Changes to Sewer Adoption and Connection

Important changes to the sewer/lateral drain connection and adoption process came into effect on the 1st October 2012.

On October 1st 2012 the Welsh Government implemented important new legislation which significantly changed the way new connections to the public sewerage network are managed across the whole of Dwr Cymru Welsh Water’s operating area.

From this date all new sewers and lateral drains which are intended to connect to the public sewer network, including associated pumping stations, must be included within a Section 104 Adoption Agreement before their construction commences or a sewer connection is approved. Once the sewer adoption agreement is in place, Welsh Water must ensure that the sewers and lateral drains are subsequently adopted.

The design and construction of gravity foul sewers and lateral drains must also comply with the new Welsh Minister’s Standards, which became effective via the implementation of Section 42 of the Flood and Water Management Act 2010 on the 1st October 2012. The Standards are supplemented by a Welsh Government Guidance document which also includes Industry recommendations on how the standards can be satisfied.

The changes are intended to improve the performance and reliability of the public sewerage network in the long-term, reducing future problems which can cause sewer flooding of homes, pollution of streams and rivers and will help to ensure that customers are not exposed to any future burden for the maintenance and operation of private sewerage networks.

The new legislation follows the transfer of private sewers and lateral drains to Welsh Water on October 1st 2011. On that date ownership of most private sewers and lateral drains which connect to the public sewerage network in Welsh Water’s operating area transferred to the company. There has also been a supplementary private sewer transfer on the 1st April 2013 for sewer constructed after the 1st October 2011 and before the 1st October 2012 (implementation of the Welsh Minister Standards).

This clarified ownership and responsibility for maintenance so that our customers can now be assured that Welsh Water will deal with any problems that may arise with the sewerage networks.

The changes to the sewer adoption and connection process are intended to prevent the creation of a new stock of private sewers and lateral drains, by introducing the mandatory adoption provision for all new sewers and lateral drains (including pumping stations) that are going to connect to a public sewer network.

Section 42 of the Flood and Water Management Act 2010 has amended the Legislation which controls all new connections to the public sewerage network, Section 106 of the Water Industry Act 1991 by inserting a new requirement Section 106B. Section 106B introduces the - “Requirement to enter into agreement before construction”.

It is now a criminal offence to construct / install a sewer or lateral drains before an adoption agreement is in place. This applies whether you are connecting a new or existing property to the public sewer network for the first time, or if you are building a large development. The only exception to this requirement is if a new connection to the public sewer network is only for a drain which does not extend beyond the boundary of a property.

New surface water sewers which are intended to communicate with a watercourse are not included within either the mandatory adoption requirement or the Minister Standards. Welsh Government is in the process of considering further legislative changes via additional provisions contained within Flood and Water Management Act 2010 (Schedule 3 Sustainable Drainage) which will change the way we deal with surface water in the future. This involves the establishment of SUDs Approval Bodies (SABs).

In the intervening period we will continue to accept and process surface water sewer adoption applications for sewers which do not communicate with the public sewer network.

For further background on the commencement of Section 42 of the Flood and Water Management Act 2010 see the Welsh Government website.

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