turning what was once a gamble into an informed decision.