RSUA today responded to the Department for Infrastructure’s (DfI) ongoing public consultation on Sustainable Drainage Systems (SuDS) in new housing developments, emphasising that any future statutory requirement should recognise that nature-based SuDS should be integrated only where they are appropriate to a specific development.
The consultation’s launch followed the Water, Sustainable Drainage and Flood Management Bill passing its second stage of debate in the NI Assembly on 16 September 2025, which stands to enable the regulations proposed in the consultation document.
Ensuring suitability
RSUA considers that the consultation document aptly describes the requirement of nature-based SuDS as the “first-choice” drainage solution for new housing as an “aspiration”, rather than a blanket requirement applied irrespective of suitability.
Nature-based SuDS are well suited to larger developments with sufficient open space but are generally impractical on smaller schemes.
Considering Manual for Streets for Northern Ireland
The consultation document states that “revised guidance on layouts on roads and footways in housing developments is also likely to be needed to accommodate … nature-based SuDS at street-level”.
RSUA again advocated for the Department to consider the adoption of Manual for Streets in Northern Ireland, a comprehensive guidance document that regards drainage as a core function of the street.
SuDS Approval Body
A key proposal of the consultation is the introduction of a SuDS Approval Body (SAB), which would be responsible for approving the design and construction of nature-based SuDS.
RSUA considered that the most appropriate body to assume this role would be the Department itself, as it has the greatest level of in-house expertise and resources.
We also stated that the cost of administering the SAB could be met by developers through an application fee, similar to existing planning fees.
SuDS maintenance
RSUA suggested that maintenance could be directed and funded by the body normally responsible for the upkeep of the development as a whole (i.e., a management company by requiring residents to pay a new SuDS component as part of the overall maintenance charge already payable by property owners).
In cases where only the Department or NI Water possesses the appropriate expertise and resources to undertake this maintenance, they should be expected to do so, including ensuring that they have sufficient funding to carry out this work effectively.
Further engagement
Our full consultation response can be viewed here.
If you have any questions or comments about our response to this consultation, please contact Curtis Large, RSUA Policy and Public Affairs Officer, at curtis@rsua.org.uk
