Flood Risk Assessment in Buckingham

The River Great Ouse runs directly past Buckingham town centre, and a flood risk assessment in Buckingham has to start from what the river has already done here. In December 2020 it rose to its highest recorded level, flooded the University of Buckingham's Hunter Street campus and left parts of the town under water for days. We assess every source that could affect a site in Buckingham — the Great Ouse, surface water, the town's sewers and, on some sites, groundwater — then take the assessment or drainage strategy through the Environment Agency and Buckinghamshire Council on your behalf.

We prepare flood risk assessments in Buckingham for planning, property purchase, mortgage and insurance, and BREEAM, alongside sequential and exception tests and surface-water drainage strategies (SuDS), for architects, planning consultants, developers, landowners, homebuyers and businesses across the town.

If you need a quote or want to talk a site through, contact one of our experienced flood risk consultants on 01293 214444 or enquiries@unda.co.uk.

In December 2020 the Great Ouse reached 2.16 metres at Buckingham, its highest recorded level, flooding 72 properties and causing more than £180,000 of damage at the University of Buckingham alone — proof that a river running through the middle of a town centre has to be assessed as carefully as any main river in the country.

Flood risk assessment in Buckingham at a glance

• The Great Ouse runs through the town centre. Streets including Chandos Road, Nelson Street, Hunter Street, Well Street, Ford Street and Glynswood Road sit inside the Environment Agency's Buckingham flood warning area.
• December 2020 was the worst flood on record. Buckinghamshire Council's Section 19 investigation recorded 72 properties flooded internally and 15 more externally, with the river gauge reaching its highest level since records began.
• Flooding here is not a one-off. The Easter 1998 floods, the July 2007 floods and Storm Bert in November 2024 all put homes, businesses and the university campus under water.
• One council now runs flood risk for the whole town. Buckinghamshire Council has been the single Lead Local Flood Authority since the 2020 unitary reorganisation, covering surface water, groundwater and ordinary watercourses.

Check flood risk anywhere in Buckingham

Buckingham is outlined below. Screen any postcode in and around the town against Environment Agency data for rivers and sea, surface water and the planning flood zones, with a climate outlook to 2125. It is an indicative first pass, not a substitute for a site-specific assessment.

Buckingham's flood history: a town that floods repeatedly

Buckingham has flooded from the Great Ouse in 1998, 2007, 2020 and 2024, and each event is officially documented rather than anecdotal. Buckinghamshire Council's own Section 19 investigations and Environment Agency records give a flood risk assessment in Buckingham a run of dated, sourced evidence that a generic report could never match.

• April 1998 — the Easter floods. Buckinghamshire Council's own comparator figure records 75 properties affected in Buckingham, though an earlier Environment Agency review put the figure at 25 houses and 5 non-residential properties.
• July 2007. The River Great Ouse flooded 70 homes and businesses in Buckingham, and around 30 people sheltered overnight at the Radcliffe Centre.
• 23–24 December 2020. The worst flood on record. The river gauge at Buckingham reached 2.16 metres, its highest recorded level. The Section 19 investigation recorded 72 properties flooded internally, 11 of them non-residential, plus 15 more flooded externally.
• 24–25 November 2024 — Storm Bert. The gauge reached 2.31 metres and more than 40 properties flooded, with Chandos Park, Bridge Street, Ford Street, Bourton Park and Cornwall's Meadow car park among the areas under water.

The University of Buckingham in December 2020

The Section 19 investigation names the University of Buckingham's Hunter Street campus among the lowest-lying, most flood-prone parts of the town, alongside Clarence Park, Stratford Fields and Bourton Park, with parts of the campus sitting in Flood Zone 3 and parts in Flood Zone 2. Buildings on Hunter Street and Mill Lane flooded from the Great Ouse, and the council's report records more than £180,000 of damage — lost stored goods, flooded basements containing IT equipment, and three written-off electric vehicles. University staff led an on-site response and then extended help into the surrounding area: the University provided three dwellings free of charge to displaced families, gave emergency accommodation to students, and ran a fundraiser that raised £18,500.

Immediately east of the campus, an established residential area near the Great Ouse and the disused Buckingham Arm of the Grand Union Canal — popular with students for its walking distance to campus, though ordinary housing rather than university-owned halls — was also affected. The Section 19 report records surface-water and sewer-surcharging risk there, and flags a flood-defence embankment whose ownership it describes as "a matter of discussion between different parties," recommending this be resolved. It is exactly the kind of residual-risk and third-party-asset issue our note on residual flood risk sets out to unpick on any site next to a defence structure.

A pattern runs through Buckingham's flood record: the same low-lying ground by the Great Ouse floods again and again. A robust flood risk assessment in Buckingham treats that record as evidence, not background colour.

Flood risk in Buckingham: the Great Ouse, surface water and sewers

The Great Ouse dominates Buckingham's flood risk, but it is rarely the only source on a site. The Environment Agency maintains two flood warning target areas over the town, surface water has overwhelmed drains in the centre as recently as 2023, and sewer surcharging has flooded at least one town-centre business. A credible assessment reads all of them together, not just the river.

