Water Industry News

United Utilities Publishes North-West Sewer Revamp Road Map

The UK’s ageing sewer network poses a significant problem around the country, leading to water leaks, pollution and flooding. The situation is being exacerbated by population growth, with the system unable to cope with this additional pressure, as well as with more frequent and extreme weather events being driven by climate change.


Serious investment is required on the part of water suppliers to ensure that the network is fit for purpose, regardless of how old the pipes actually are. There are more than 500,000km of sewers across England and Wales, many of which are in dire need of upgrades to help reduce sewage spills.


To this end, a new National Overflows Plan was announced in May last year, with £10 billion set to be invested in modernising the sewers to reduce spills in rivers and seas.


Furthermore, a new national environmental hub is due to launch this year, providing information on all 15,000 overflows around the country to drive up transparency and ensure that utility companies are held to account.


The aim is to increase the capacity of sewage treatment works so that they can treat higher volumes of rainfall and sewage, replace non-permeable surfaces like concrete with ponds and grass to help reduce surface water runoff, use nature-based solutions like wetlands and reed beds to treat overflow spills, and enlarge and improve pipes so they can carry more sewage during peak times, as well as fixing misconnected pipes.


Spotlight on the north-west


To fulfil its responsibilities in this regard, United Utilities has just published its roadmap demonstrating how it intends to deliver cleaner rivers, lakes and beaches all over the north-west, with the multi-billion pound investment the biggest of its kind in the UK.


There are over 2,200 storm overflows across the north-west, designed to prevent flooding by ensuring that water has somewhere to go when the sewers are full during heavy rainfall. Since December last year, each of these sites have been monitored so that the energy company can see how often they operate and which ones should be dealt with first.


The ambition is to ensure that storm overflows operate less than ten times a year by 2050, with this new regional plan expected to cost around £19 billion. Work is already underway at the highest priority sites, with over 430 storm overflows expected to be improved come 2030.


For example, temporary treatment and storage facilities have been installed in Cargo in Cumbria, with results since August 2023 showing that the number of spills have already been reduced from 343 annually to just a single occasion.


In Chorley, meanwhile, new storm storage tanks have been built at the Horwich wastewater treatment works and the sewer network, driving improvements across 38km of the River Douglas. As for Ecclestone, a new wetland is now being created to filter and clean stormwater before it makes its way back to the Syd Brook.


And in Bolton, £38 million is being invested to reduce the number of times storm overflows are used during periods of heavy rainfall from sites in Dunscar Bridge, Astley bridge and the Firwood industrial estate.


Jo Harrison, United Utilities asset management director, said: “At United Utilities, our purpose is very clear… we don’t just supply water, we also want to make the north-west greener, stronger and healthier.


“The multi-billion pound programme we are now embarking upon will see the biggest overhaul of the region’s sewer network in a century. Not only is this now enshrined in law, it is what our customers expect and it’s the right thing to do.”


She went on to add that fundamental changes are now being made to how the sewer system is designed – but this cannot take place overnight.


The drainage systems are now being replumbed, storage tanks are being built to increase capacity and the power of nature is being harnessed so that stormwater can be treated before being returned to the environment… all of which takes time. However, work has already begun and much more of this will be seen over the next 25 years.


Specific programmes & initiatives


As well as focusing on the biggest storm overflow investment plan in the UK, United Utilities is engaging in one of the largest environmental improvement programmes ever, with a dedicated rainwater management team seat up to ensure that rainfall and surface water are handled more effectively.


New ways of dealing with excess water during periods of heavy rainfall are now being considered, with pipes separated out to reduce the number of combined systems, alongside the installation of new storage tanks and nature-based solutions to prevent overflows into rivers and stopping flooding of homes and businesses.


Plans include investing £146 million in sustainable rainwater management solutions in Greater Manchester, protecting 125 miles of cleaner rivers to support wildlife and biodiversity, and encouraging developers to prioritise sustainable drainage solutions in new developments.


Nature-based solutions are also a top priority for the utility company, including catchment management, source water protection, wetland restoration, natural flood management, water harvesting, afforestation, sustainable drainage systems and agricultural best practice.


Such activities will enhance the natural water cycle by regulating rainwater flow, facilitating natural sedimentation and filtration processes, keeping nutrients and sediment in the soil, improving both biodiversity and human wellbeing alike.


Finally, sustainable drainage systems are being prioritised to help manage rainfall through the use of planted or constructed features, which can slow rainwater runoff down in a similar way to natural drainage, thereby reducing the amount of pressure being put on the region’s drainage system.


How can businesses help?


There’s a lot that businesses can do to reduce pressure on the network, everything from raising awareness among the workforce to not flushing wet wipes and rags, maintaining septic tanks, preventing water leaks, rainwater harvesting, investing in permeable paving, using eco-friendly cleaning products and so on.


If you’d like to find out how to reduce water usage and consumption across your business site, get in touch with the Switch Water Supplier team today.