Where does the duty to adopt apply?
Under Schedule 3 of the Flood and Water Management Act 2010, subject to conditions imposed, the Local Authority must adopt SuDS that serve 2 or more properties.
Where does it not apply?
The duty to adopt does not apply if the system serves a site which is controlled by a single person or two or more persons together, as defined in regulations.
Examples of development types are detailed below:
- Residential buildings with multiple flats.
- Single dwelling house
- Retirement complex
- Office or commercial building
- Industrial development or commercial estate
- School or university campus
- Sports club
- Hospital or other medical facility
What will we adopt?
In adopting the SuDS system, the SAB should take responsibility for the whole system (which may include features such as pipes and underground stores as
well as green features such as swales) until flows leave the system to be either reused, or enter the ground or a surface water body or the sewerage undertaker’s network.
Adoption conditions that must be satisfied?
The SAB is required to adopt drainage systems which satisfy certain conditions. The adoption duty does not apply to SuDS that serve single properties or publically maintained roads.
The conditions that must be satisfied are:
- that the drainage system was constructed and functions in accordance with approved proposals, including any conditions of approval, and
- that the drainage system is a “sustainable drainage system”, meaning those parts of a drainage system that are not vested in a sewerage undertaker under a section 104 agreement of the Water Industry Act 1991.
Once the terms of the approval have been met, including any period required for the establishment of vegetation, the SAB can decide to adopt the drainage system itself or respond to a request from the developer. Any requests for adoption must be determined by the SAB within 8 weeks. Failure to do so within this time, will be taken as refusal to adopt unless there is already an agreement in place with both party's to extend the time frame.
Maintenance and Funding
The developer is expected to develop and produce in partnership with the SAB a maintenance plan and the means of funding for the scheme for its design life.
Where the SAB has a duty to adopt it is ultimately responsible for ensuring the adopted drainage system is maintained in accordance with statutory SuDS Standards.
In relation to securing agreements to support maintenance arrangements, including any commuted sum or maintenance funding, the SAB may wish to rely on existing powers available to local authorities under local government legislation.
In order to ensure consistency throughout Wales we recommend the use of the industry standard guidance “Commuted Sums for Maintaining Infrastructure
Assets” prepared by the CSS (County Surveyors Society), to calculate commuted sums for all drainage assets being adopted by the SAB.
For further information on Adoption of SuDS by the SAB refer to the statutory legislative document and the draft guidance by using the link below.