Industry News
Contain the Rain Garden | FloodRE
26th May 2026. By Simon Crowther FCIWEM,Director | Flood resilience &placemaking
Flood Re invited FPS director Simon Crowther to Chelsea Flower Show on 21 May,for their Contain the Rain Garden,designed by John Howlett and built by Acacia Gardens. On paper it is a compact urban plot drawing on Persian and Moroccan design. In practice it is one of the clearest demonstrations of surface water management going,and it does not contain a single pump,tank or flood barrier.
Many people,including plenty in planning and development,still picture flood risk management as hard engineering. Walls,pumps,big concrete tanks underground. Those things have their place. But they are the last line,not the first,and they are not always how you build a place people actually want to be in.
What the garden actually does
Strip away the planting and the garden is doing three simple things. It catches rain where it falls. It slows the water down. It lets it soak into the ground instead of firing it straight at a drain.
In a dense town or city,rain lands on roofs,paving and compacted ground and has nowhere to go,so it runs off fast and overwhelms the drains. Surface water flooding is the result,and it is now the largest single source of flood risk to property in England. The fix is not always a bigger pipe. Often it is giving the water somewhere to sit and somewhere to sink.
Howlett’s garden does that with layout,materials and planting rather than engineering you can see. Which is exactly what the national standards now ask for.
The policy bit,briefly
The National Standards for Sustainable Drainage Systems set out a clear hierarchy:manage runoff at or close to the surface,as near to where it lands as you can,using planting and features that do more than one job. Discharging to a pipe sits near the bottom of that hierarchy,not the top. Since the December 2024 NPPF,the expectation to deliver SuDS applies to all development,not just major schemes.
SuDS,when they are done properly,are not ugly
This is the part FPS will happily get evangelical about.
There is a lazy assumption that drainage is the boring,invisible part of a site. Something the engineer sorts out at the end once the architect has had their fun. The national standards are explicit that this is the wrong way round. They say surface water should be planned at the very earliest stage of design,and that where SuDS features sit on the surface,how they look should matter as much as how they work.
Good looks are not a nice-to-have bolted on at the end. They are part of the standard. The guidance talks about SuDS contributing to placemaking,to landscape character,to amenity and to biodiversity. A swale can be a planted feature people walk past and enjoy. A detention basin can be a green space that happens to flood on the rare day it needs to.
The Chelsea garden is the polished,show-ready version of that idea. But the principle scales straight down to a back garden and straight up to a housing estate.
Catch it
Permeable surfaces,planted beds and rain gardens hold water where it lands instead of pushing it toward a gully.
Slow it
Swales,channels and level changes give water a longer,gentler route,taking the peak off the flow.
Sink it
Soil and planting let water infiltrate slowly,recharging the ground and easing pressure on the drains.
Make it count
The same features deliver shade,cooling,habitat and a space worth standing in. One intervention,several jobs.
Why this matters beyond the show garden
Most of FPS’s work is the serious end of this. Flood Risk Assessments,Sequential Tests,getting schemes through planning and past the Environment Agency. That can feel a long way from a Persian-inspired courtyard at Chelsea. It is not.
When FPS gets involved early on a site,the questions are the same ones the garden answers. Where does the water want to go. How do you keep it near the surface. How do you use the drainage to make the place better rather than just legally compliant. Get that right at the layout stage and you avoid the expensive,ugly retrofit later,the bit where someone has to find room for a tank because nobody thought about water until it was too late.
The garden makes the case better than a 40 page report ever will:managing water well and designing somewhere lovely are not competing goals. Done properly they are the same goal.
Worth knowing
Flood Re is the joint Government and insurance industry scheme that helps make flood cover affordable for homes at risk. With over five million properties at risk of flooding in the UK,a big part of its work is showing people the practical,affordable things that reduce the impact,right down to how a garden is laid out. You can find their flood resilience advice at floodre.co.uk/rethink.
We have form here
FPS has worked closely with Flood Re before. When the industry launched Build Back Better,the scheme that funds property flood resilience after a flood so homes are repaired to be more resilient rather than simply put back as they were,FPS was part of that conversation. So seeing Flood Re at Chelsea making the same argument from the other direction,prevention through design rather than recovery after the event,was entirely of a piece.
Credit where it is due. John Howlett designed the garden (he won Gold at Malvern with his first show garden,so this is not beginner’s luck) and Acacia Gardens built it.
Thinking about water early on a site?
This is exactly the work FPS does. We help layouts manage water at the surface,hit the national standards,and come out the other side as places people want to be,not just schemes that pass.
See how we approach it:
Simon Crowther FCIWEM is the founder and director of FPS Environmental. He is a Fellow of CIWEM,a member of the DEFRA Property Flood Resilience Roundtable,and has acted as an advisor on the BBC,Sky News and Channel 4 for flood risk.
