Flood risk assessments for planning in the Cotswolds – the Windrush, Evenlode, Coln, Leach and Churn catchments and the limestone plateau’s rapid-response rivers.
The Cotswolds generates a higher volume of FRA work relative to its population than most rural areas of England. The combination of attractive market town settings, significant development pressure, narrow valley floodplains and a geology that creates both rapid surface water runoff and unpredictable groundwater emergence makes flood risk a routine planning consideration across Witney, Burford, Chipping Norton, Charlbury, Bourton-on-the-Water, Stow-on-the-Wold, Moreton-in-Marsh, Chipping Campden, Cirencester and the smaller villages throughout the AONB.
The Cotswolds’ rivers rise quickly. The Windrush through Witney, the Evenlode through Charlbury, the Coln through Fairford, the Churn through Cirencester, the Leach through Lechlade, all drain the oolitic limestone plateau rapidly after intense rainfall. The combination of impermeable agricultural land, stone-walled fields and limited natural attenuation means that valley bottom settlements can flood with relatively short warning. The speed of onset is material for finished floor level calculations in FRAs for these settlements, not just the eventual flood depth.
“A Flood Risk Assessment should be an engineering exercise, not a template report. At FPS Environmental every assessment is bespoke, focused on assessing flood risk thoroughly and supporting viable development.”
Simon Crowther BEng (Hons) FCIWEM C.WEM MIET
Director, FPS Environmental
The River Windrush drains from the high wolds south of Bourton-on-the-Water through Burford to Witney, where it meets the upper Thames corridor. Witney has significant Flood Zone 2 and 3 areas from the Windrush. Bourton-on-the-Water, despite its tourist-friendly water features, has documented flood risk that planning applications in the village must address. The West Oxfordshire SFRA sets out the assessment requirements for the Windrush catchment and must be engaged with directly in site-specific FRAs.
Groundwater flooding from the Jurassic and oolitic limestone geology is a specific and distinctive feature of Cotswolds flood risk. The limestone aquifer holds significant volumes of water that emerges as springs and distributed seepage during and after prolonged rainfall. This emergence is often diffuse – it does not come from a specific watercourse or spring but from the ground surface across a wider area. Standard fluvial flood zone maps do not capture this risk. FRAs for sites in the Cotswolds where BGS groundwater susceptibility mapping indicates risk must assess groundwater emergence as a distinct flood source.
The Cotswolds straddles multiple county boundaries – West Oxfordshire, Gloucestershire (Cotswold District and Stroud), South Warwickshire and North Wiltshire. Oxfordshire County Council acts as LLFA for West Oxfordshire sites. Gloucestershire County Council acts as LLFA for Cotswold District and Stroud sites. Each authority applies its own SuDS requirements and drainage guidance. FRAs and drainage strategies must engage with the LLFA for the specific district the site falls within.
• Development in Flood Zone 2 or 3 along the Windrush, Evenlode, Coln, Leach, Churn, Glyme or any tributary
• Development in Witney, Bourton-on-the-Water, Burford, Charlbury or other valley settlements where Windrush or Evenlode floodplain risk applies
• Development where groundwater flooding from Jurassic limestone geology is identified in BGS susceptibility mapping
• Development of 1 hectare or more in Flood Zone 1
• Development requiring a surface water drainage strategy under OCC, GCC or other relevant LLFA guidance
• Development in settlements where rapid catchment response creates short flood warning lead times
We understand the Cotswolds’ specific flood risk characteristics, rapid limestone catchment response, groundwater emergence from the oolitic aquifer and the cross-boundary governance structure across multiple county LLFAs. These are not standard national planning requirements and require specific local knowledge.
We cover the whole Cotswolds AONB and its fringe settlements across West Oxfordshire, Cotswold District, Stroud, South Warwickshire and North Wiltshire. Our Oxfordshire page covers the broader county context; this page focuses on the specific Cotswolds catchment characteristics.
Our FRAs engage with EA Windrush, Evenlode and Coln model data and address groundwater flood risk from the limestone geology as a specific and distinct assessment requirement.
Years combined civil & environmental engineering experience
Years delivering drainage, design and risk advisory
Projects including individual assets valued at £1 billion+
Drainage design and flood risk commissions delivered
Here are some of our latest testimonials from satisfied clients. If you’d like to discuss your requirements further, please don’t hesitate to get in touch.
We are a charity owning a large parcel of land where gathering water is then affecting neighbouring properties. Received expert flood risk and drainage advice from FPS Environmental Ltd. All dealings with them were timely and professional. Site visit arranged where we were able to fully discuss causes and solutions. Great peace of mind obtained from engaging their expertise.
Michael Rowell
Landowner
The report I received was for a Flood Survey which was very thorough and clearly a lot of work had gone into it. The team were always available and conscious of deadlines. I would definitely recommend them if you are looking to get a flood survey completed.
Mike Gray
We spent thousands of pounds on poor quality investigations before reaching out to FPS Environmental. Most surveyors over promised and underdelivered creating tremendous stress for me and my family. FPSE has been absolutely amazing from the very beginning. They treated us with respect and restored our faith in this industry. We are incredibly grateful to them and highly recommend the company to anybody who wants to get a top product and piece of mind.
George Albota
I have used FPS, Simon and his team on several occasions over the last few years to advise on the flood risk and mitigating factors on both houses and prospective businesses. They have deep expertise and contacts across the spectrum of flood management. In particular, I have found their assessment reports invaluable. Whilst they are understandably busy, they are good to deal with and I would have no hesitation recommending them to anyone who is looking for advice in the sector.
Richard Warburton
Business Owner
FPS was really helpful in providing consulting advice in connection with a residential property acquisition. Sebastian from FPS undertook the survey and followed up with a full report and a consultation call to run through everything. The basic desktop data suggested a high flood risk, but this property-specific survey allowed us to take a well-informed position following Sebastian’s advice. Great work – and he and the FPS team were really helpful throughout the process. I’d certainly recommend them.
Richard Brandon
Very impressed with FPS Environmental Ltd and the guidance we have received to date. We had an hour long online consultation with the principal surveyor, and it was extremely helpful and productive. Thank you FPS. Will use the company again and highly recommend.
Helen Sutherland
FPS were able to work to our schedule and fit in an appointment at short notice. There was great communication from the office staff keeping us informed of any changes or requirements before the site visit.
The site survey was very thorough and Simon very knowledgeable, and quite happy to answer all questions. The provided report was extensive with usable information and recommendations. I will use FPS in the future and happily recommend them to all of my clients.
Drew Kirkland-Crawford
Deadwood Services Ltd
Send us your project brief and we will come back with a scope and indicative fee. Where additional input is required, this is provided on a formal instruction basis.
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