In News |

May 6, 2024

Challenging Lake Windermere’s water quality

Map Impact the pioneering environmental data services company has published its findings from the UK Space Agency Climate Call backed project, which studied the factors impacting the freshwater quality in Lake Windermere using satellite technology.

The strongest impacts on the Lake’s water quality came from increased levels of human movement in the catchment area creating over capacity issues for local wastewater infrastructure, and higher temperatures from weather and climate conditions. Both lead to increased chlorophyll and algal bloom events that significantly harm the Lake’s ecosystem. Agricultural activity and land use were not found to be a major contributor to spikes in algae within the Lake.

The project commenced in September 2023 and ran for six months, drawing on knowledge from local community stakeholder groups, and historic data as well as records from various organisations. Satellite imagery and derived data, covering the entire Lake Windermere catchment area, were analysed to provide fresh insight on the algal blooms, caused by increased nutrient input, and regularly seen in the Lake during the peak tourist season.

Richard Flemmings, Map Impact CEO, commented “By taking a novel catchment wide perspective we have been able to bring new evidence to support increased understanding of Lake Windermere’s condition. We’re proud to be able to openly publish the results of this study, including limitations, for use by anyone in the community.”

Dr Paul Bate, Chief Executive of the UK Space Agency, said: “The UK has a long history of expertise and innovation in Earth observation, developing satellites to collect increasingly detailed data and using that information to build services that help protect our planet.”

“Map Impact’s report, focusing on one of the UK’s most iconic and important lakes, demonstrates how these data can be used to give us clearer information about how the natural resources around us are changing, helping communities and decision-makers take tangible steps towards improving pollution levels and mitigating their impacts.”

Local campaign group Save Windermere has maintained a view that the inadequate local wastewater infrastructure was causing excessive nutrient input to the Lake and its spokesperson Matt Staniek commented on the findings “This isn’t just about visitor numbers or climate change; it’s about the failure of the Environment Agency and United Utilities to adequately manage and invest sufficiently in sewage infrastructure, essential for the lake’s resilience to these pressures.”

Historic bloom events were retrospectively studied using satellite images. These were correlated with other data sources; the Covid-19 lockdown periods provided an ideal control situation.  Travel restrictions limited human movement to the largely local resident population of c40,000 in the catchment area during the first period; the second period, where travel was allowed within the UK, saw some daily resident and tourist visitor figures peak at 320,000. These figures were sourced from detailed anonymised cell-phone data provided by a leading operator.

Algae growth is normally driven by a combination of climatic conditions and nutrient input, often flowing into the water from wastewater discharge and agricultural runoff. Therefore, in addition to metrological and human movement data, catchment land cover and land use was also studied within the project.

Full details of the study can be found on the following link: