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27 Aug 2018

Mixed Review for Sustainable Drainage

Posted in Blog posts

The Government has published its review of whether new major developments are adding to flood risk or not.

The key is whether current law encourages them to design ways to handle heavy rainfall onsite, rather than pour it down already overloaded drainage channels, mix with sewage, and potentially cause devastating flooding for people and wildlife.

The current law only applies to around 1 in 10 new developments, those classed as “major”. Notably, the review didn’t consider what was happening in the other c90%, nor the opportunities missed to manage flooding through creating manmade wetland features that benefit wildlife too. WWT’s Senior Government Affairs Officer Hannah Freeman has more:

The value of sustainable drainage systems (SuDS)  is that if they are designed and maintained appropriately they can deliver a range of multiple benefits which traditional drainage systems can’t. It is the crux of this which is completely missing from the Government’s Review of Sustainable Drainage Systems, published last week.

We do welcome the conclusions which focus on the role industry bodies can play in filling a very real skills and knowledge gap and the recognition that Government has a role to play in clarifying responsibilities around adoption and maintenance. However there are a number of key points made in the report which are ignored in the concluding remarks.

On the ground delivery

It is great to hear that SuDS are predominantly written into local development plans as a requirement for major new development and ensuring that development applications include SuDS elements. However, given that 70-75% of Local Planning Authorities (LPAs) have no monitoring or reporting of the take-up of SuDS and are under increasing resource constraints, we understand that it is often difficult for planning officers to ensure planning conditions are met.

High quality SuDS

The report noted that Lead Local Flood Authorities (LLFAs) were concerned that SuDS were not being incorporated at the master planning stage, with a lack of detail and consideration at early planning. Although SuDS can be retrofitted at later stages of planning they are often squeezed into current designs. If considered earlier in the design process, SuDS can be included much more cost-effectively into developments and are much more likely to incorporate multiple benefits and be of a higher quality.

There is no mention of quality at all within the report and this reflects planning policy more widely. It is not only about the quantity being delivered but the quality. People want high quality housing and this means green/blue spaces. Housing developments rich in green and blue spaces can offer substantial health and wellbeing benefits as well as supporting community cohesion and sense of place. Planning policy must put more priority on delivering high quality homes and SuDS. Even in high density areas this can be achieved, as can be seen in the Netherlands.

SuDS standards

The Government has published voluntary standards for SuDS. However, the review did not look at whether the SuDS in development were applying these standards.

So what’s the plan?

The Government has committed to a 25 Year Environment Plan for England. It calls for more SuDS to help deliver environmental benefits in the urban environment. These environmental benefits will only be seen through delivery of high quality SuDS. We welcome the new National Planning Policy Framework promoting multi-beneficial SuDS where possible.

However, without mechanisms to monitor delivery; ensure SuDS are included within master planning/early design; create mandatory standards which reflect multiple benefits; or indeed make certain the skills are available to plan for and deliver them, how is Government going to ensure this goal in the 25 Year Environment Plan is going to be met?

WWT will be working with Government going forward:

  • to make improvements to National Planning Policy Guidance to better promote high quality SuDS delivery in new developments;
  • to seek a Government review of the SuDS standards to consider making them mandatory (as they are in Wales) and incorporate the delivery of multiple benefits
  • to advocate for a scheme to monitor the uptake of SuDS.