Heatwave multiplies toxic blue-green algae woes on Lake Windermere

Concerns have been mounting over the presence of bacteria caused by pollution in England’s largest lake, with recent record temperatures adding to the problem.

Toxic blue-green algae is multiplying on the surface of Lake Windermere as a result of this summer’s heatwaves, increasing fears over ecological stability in the area. 

The species of algae develops in polluted water, and campaigners have long demanded action is taken to clean up England’s largest lake. Phosphate, which provides the necessary nutrients for algal blooms to grow, makes its way into Windermere from nearby United Utilities-owned waste treatment sites, the septic tanks of local homes and holiday cottages, and field run-off from farmland. 

Adding to the problem, high temperatures increase the speed of algae growth, with recent weeks bringing on a more widespread covering. The algae is potentially deadly to dogs and other animals, with several pets already succumbing to poisoning this summer after drinking the water. It can also pose a risk to human health, especially if consumed. Additionally, reductions in the level of sunlight hitting the lake, and a drop in its oxygen levels, puts the lives of fish and other species in danger. 

A petition demanding steps are taken to deal with the situation and come up with a long-term solution has now passed 100,000 signatures, enough to guarantee debate in the House of Commons. Other water systems, including Regent’s Canal, London, Middlewood Locks and Sale Water Park, Greater Manchester, Priory Country Park, Bedford, and Jubilee River, Berkshire, have also seen large coatings of blue-green algae in the past month. 

In 2019, the Environment Agency issued a damning report on the poor performance of high polluting water companies in the UK. Read our in-depth feature from December last year on the fight to save British waterways from sewage. 

Image credit: Jacqueline O’Gara