Urban Canals Cool Cities by 2°C During Heatwaves

Living near a canal just became even more valuable. New research from the University of Manchester reveals that urban canals naturally cool their surroundings during hot weather, offering relief to the 6.2 million people who live within a 15-minute walk of these historic waterways.

Researchers studied 68 canals across Great Britain and Ireland throughout 2022, which featured the UK's highest ever recorded temperature of 40.3°C. They found that canals cool areas 20 to 50 meters from their banks by 1.2°C to 1.4°C in spring and early summer, with cooling effects jumping above 2°C during heatwaves.

This cooling happens right when people need it most. During the May and June 2026 heatwaves, extreme heat contributed to more than 2,700 excess deaths in England and Wales.

The canals warm their surroundings slightly at night by about 0.2°C, but this small effect is far outweighed by the daytime cooling benefits. Even these modest temperature drops make a real difference for vulnerable groups during dangerous heat.

The Ripple Effect

The cooling power of canals delivers more than just comfort. The Canal and River Trust estimates these temperature reductions save £14.4 million per year through improved worker productivity alone.

The benefits multiply from there. People who walk or cycle along canal paths to work reduce carbon emissions. Lower temperatures mean less demand for air conditioning. Better access to blue spaces improves physical and mental health for the millions who visit canals.

About 791 million visits to UK canals happened between April 2024 and March 2025. Each of those visits brought people closer to natural cooling that works without electricity or infrastructure changes.

The research comes at a critical time. Around 92% of existing homes in Britain would overheat under a 2°C global warming level by 2050. Most British and Irish buildings were designed for a climate that no longer exists.

While parks and green spaces cool cities by roughly 1°C, blue spaces like canals have received less attention in climate adaptation plans. This research proves they deserve a central role in making cities more liveable as temperatures rise.

The canals built during the Industrial Revolution are now serving a new purpose: helping communities survive the warming world that same industrialization helped create.