Water and wastewater services for Kent, Sussex, Hampshire and the Isle of Wight
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Build over public sewer

By law, nobody has a right to build over, or close to, a public sewer.

*Please note: We've introduced changes to our processes from 1 August 2017 which will make them more efficient and therefore, significantly cheaper for you to submit an application to build over a public sewer.

  • We now allow you to complete a self-certification application form for £85 (+VAT)

If the proposals do not meet self certification criteria a build over application form will need to be filled out.

  • the new application fee for those who still require a Build Over agreement, will be reduced to £600 (+VAT) from £790 (+VAT)

The law

By law, nobody has a right to build over, or close to, a public sewer. In general, a minimum distance of three metres must be maintained between any building and the public sewer. However, this distance requirement may be considerably increased around deep or large diameter pipework.

Building an extension

We appreciate the desire of homeowners to extend their properties and will, in some cases, allow buildings to encroach on the public system. The decision will depend on a number of factors such as the status of the sewer concerned and therefore, each case is considered on an individual basis.

Water mains

Building over, or close to, water mains is never allowed. Neither is building over, or close to, proposed or existing sewers on new developments or redevelopments. Please refer to the guidance notes when completing your application.

Your application

If you need to complete an application form, please print it out and send your complete submission to:

Developer Services
Southern Water
Southern House
Hampshire, SO21 2SW

Alternatively, an application to divert a Public Sewer may be made.



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