Safely recycling wastewater to the environment

Our plans for the wastewater part of our business include improvements to reduce sewer flooding, tackle odour from some of our treatment works and cope with the increasing population in our region.

A significant part of our planned investment will also be targeted at building the London Tideway Tunnels - two large storage tunnels that will capture wastewater that otherwise pollutes the River Thames during heavy rain.

Many of the improvements we propose will help deal with the challenges of climate change and new environmental legislation.

Coping with population growth

We must plan for increasing development in London and the Thames Valley. By 2015, forecasts suggest there will be a further 380,000 people living in this area, in addition to the 13.6 million we already serve. Towns where the population is set to rise significantly include Swindon, Didcot, Dartford and Aylesbury.

In some towns, such as Basingstoke, we already face stringent limits on the quality of treated wastewater we discharge from our sewage works into local rivers.

We must invest to increase capacity in sewers, pumping stations and treatment works, and to cope with an estimated 263,000 new connections to our network.    

Improving river water quality

By improving treatment processes, we will also improve water quality along 246km of rivers and protect another 227km from deterioration.    

In particular, the proposed London Tideway Tunnels will bring major improvements to the tidal section of the Thames, by collecting sewage which otherwise overflows into the river during heavy rain. We aim to build the first of two sections by 2014, with the second scheduled for completion by 2020.    

Tackling sewer flooding and smells

Heavy rain can also bring severe problems for the small proportion of customers whose homes are at risk of sewer flooding. 

We intend to protect more than 4,500 properties and to improve the design standard of new sewers to help safeguard against the heavier storms which climate change could bring.     

We will invest in improvements to reduce the likelihood of odour problems for customers whose homes are close to our sewage treatment works.  Our proposals will benefit nearly 20,000 households in our region.

Recycling sewage sludge

Our five-year plan includes proposals for the safe disposal of sewage sludge, the solid residue left at the end of the treatment process. We intend installing enhanced treatment technology to comply with new regulations, and expand our capacity at sites including Beckton.

We will also continue promoting the generation of renewable energy, as a by-product of our treatment process. We already produce enough to power more than 90,000 homes.

Maintenance work is another important feature of our proposals. We aim to make further improvements to our sewers, lessening the likelihood, for example, of collapses and blockages.

This work is set to increase, as we are likely to be required to adopt 40,000km of private sewers, on top of the existing 68,000km we already maintain.