United Utilities supercharges treatment processes for tourist season

We caught up with Andrew Kendall, county business leader at United Utilities, to discover just how the company turns on tourist mode and prepares for lots of extra visitors to Windermere every day.

Andrew, please can you tell us more about your role?

I’m responsible for all things wastewater in the county. I am a proud Cumbrian and started my career as an apprentice at United Utilities back in 2001, with my first day being at Windermere wastewater treatment works. When you flush the loo it’s likely you don’t think too much of it, but for us, this is just the start of our journey. We use world-leading technology to treat your wastewater to the tightest standards, before returning it to the environment.

United Utilities is offering tours around its Windermere treatment works. (Image: United Utilities)

When do your preparations for the busy summer season begin?

Our preparations start around eight weeks before Easter at which point we slowly add ammonium sulphate into our treatment process. Adding this helps the microorganisms in the process adapt to increased levels of ammonia before the extra visitors arrive. We call these the “good bugs”.

These “good bugs” eat the nutrients and clean the water for us. With specific conditions these bugs grow and multiply, removing ammonia and treating the wastewater.

The more bugs we have cleaning the water, the quicker we can send the wastewater to the next stage of the treatment process.

New media added to filters at Windermere wastewater treatment works to get ready for more visitors (Image: United Utilities)

How does the volume differ during peak tourist season?

Our wastewater treatment works are sized to treat the sewage from maximum population numbers at peak times and use the highest treatment standards including phosphorus removal and UV treatment to kill bacteria.

What extra processes do you have at Windermere to ensure treated wastewater is bathing water quality?

The final step before we return the water to the environment is to give the water a suntan! Believe it or not UV technology is very effective at killing bacteria. This is an extra level of treatment we’ve installed to protect Windermere’s four bathing waters.

We shine UV light tubes into the water (just like the light bulbs you would find on a sunbed). We have sensitive monitors constantly measuring how clear the water is and how much flow there is.

This tells the plant how many banks of ultra-violet light bulbs need to be switched on in order to zap enough light energy into the treated sewage to kill the bacteria.

This final stage of treatment makes sure the treated wastewater is of the highest quality before it returns to the environment.

We are really pleased that the four bathing sites in Windermere have once again been rated excellent by the Environment Agency in the latest round of classifications. The results of this are based on samples taken from each of the four sites, Fellfoot, Lakeside YMCA, Millerground Landing and Rayrigg Meadow, throughout the bathing waters season which runs from May to September.

If you’d like to come and see what we do in action for yourself, we’re still running our treatment works tours at Windermere. More than 100 of you have already paid us a visit. Email windermere@uuplc.co.uk to book your place.

What does United Utilities have planned to further improve Windermere’s water quality?

We’ve got big investment plans for four sites around Windermere which are being developed right now. We are investing an additional £41m investment into the Windermere catchment with £19m of that being spent over the next two years to further reduce storm overflows around Windermere at Elterwater, Hawkshead, Ambleside and Near Sawrey, reducing spills by 50% on 2022 figures.

At Ambleside, Elterwater and Hawkshead we’re planning to build storage tanks which together will be large enough to hold around 11 million litres of storm water – the equivalent of more than four Olympic-sized swimming pools. This extra capacity works towards reducing the amount of spills from storm overflows during heavy rainfall events.

While at Near Sawrey we’re developing a surface water separation scheme. This will see rainwater diverted away from the sewer network to a Sustainable Drainage Solution (SuDS) feature in a landscaped area where it will be able to soak away into the ground naturally, freeing up capacity in the sewer network and at the local wastewater treatment plant. Plans will be submitted for all projects this summer, with work expected to start next year.

In the meantime, our engineers have been working to see what can be done right now, including bringing some older tanks back into operation to hold storm water. These tanks are now on standby to stop up to 40,000 litres of storm water going into Windermere. Over the year that’s going to reduce the number of storm spills. These tanks will remain in use until the new solution is completed in 2027.

In addition to this work at Windermere, we also have a multi-million-pound project underway at Staveley to enhance the infrastructure and we’re fast-tracking new solutions at 28 sites across the North West this summer, including Cark-in-Cartmel.

Our work will increase treatment and storage capacity, limiting the chances of the works becoming overwhelmed during periods of heavy rainfall and reducing the number of times the storm overflows at these locations will operate, helping to reduce storm overflow spills by 60% over the decade to 2030.

To find out more about United Utilities’ action plan for Windermere visit: unitedutilities.com/windermere or pop along to the United Utilities Information Centre on 8 Cresent Road, Windermere, LA23 1EA.