We promise to dispose of your wastewater

Every time one of our customers has a bath or flushes the loo, the wastewater is carried through a vast underground sewer network to one of our 571 wastewater treatment works to be cleaned and returned safely to the environment.

Since privatisation, we’ve invested heavily in our sewer network to improve its capacity and performance. However, there is still more to do in order to deliver the wastewater service our customers expect.

In particular, sewer flooding remains a major issue. We recognise that this has a big impact on quality of life for those affected. Flooding can be caused by blockages or collapses in a sewer, or by heavy rainfall which can overwhelm the sewer system.

Increases in population over the past few decades, as well as the replacement of natural drainage with concrete and paving, have also placed more demands on our ageing sewer system

Recent investment means our sewer network is performing better than ever before, while our work to reduce blockages and collapses is also having a positive effect. Information campaigns to encourage customers to help reduce blockages, by avoiding putting inappropriate materials down the sink or loo, are playing a positive role too.

However, there is still more to do to make our wastewater service more resilient.

What customers and stakeholders have told us

In recent conversations with our customers and stakeholders, the need to tackle sewer flooding and reduce pipe blockages were the most common issues highlighted.

Feedback included

  • Customers have said we need to do more to reduce the risk of sewer flooding – but at an acceptable cost for bill payers.
  • Our work to remove wastewater efficiently, safely and responsibly is valued highly by customers
  • Regulators and stakeholders would like us to work more collaboratively with other organisations in efforts to tackle flooding, and to take a strategic, risk-based approach
  • More than three quarters of stakeholders would like to see the number of sewer collapses and blockages reduced
  • Customers want us to plan ahead to meet risks posed by climate change, such as intensive periods of rainfall which are becoming an increasingly common weather feature
  • There is an important health perspective; the last thing anyone wants is sewer water affecting properties.


What we'll achieve

A reliable wastewater service

We’ll manage our sewer network and treatment works to ensure we dispose of wastewater without our customers ever noticing. We’ll also look after private sewers which were previously owned by our customers and we’ll work more closely with developers to ensure our service remains reliable.

Reduced sewer flooding risk

We’ll reduce the risk of homes and businesses being flooded, by ensuring our network is resilient to severe weather events.

Our proposals for the next 25 years:

Service improvement
Maintaining service

In the years ahead, we still need to invest to build extra capacity into our sewer network but we’ll also find alternative, less costly ways to improve performance. We’ll also play our part to provide a reliable wastewater service by working in partnership with other organisations.

Tackling sewer flooding can be expensive, but by taking an innovative, partnership-led approach, we believe we can deliver marked improvements while avoiding significant increases in customer bills.

Our focus will be on:

Fixing flooding at source

We are convinced of the need to place a greater emphasis on tackling the root causes of flooding, such as reducing the flow of storm water entering the sewer network, to ensure our customers are less likely to be flooded. By re-introducing natural green areas such as ponds and soakaways into the urban environment, we can allow excess storm water to soak naturally back into the ground rather than entering our sewers where it might cause flooding and pollution further downstream.

Working in partnership

By collaborating with other organisations such as local authorities, we can tackle sewer flooding more effectively. Joint working, sharing experience, knowledge and resources all helps to deliver a better outcome for customers and the environment. This is something we will do more of in the future.

Changing behaviours

We will continue to run information campaigns to encourage customers to avoid flushing inappropriate items such as baby wipes down the loo, or pouring fats and oils down the sink. It is estimated that around a third of sewer blockages are caused by this behaviour, resulting in many flooding and pollution incidents. We will continue to provide inspiring education and engagement programmes to encourage customers of all ages to become more aware of these everyday issues.

Modernising our network to provide a better service

No-one’s home or garden should ever be flooded with sewage but eliminating sewer flooding entirely would be prohibitively expensive. However, we recognise the need to improve on our current level of performance, for the benefit of our customers and the environment. We will roll out a new sewer network monitoring system which will allow us to spot and clear blockages and stop things escalating before flooding occurs.

Building resilience for the future

Population growth and climate change can all place increased pressure on the sewer network. We need to ensure our sewerage system is equipped to cope with a changing and uncertain future in a more sustainable way. Therefore, we will work with local authorities and developers throughout the local planning process to ensure we meet future demand.