Windermere from Brant Fell copyright Dave Willis

Love Windermere

Love WindermereA new Love Windermere partnership launched in July 2022. It's the biggest ever cooperation of sectors to tackle challenges in the lake. The partnership is developing a science-based plan to set out a road map for environmental protection that could be replicated across the UK.

Nutrients, climate change, more extreme weather patterns and the seasonal variations of the tourist population are all predicted to put the lake and its water quality under increasing pressure in the coming years.

Updated 4 October 2022

Projects to help study and improve Windermere's water quality

  • Love Your Lake - The Big Windermere Survey, took place on Sunday 26 June 2022, with 100 volunteers sampling water at various points around the lake and its tributaries. The results will help experts at Lancaster University and the Freshwater Biological Association to produce the largest ever one-day snapshot of conditions in Windermere. The next survey will take place in November 2022.  Read the results of the first survey.
  • South Cumbria Rivers Trust is working with volunteers to restore reed beds around the north of the lake, encouraging natural processes to remove nutrients from the lake sediment.
  • The Lake District Foundation and Environment Agency is working with owners of septic tanks to develop community emptying schemes and share tips about how to best manage private sewerage systems. Look out for 'Call of Nature' information.
  • United Utilities is working with food outlets and restaurants in and around Windermere with tips to avoid constricting sewers with fatty waste which can lead to sewage spilling into the environment.
  • South Cumbria Rivers Trust and the Environment Agency are trialling innovative technology that if successful could be used to remove nutrients from septic tank effluent at a relatively low cost.
  • The Environment Agency will take samples and monitor water quality at four bathing water locations on Windermere until the end of the bathing water season in September, while farm inspections across the catchment will continue to focus on reducing diffuse pollution.

Love Windermere partnership partners:

Windermere water quality FAQs:

1. Is there untreated sewage in Windermere?

Treated sewage waste (effluent) is discharged into rivers and streams that feed into the lake from United Utilities Waste Water Treatment Works in the main towns of Ambleside and Windermere, and a number of smaller treatment works (operated by United Utilities) around the wider catchment.

There is a permitted discharge of untreated but screened sewage for storm overflow into the lake at Glebe Road, Bowness-on-Windermere, and at Ambleside. These are regulated by the Environment Agency.

There are also private residential and commercial sites with their own treatment facilities. These range from basic septic tanks to ‘package plants’ that offer a higher quality of treatment. General binding rules establish how these discharges should be managed.

2. What is the National Park Authority doing to protect the lake?

We are part of the “Love Windermere” partnership - the biggest ever cooperation of sectors to tackle challenges in the lake. This evidence-led programme includes a range of actions from partners, which the National Park Authority is supporting, such as the Big Windermere Survey. The strategies set out in our 2020-2025 new Partnership Plan, the management plan for the Lake District, provide a context for this.

3. What are water companies doing to improve water quality in the lake?

United Utilities has worked to reduce phosphate concentrations in the final treated effluent from all of their sewage treatment works in the Windermere catchment, from 2mg per litre in 1990 to 0.25mg per litre in 2020. This reduction has come about from the most recent improvements at Ambleside Waste Water Treatment Works, Windermere Waste Water Treatment Works and at the Glebe Road pumping station. Between 2020 and 2025 United Utilities are investigating the impact on water quality of the storm sewage overflows from within the catchment to provide the evidence for future improvement schemes. Take a look at the United Utilities plans for Windermere.

Between 2020 and 2025 United Utilities is investigating the impact of the highest-spilling storm overflows throughout the North West region to provide the evidence for future improvement schemes. Read more about combined sewer overflows.

4. I’ve seen the blue-green algae in the lake, is the water safe and clean enough to go in?

Algal blooms occur naturally in bodies of water, and some such as blue-green algae can be toxic to humans and lethal to animals. The algae area, or blooms, are usually in one part of the water and not all blooms are toxic. However, it's impossible to tell if the algae is the dangerous kind just by looking at it, so it's best not to enter the water if you suspect there is algae. Look out for local information next to the lake or check the Environment Agency’s map for reported algal blooms.

Read more about the current algal blooms (cyanobacteria) in this statement from the Freshwater Biological Association, UK Centre for Ecology and Hydrology and Lancaster University.

You can also use the Centre for Ecology and Hydrology’s ‘Bloomin Algae’ app to record and report any bloom you spot.

5. Can dogs go in the lake?

Yes, but be aware of localised occurrences of blue-green algae.

Read more in the answer above.

6. What’s the impact on fish and wildlife?

High nutrient concentrations (including phosphate in treated sewage effluent and from other sources such as applied fertilisers), can result in a process called eutrophication, leading to increased growth in naturally occurring algae. This can lower the concentration of dissolved oxygen available for fish, as well as smother spawning grounds and prevent light reaching aquatic plants changing the plant communities in the lake.

7. Are septic tanks causing problems?

There are approximately 1500 residential properties within the lake catchment that aren’t connected to the sewer network which use a septic tank or package treatment plant for sewage and waste water treatment. A number of larger sites, such as hotels, caravan parks and campsites, are also not connected to the sewer network. These sites have permits to discharge treated sewage effluent to watercourse or soakaway. The individual impact on water quality of each of the sites spread throughout the catchment is very low but the cumulative load can potentially be significant.

Any new septic tank or non-mains drainage are subject to planning approval and the National Park Authority’s Local Plan. Applications for planning permission should be supported by a full assessment of the proposed use of septic tanks, to confirm that no adverse effects will arise from the installation. This assessment should focus on the likely effects on the environment, amenity and public health.

8. Does farming and agriculture run-off affect the water quality?

Monitoring by the Environment Agency hasn’t highlighted any significant hotspots from agricultural pollution. However, studies in the catchment show that agriculture does contribute to phosphate levels in Windermere impacting upon water quality. The Environment Agency offers advice and guidance on best farming practice, preventing pollution and is working with farmers to reduce the impact of their land management on water quality. The Farming for Water Rules require good farming practice to avoid water pollution and benefit farm businesses.

9. What can I do to help?

There are many things which residents and users around the lakes can do to reduce the persistence of algal blooms in lakes, including:

  • Checking the condition and regularly emptying septic tank systems. Help is available through Call of Nature
  • Regular checking and emptying of holding tanks on boats to prevent pollution
  • Using phosphate-free cleaning products
  • Reducing fertiliser on lawns, gardens and farmland that can ultimately end up in the lake – and pay attention to the forecast – don’t spread if it’s going to rain.
  • Support your local Rivers Trusts and wildlife groups.
Windermere from Brant Fell copyright Dave Willis

Southern Windermere Trail

We're creating a new multi-user trail  for people to walk, cycle, wheel or scoot the entire length of England's largest lake, and to visit attractions along the route in a sustainable way.

Family in a rowing boat on Windermere

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Places to visit, things to do, boat hire, walking routes and bike hire around Windermere.