Big North West Upgrade

Over the next five years we’re making the largest investment in water and wastewater infrastructure for a century with the Big North West Upgrade. We’re spending more than £13 billion to protect and enhance over 500km of rivers, lakes and bathing waters whilst safeguarding drinking water supplies for millions of customers.

What does this mean for Coniston?

For Coniston, it’s all about improving water quality. Over the past eighteen months we’v started to make improvements at Coniston wastewater treatment works, adding two all-in-one sewage treatment solutions to increase capacity. These units are called Moving Bed Biofilm Reactors (MBBR) and are made up of a series of compartments which promote the growth of biofilm and enhance the wastewater treatment process. We’re now able to treat an additional 40l/s, increasing the treated flow by 300% to reduce the number of spills from our storm tanks. This improves the quality of our treated water going back to the environment

So far we've seen:

• A 50% reduction in spills into the lake
• An increased Environment Agency bathing water rating at Coniston Boating Centre from 'Poor' to 'Sufficient' in 2025

But we’re not stopping there. By working with partners we’re now going even further to upgrade the works and improve water quality.

What’s next for Coniston

We’ll be taking Coniston wastewater treatment works to the next level by installing state-of-the-art wastewater treatment facilities and upgrading the equipment, allowing us to treat 3x the amount of flow we process today. Our preparation works will begin in September with works due to be complete in 2028.

As part of the upgrades you’ll see:

- New screens to help remove any unflushable items such as wet wipes or sanitary products, alongside fats, oils and grease.

- A new inlet pipe which transports the wastewater from homes and businesses into the treatment works.

- Four lamella units which aid the treatment process by separating any solids from the liquid.

- A new tertiary solids removal unit which is one of the final stages for wastewater treatment – this method catches any remaining fine particles.

- UV treatment – this is the first time Coniston wastewater treatment works will be fitted with this technology which zaps the cleaned sewage with light energy (similar to natural sunlight) and kills any harmful bacteria before the water is released into the lake. This final UV stage is an important factor for bathing waters and has helped the four Windermere bathing waters maintain the highest ‘Excellent’ rating every year

- Two new storm tanks which can together hold 2,600 m³ of excess rainwater during heavy storms – that’s the size of an Olympic swimming pool.

- Another two Moving Bed Biofilm Reactors (MBBR), bringing the total to four on site – these are made up of a series of compartments which promote the growth of biofilm and enhance the wastewater treatment process.

How our work will affect you



From September you’ll start to see an increase in working traffic around the treatment works to help us prepare for the upgrade. Our work will take place during the week with teams on-site between 8am and 6pm from Monday to Friday. If we need to work longer hours, we will advise residents and businesses affected.

As before we will need to close some of the roads to transport the new kit to the site. We’ve liaised with the Highways Authority and Parish Council to minimise the impact on the roads as we deliver this large equipment. Some of the vehicles are four metres wide and all deliveries will be made using escorted vehicles and a rolling roadblock. We will keep any residents informed of road closures over the coming months and ask you to keep highways clear of parked cars.

Deliveries will be from the A590 at Greenodd and continue to Coniston via the A5092 to Lowick Green, the A5084 to Tover, and finally the A593 to Lake Road, Coniston. Advance Warning notices will also be used on the route prior to the deliveries. Vehicles will leave the carriageway close to the Public Right of Way into the field on Lake Road. Access to the footpath will not be affected

Working with the community

This project has been designed with the local community and businesses in mind. We continue to work together to investigate unwanted infiltration to reduce the risk of flooding