• Nathan Rowe

Don’t let flood risk dampen your development opportunities!



The importance of considering climate change and flood risk in building development proposals is now more prevalent than ever, as demonstrated in recent years by the significant storms that have struck across the country.


Local planning policy for development applications quite rightly now consider drainage and SuDS proposals as a key driver in determining planning permission. Across many planning authorities, the requirement for SuDS applies to all types of development, whether on brownfield or greenfield sites and for minor and major developments.

The need for a fully detailed SuDS strategy, flood risk assessment and drainage design for all major applications at submission stage is a given, however a common misconception is that the need to apply SuDS policy to smaller projects does not apply. This is simply not the case, and we are finding that we are often brought in at a later stage, after planning permission has been applied for, to retrospectively incorporate a SuDS strategy to a developed scheme. These projects can range from small scale retail stores to residential extensions, where space is almost always limited. Even on small brownfield sites, many planning authorities now require a reduction in discharge rates to match greenfield run-off, or as close to.


A key point to consider is that we as engineers and developers have a responsibility to improve on current flood risk (on and off-site), rather than simply maintaining the status quo.

The days where drainage design is only considered to be pipes and manholes are now gone, and it is crucial that civil engineers are brought onboard as early as possible to work with architects to drive site layouts and provide support on potential locations for above-ground SuDS. These types of SuDS solutions such as the overflow lagoon pictured above, located just outside of Subteno’s office, provides not only flood storage but also improves biodiversity, water quality and visual amenity to the local community.


How Subteno Can Help ?

Subteno are experts in drainage and infrastructure design. As such engaging with us early in the design process ensures a fully considered SuDS solution to the complex challenges that sites can present. Subteno are well versed and experienced in developing designs that meet the requirements of both regional and national planning policies and frameworks, allowing us to produce outline schemes for feasibility studies or land acquisition evaluations that we can follow through to detailed design and construction.

With this expertise, we’re able to engage with Lead Local Flood Authorities before any planning application is submitted, allowing for many questions to be answered and solutions agreed in the early project stages, alleviating many headaches that occur as part of the subsequent statutory consultation process. This early consultation process can help avoid tricky planning conditions, thereby expediting the start-on-site date.

We work with developers of all sizes to help realise their aspirations for a site, whilst simultaneously developing drainage strategies that ensure an ongoing low flood risk, to both site users and the public (downstream of the site). The environment is at the forefront of our designs and as such we always ensure the required SuDS treatment train is implemented to remove pollutants from run-off before it leaves the site boundary. Look out for our upcoming blog where we use a case study to show how even the most constrained sites with complicated ground conditions can have effective drainage design implemented to reduce flood risk and provide suitable treatment measures to stormwater run-off.

What we can offer? Using the latest technology and knowledge, we work with clients ranging from popular high street retailers and nationwide distribution centre operators to regional housebuilders and individual property owners to deliver the following:

  • Site-specific Flood Risk Assessments in accordance with the NPPF

  • Detailed SuDS and Drainage Strategy reports with supporting calculations and drawings

  • Environmental Impact Assessments and Environmental Statement Chapters

  • Feasibility studies to support costing or land acquisition reviews

  • Cut & Fill terrain modelling & analysis to drive a zero-to-landfill approach

  • Standalone Drainage/SuDS designs to satisfy pre-existing planning conditions


Get in Touch!

Do you have a project that you wish to discuss? Please get in touch for a no obligation discussion.


solutions@subteno.co.uk