Recently, the former Secretary of State for Environment, Food and Rural Affairs, George Eustice, told British Water's 'Creating a more sustainable water sector' conference: "never mind the newts and the bats and NIMBYS who sit on councils that seem to always get the blame for the fact that housing is not being built quickly enough", water scarcity is "the most pertinent and earliest challenge" now confronting developers.

Advising commercial and residential developers, we share Mr Eustice's concerns about the capacity of utilities infrastructure. Statutory connection rights and the duties of statutory undertakers to keep pace with infrastructure demand should serve to prevent development constraints. However, there is increasing pressure on aging infrastructure, and a problem arguably even more significant than water supply: foul water drainage.

In this article, we explore the issues with the current sewage infrastructure that are preventing developers from connecting to local sewage networks and slowing down the construction of new homes.

Statutory duty to plan ahead

Sewerage undertakers have a statutory duty under Section 94(1) of the Water Industry Act (WIA) 1991 to ensure effective drainage and sewerage systems.

This duty includes:

  • providing, improving, and extending public sewers and maintaining them to ensure the area is effectively drained.
  • the undertaker must make provisions for emptying these sewers and dealing with their contents through sewerage disposal works or other means.
  • undertaker must enhance the sewerage system to meet foreseeable increases in demand and prepare drainage and sewerage plans every five years.

This requirement to plan for increased capacity requirements was set on an explicit statutory footing by the Environment Act 2021, which added additional sections to the WIA requiring sewerage undertakers to prepare drainage and sewerage plans every five years (reviewed annually and updated if necessary). Undertakers must assess current capacity and actions needed in 5, 10 and 25 year periods to ensure that capacity keeps pace with demand.

The requirement to produce drainage and sewerage plans came into force on 1 September 2024, although the first round of drainage and sewerage plans was produced on a non-statutory basis in 2023. The forward planning measures contained within them were used to inform the 2024 price review.

A right to connect (irrespective of available capacity)

Landowners have a right under Section 106 WIA 1991 to connect and discharge foul water into public sewers.

Undertakers can only refuse a connection on limited grounds relating to the mode of construction or condition of the connection. Insufficient capacity is not a valid reason to refuse a connection.

Constraint through planning conditions

Even if there is insufficient capacity in the local sewerage network to support new development, the sewerage undertaker can't refuse a connection, but it can object to a planning application. And an objection on the basis that the local sewerage network will be overloaded is not something that councils can easily ignore.

The courts have found (Yns Mon Borough Council v Secretary of State for Wales and Jones Brothers (Construction) Company Ltd [1993] JPL 225) that it is not reasonable for a council to refuse planning permission on the grounds of insufficient sewerage infrastructure. However, as sewerage spills are clearly not in the public interest, councils can impose planning conditions to delay discharge into the public sewers until the required sewerage capacity is available.

It is increasingly common to see Grampian conditions attached to planning permissions that restrict occupations until enhancements to the sewerage network have been made by the sewerage undertaker. The delivery of these enhancements to the network is outside of the developer's control and consented development is delayed, leaving developers and communities frustrated.

Future outlook

By objecting to planning applications on the basis of insufficient foul water capacity, sewerage undertakers are effectively admitting to being in breach of their forward planning duty under section 94(1) WIA. But neither the Local Planning Authority nor the developer has any direct legal recourse in respect of a breach of section 94(1) duty. It falls to Ofwat to impose penalties, and their attention is more focussed on the immediacy of storm overflow discharges than forecasting failures and the planning process.

However, new statutory sewerage and drainage plans are a step in the right direction. They are still in their infancy, and it remains to be seen how effective they will be in ensuring that foul drainage capacity keeps step with development needs and preventing sewerage from being an unsavoury blockage in the development pipeline.

To discuss the issues discussed in this article further, please contact our Planning team.

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