05Feb 2016

Barriers to nationwide SuDS delivery

Anthony McCloy, McCloy Consulting

Things have certainly progressed over the last ten years that I have been delivering SuDS training. The increased level of technically challenging questions from delegates is keeping me more on my toes for one thing. The SuDS triangle has also become the SuDS square as part of the recent SuDS manual update.

However, some things remain the same. Many still do not agree whether the acronym should contain a large U or a small u. More importantly, SuDS has still not become the norm in terms of providing drainage for new or redevelopment schemes. It has always been stated that this is likely to be a generational shift, the question is now which generation this is likely to occur in.

To make any real progress we must first try and address the reasons as to the continuing barriers to change. I have listed out what I believe to be some of the primary barriers. However, I also believe they are surmountable and have provided a suggested route to overcome. I would like to open up the discussion to others who may have similar (or opposing) thoughts on the matter.

Preconceptions – despite the numerous attempts to debunk myths – such as; SuDS cannot be used on clay sites; SuDS require extensive land take; or, SuDS cost more – these myths are still common place. The worrying aspect is that reasons for not doing SuDS are quoted in professionally produced documents which are submitted for planning, with many rationales for SuDS technique selection sounding entirely plausible until you start to scratch the surface.

Action – preconceptions around SuDS which are not based on sound logic needs to be challenged wherever they exist. Simply stating; unsuitable geology, unsuitable terrain and onerous land take requirements are more of an indication of the lack of SuDS appreciation of the individual making the statement than the applicability of SuDS to the site.

Education – having provided guest lectures in universities over the years, there is still some way to go in terms of how SuDS is addressed within many of our academic institutions. Perhaps SuDS is seen as something that is better addressed through Industry.

Action – we need to establish more ways for graduate and undergrads to gain a wider appreciation of the subject outside of their own individual fields. Better appreciation of the subject should also extend into our secondary and primary schools.

SuDS design standards (or lack thereof) – We are still dealing with a suite of design details that were developed with piped drainage in mind. Largely these do not lend themselves well to a shallow SuDS design.

Action – We need to develop new details that are acceptable to local planning authorities (LPAs) and over time these must be collated into a new set of design standards that will facilitate SuDS delivery. We cannot expect entirely bespoke drainage details on every scheme; that said, a bit of diversity from time to time should be encouraged.

Tendering process – As an engineer I am acutely aware that where the tendering process is biased towards price, this puts pressure on minimising the amount of time that is then spent on delivering the design. Unfortunately for SuDS, the ‘lowest cost wins’ tender model is counterintuitive as it takes considerably more time to produce a SuDS design that is integrated with the landscape, and carefully considers each change in level when compared with a pipe design with attenuation.

Action – those procuring SuDS design need to carefully consider what they wish for the end product and ensure that the tender specification is robustly worded, even if the bias is towards lowest cost.

Legislative enforcement – With implementation of the SAB now a distant memory, the responsibility for SuDS delivery now resides with local planners. In the experiences of many local authorities simply prescribing a requirement for SuDS by way of planning condition very often delivers an attenuation tank at the end of a pipe.

Action – Planners and lead local flood authorities (LLFAs) need to clearly spell out what they want to see in terms of SuDS delivery on their local patch. Decision makers should appreciate that SuDS delivery encompasses a wider remit of multiple benefits rather than only ensuring the flood risk is not increased. They need to find ways of expressing this within documents that are embedded within the local planning system.

Adoption – We all understand that adoption is a fragmented process and whilst not an engineering barrier, it is an institutional one. The adoption issue was identified as the elephant in the room a long time ago, but it is an issue that has never been fully tackled, demonstrated most recently with Government throwing it back in the laps of decision makers (the LPAs). It looks like management companies will take up the slack and it will be interesting to see how this model develops.

Action – this is a difficult one so I have left it until last. Ultimately, it is in the hands of the LPA’s, LLFAs(and / or Water Authorities) to establish a model that works using existing or updated existing legislative instruments. The usefulness of management companies cannot be discounted, but it would be encouraging to see LPA’s take up a much more involved role. Sceptics will also note that the risk with management companies is that if they can get away with a reduced maintenance approach by not replacing items or a reduction in regular tasks, they will to save costs. Contracts and performance specifications need to ensure that they can be held accountable if the receiving environment is deemed to be at risk (from water quality or quantity) from a neglect of duty to maintain the SuDS installations and associated flow control structures.

It would be a significant step forward if we would formalise a way that LPAs can be paid for the management and upkeep of SuDS systems to facilitate nation wide adoption.

In short, I don’t have all of the answers and I am sure that there are other barriers that I have not identified, but hopefully this provides some food for thought.

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