29Jul 2015

The SuDS state of play

Anthony McCloy, McCloy Consulting


After a number of years waiting in the wings, the SuDS Standards finally made centre stage, but perhaps now not in the manner that many of us had anticipated. The release of the ministerial statement and updates to national planning policy requires all major schemes to incorporate SuDS; the announcement of changes enshrined in the wording “the current requirement in national policy is that all new developments in areas at risk of flooding should give priority to the use of sustainable drainage systems will continue to apply.”


In delivering SuDS there is a requirement to meet the framework set out by the ‘non-statutory’ technical standards. The use of the phrase “non-statutory” in naming the Standards has caused both confusion and consternation in some quarters. Many have taken the standards to be guidance only and therefore carry no weight. However, I have been reliably informed that the naming of the document was given significant consideration; and the use of non-statutory route was chosen to allow for future changes without enactment through parliament. There is still a very real requirement for Local Planning Authorities (LPAs) and ultimately the Planning Inspectorate to give full weight to the standards when making decision on planning applications.


The other aspect that may have been observed is that the technical standards have been largely ‘watered down’ since their first appearance in December 2011. The Government was very keen to avoid repetition across planning documents, therefore elements of the technical standards have been stripped out where they are dealt with elsewhere. What is now key is ensuring that decision makers are aware of this and have clear SuDS requirements throughout the raft of planning policies, planning practice guidelines and local policy statements. However, policies on SuDS do need to be formally adopted by LPAs in their planning documents. A few of the headlines to how SuDS may play out through the planning process are noted below.


The Government’s expectation is that sustainable drainage systems will be provided in new developments wherever this is appropriate.


To this effect, we expect local planning policies and decisions on planning applications relating to major development to ensure that sustainable drainage systems for the management of run-off are put in place, unless demonstrated to be inappropriate. The current requirement in national policy that all new developments in areas at risk of flooding should give priority to the use of sustainable drainage systems will continue to apply.


Ensure through the use of planning conditions or planning obligations that there are clear arrangements in place for ongoing maintenance over the lifetime of the development.



  • The Planning Practice Guidelines note that: “Sustainable drainage systems are designed to control surface water run off close to where it falls and mimic natural drainage as closely as possible.” My interpretation of this is that designs should incorporate source control and keep water on or near the surface.


  • Sustainable drainage systems: non-statutory technical standards – this document now focuses more on controlling the rate and quantity of flow. It is important that other aspects of SuDS delivery are not overlooked, particularly when early and effective engagement can deliver additional benefits for no additional cost.


  • Local Development Plans and Local Flood Risk Management Strategies will outline requirements for SuDS and if formally adopted these are enforceable through the planning process. However, the requirements will vary from Authority to Authority. They should not however conflict with the standards and guidance set out at national level.


The statements and supporting guidance give a clear message that sustainable drainage must be included within schemes, but as many things there is a get out clause. In this case SuDS should be provided unless demonstrated to be inappropriate or reasonably impracticable. This is probably where things will get a bit more subjective, i.e. what one designer or developer might think is impracticable (perhaps due a poor experience on a previous project) might be entirely practicable to the next….


The evidence is that SuDS are deliverable, and cost effective but only when they are considered at the outset. However, these sorts of statements within the policy and guidance are still likely to cause a bone of contention between LPA’s and developers.


However, it is accepted that the level of practicability will reduce if the drainage strategy is not considered at concept stage. This raises a bit of a dilemma, i.e. it’s not that SuDS are inappropriate for the site, delivery may just have been made more difficult due to lack of forethought. Is this an issue for the LPA, the developer or the designer?


None of this is straight forward and we do not have answers to all of the questions, for example;


  • How much information has to be provided upfront in order for the LPA to make a decision on the proposed schemes?
  • What can and cannot be conditioned?
  • What is the long term maintainability of the full range of SuDS components?


So what is the appropriate way forward?


In my opinion, developers require clarity from LPA’s in terms of what is required and what should reasonably be expected at each stage of the planning process in order for LPA / LLFA to make informed decisions. I would suggest that it is perhaps not appropriate to expect detailed design at outline planning stage, however the deliverability of the scheme should be demonstrated.


The proposals presented by developers should be clearly laid out and hopefully concise. Key aspects of the design should not be buried in a myriad of supporting information. If LPA’s and/or Lead Local Flood Authorities (LLFAs) can set out how they would like the information to be presented this may make the process easier for the Developer and LPA alike.


LPAs (supported by LLFAs) may find it useful to develop and formally adopt local standards (additional to the national technical standards) to ensure that they get the types of SuDS approaches preferable in the local setting, particularly if they are responsible for adoption and long term maintenance. Other maintenance organisations (like sewerage undertakers) are likely to have their own requirements too.


Regardless of the current concerns we can certainly say that the nettle has now been grasped. We are further forward in terms of SuDS implementation when compared with this time last year, and despite the potential period of uncertainty, the SuDS show must go on…

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