With Sustainable Drainage Systems (SuDS) Approval Bodies (SABs) no longer being introduced, Defra and the Department for Communities and Local Government (DCLG) have made SuDs approval the responsibility of local planning authorities – but are they really best placed to take the holistic view required?

From April 6, under the new rules in England (different regulations apply in Scotland, Wales and Northern Ireland) drainage and surface water management designs will now have to be submitted as part of the planning process. The new rules mean that local priorities could mean different interpretation of the design and construction of SuDS in different local authorities.

With exemptions on smaller developments (less than 10 houses) and connection to a sewer still being an option (albeit ‘least preferred’), we can see how inconsistencies in the application of standards could arise, potentially leaving us with a piecemeal approach to sustainable drainage. Ffor many it’s a wholly unsatisfactory situation as we go into a period of accelerated construction - particularly in new house building – that will add increased pressure to the sewers and further worsen our resilience to storm water.

SuDS can be complex and they shouldn’t be assessed in isolation as they interact with surrounding and downstream sites. The DCLG has therefore indicated that it is likely that the Lead Local Flood Authority will become a statutory consultee for all planning applications on surface water management. However, unresolved questions remain on whether involvement of the LLFA will result in unacceptable delays to the planning process and what additional costs would be involved.

Neither has the thorny issue of maintenance been entirely answered in the new plan. Although the developer will be expected at the planning application stage to demonstrate how the SuDS components will be maintained effectively throughout their life, this is entirely new territory, relying on the robustness of maintenance contracts spanning decades. How does the planning authority assess the viability of the proposal?

Local authorities will only adopt and maintain SuDS that are in public open spaces, meaning that developers will need to take steps to arrange transfer of ownership and responsibility for maintenance of SuDS that do not fall under the local authority’s remit – unless the SuDS system is adopted by water companies, in more or less the same way that sewers currently are. Whichever entity adopts the system also needs a technical understanding of its function and maintenance in order to ensure that any future changes are beneficial or, at least, not detrimental. This will require community education, too: changes by an individual householder (not requiring planning approval) could have a large impact on the performance of an established SuDS system.

The Defra/DCLG U-turn on the full implementation of Schedule 3, including the introduction of SABs, is obviously a disappointment to surface water management practitioners, with the opportunity to have a clear national approach to SuDS lost. The wider, longer term view that SABs would have afforded - with experienced engineers working alongside planners to deliver the most effective, sustainable schemes - is what the UK so desperately needs, if we are to ever realise the true benefits of water sensitive urban design.

Dr David Smoker is business development director at ACO Water Management.