Experts at the University of Surrey are collaborating with the World Health Organisation (WHO) to make sure communities around the world have safe drinking water.

Billions rely on what are known as small drinking water systems, which are unregulated or maintained by major utility companies, and are vulnerable to contamination and broken infrastructure.

The Guildford-based university team has devised online resources which can be used to maintain such supplies, spotting problems before they happen.

The resources, which include a template for risk assessments and guidelines for maintaining them, have already been downloaded more than 60,000 times.

The team estimates almost 40% of the global population relies on small drinking water systems.

Dr Katherine Pond, the university's associate professor in environmental engineering, said: "Surveillance is key to detecting and responding to potential issues before they become problems.

"As climate change increases the risk to supplies globally it's vital that we empower local communities and public health officials with the necessary knowledge to protect their water."

The University of Surrey is due to host the WHO meeting of Collaborating Centres on Water in 2026.

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