Flood risk assessments for planning across East and West Sussex, the Arun, Ouse, Adur and Rother catchments and the Channel coastline.
Flood risk is a material planning consideration across a significant proportion of Sussex’s developable land. From the low-lying coastal plain of the Arun, Adur and Ouse valleys to the chalk downland headwaters of Mid Sussex, flood risk comes up in planning applications across the county in ways that are not always obvious from the headline flood zone map.
Mid Sussex District Council published updated Level 1 and Level 2 SFRAs in 2024. A specific concern raised by the Level 2 SFRA is that poorly designed drainage on development in Mid Sussex headwater catchments can exacerbate flooding in downstream communities, including Crawley, Worthing, Shoreham and Littlehampton. Drainage strategies for Mid Sussex applications must address this cross-boundary downstream impact specifically, not just manage surface water on site.
“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 Arun has a broad floodplain through Pulborough, Arundel and Littlehampton, with documented flood history including the December 2013 and January 2014 events that affected hundreds of properties in Pulborough and the lower Arun valley. The Arun District SFRA and the West Sussex County Council drainage guidance set out the planning requirements for development in this catchment. The River Ouse flooded Lewes severely in October 2000, one of England’s most significant recent urban flood events, and the river’s flood history informs planning decisions across Lewes District. The Adur and Rother catchments present fluvial risk in their lower reaches at Shoreham and Rye respectively.
Coastal and estuarine development in Sussex requires engagement with tidal flood risk alongside fluvial sources. Chichester Harbour, Pagham Harbour, Shoreham-by-Sea, Newhaven and the Rother estuary at Rye all present combined tidal and fluvial conditions where both sources must be assessed in combination. The relevant Shoreline Management Plans divide the Sussex coast into management units with different long-term coastal management strategies, and FRAs for coastal sites must engage with the relevant SMP.
Surface water flooding is a material risk across both counties, particularly in the older built environments of coastal towns like Worthing, Bognor Regis, Hastings and Eastbourne where drainage capacity is limited. West Sussex County Council and East Sussex County Council both act as LLFA for their respective areas and apply SuDS requirements to all major planning applications.
• Development in Flood Zone 2 or 3 along the Arun, Ouse, Adur, Rother, Cuckmere or any tributary
• Coastal and estuarine development in Chichester Harbour, Shoreham, Newhaven or the Rother estuary
• Development where drainage design may affect flood risk in downstream communities in the Arun or Ouse catchments
• Development of 1 hectare or more in Flood Zone 1
• Development requiring a surface water drainage strategy under West or East Sussex County Council SuDS guidance
• Sites where the Mid Sussex Level 2 SFRA 2024 has identified specific flood risk or drainage constraints
We are familiar with the Mid Sussex Level 2 SFRA 2024, the Arun District SFRA and the planning requirements of the Sussex LPAs and both county LLFAs. We understand the cross-boundary downstream impact requirement that the 2024 SFRA introduced for Mid Sussex applications and address it specifically in our drainage strategies.
Our FRAs engage with EA fluvial and coastal model data and are prepared by qualified flood risk consultants. We cover all West Sussex districts, Arun, Chichester, Adur, Worthing, Horsham and Mid Sussex, and all East Sussex districts, Lewes, Wealden, Rother, Hastings and Eastbourne.
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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