• Rivers (fluvial). The Great Ouse runs through the town centre. The Environment Agency's target area 052FWFUOBUCK1 names Glynswood Road, School Lane, Nelson Street, Hunter Street, Chandos Road, Well Street, Victoria Row, Ford Street, Candleford Court, Stratford Road and Marsh Edge as low-lying areas close to the river; a wider target area, 052FWFUOBUCK2, covers the rest of the town. An upstream target area covers Thornton, Beachampton and Passenham on the same river.
• Surface water (pluvial). Buckingham Town Council's own flood-risk page confirms flooding here "occurs not just from the river but also from excess surface water that cannot drain away quickly enough," and a June 2023 event overwhelmed drainage in the town centre.
• Sewers. Anglian Water is the sewerage undertaker for Buckingham. A June 2023 case saw a town-centre business flooded with over two feet of water after drains reportedly could not cope with demand — a reminder that sewer capacity, not just river levels, drives risk here.
• Groundwater. Buckinghamshire's chalk geology creates a documented county-wide groundwater flood risk, though no source confirms a specific groundwater flooding event within Buckingham itself. Groundwater is still assessed as a source within every flood risk assessment we prepare, whatever the site — see our note on groundwater flooding.
• Flood zones vary block by block. A site-specific assessment at Market Hill found Flood Zone 1, while the University of Buckingham's Hunter Street campus sits partly in Flood Zone 2 and partly in Flood Zone 3 — proof that a single postcode search is never enough for a site by the river.

Screening a site is the first step, and our free flood risk map and live river levels map give an indicative read before a full assessment. Our note on riparian ownership is worth reading for any site with a Great Ouse boundary, since the rights and duties that come with owning riverbank in Buckingham are easy to overlook. Downstream, the same river shapes our flood risk assessment in Milton Keynes page, where engineered balancing lakes rather than a historic floodplain town centre define the risk, and further down the catchment our flood risk assessment in Bedfordshire page covers the record flooding the Great Ouse caused at Marston Moretaine in September 2024. For the wider county, see our flood risk assessment in Buckinghamshire page.

Development and flood risk assessment in Buckingham

Buckingham's growth is shaped as much by flood risk as by demand. The Vale of Aylesbury Local Plan (VALP), adopted in September 2021, allocates land in and around Buckingham as part of roughly 30,134 new homes across the wider area, and the town's own Neighbourhood Development Plan, which passed referendum in January 2026 with 94% support, sets local policy on top of it.

• Town centre and riverside sites. Land close to the Great Ouse, including sites near the university and the town centre, sits partly in Flood Zones 2 and 3, so finished floor levels, safe access and egress, and often compensatory storage have to be designed in from the outset.
• The Buckingham Neighbourhood Development Plan 2024–2040. Adopted policy includes an urban greening approach and a canalside sustainable drainage strategy along the disused Buckingham Arm, and requires that schemes do not increase surface-water risk, with a flood risk assessment expected across Flood Zones 1 to 3.
• Infrastructure-dependent sites. A housing site on Brackley Road originally proposed in the Neighbourhood Plan was dropped from VALP because it depended on a Buckingham Western Relief Road that will not now be built — a reminder that access and drainage infrastructure, not just the flood zone, can decide whether a site is developable.
• Town centre regeneration. Buckingham Town Council and the Buckingham & Villages Community Board have been working on plans for the town centre since 2023, and any scheme in the historic core close to the river needs its flood risk resolved alongside heritage and access constraints.

Climate change is not optional in Buckingham. An assessment has to apply the Environment Agency's climate change allowances for higher river flows and rainfall over the development's lifetime, generally 100 years for housing, which sets floor levels, freeboard and how much attenuation a drainage scheme needs.

Homebuyers and businesses come to us too, not only developers. A flood risk question can affect a purchase and house prices, and a standard conveyancing search is not the same as a planning-grade or homebuyer-grade assessment of the actual building. Knowing which you need saves time and avoids paying for the wrong report.

Planning policy and your Lead Local Flood Authority in Buckingham

Two authorities set the rules for a flood risk assessment in Buckingham. The Environment Agency leads on the Great Ouse. Buckinghamshire Council has been the single Lead Local Flood Authority (LLFA) for the whole county, including Buckingham, since the 2020 unitary reorganisation replaced the former Aylesbury Vale District Council — it now leads on surface water, groundwater and ordinary watercourses.

Your flood risk assessment and any drainage strategy have to satisfy national policy — the NPPF and its Planning Practice Guidance — and the local framework: Buckinghamshire's Local Flood Risk Management Strategy, its Strategic Flood Risk Assessment, and the Local Plan and Neighbourhood Plan policies that apply to Buckingham specifically. Where a higher-risk site is involved, the Sequential and Exception Tests apply, most recently shaped by the September 2025 PPG update. On drainage, Buckinghamshire Council's own surface water drainage strategy guidance and the 2025 national SuDS standards set out what the council expects to see.

What your flood risk assessment in Buckingham must show

• Risk assessed from every credible source that applies to the site, using the Flood Map for Planning and Buckingham-specific data such as the EA's target areas and the Section 19 reports.
• An appropriate location, tested against the Sequential Test where policy requires it.
• Safe for its lifetime, once the Environment Agency's climate change allowances are applied.
• No increase in flood risk elsewhere, with attenuation and, where needed, compensatory storage for any Great Ouse floodplain land lost to the scheme.
• Residual risk managed, with safe access, egress and finished floor levels — especially where a site sits behind a defence or embankment, as our note on the flood risk assessment process explains.

How Unda helps with flood risk assessment in Buckingham

We act as the accurate translation layer between your scheme and the requirements set by the Environment Agency, Buckinghamshire Council and national planning policy. We are experts on Buckingham's flood record, not a generic report mill working from a single postcode search.

A flood risk assessment in Buckingham from Unda assesses every credible source — the Great Ouse, surface water, sewers and, where relevant, groundwater — compares modelled flood levels against your proposed floor levels, sets safe access and egress, and recommends mitigation the Environment Agency and Buckinghamshire Council will accept. Our consultants are members of the Chartered Institution of Water and Environmental Management (CIWEM), including Chartered Water and Environmental Managers, and Unda is a CIWEM Business Partner. A senior consultant signs off every report. Where the council needs it, a surface-water drainage strategy sits alongside the assessment as a separate report, so the two cases stay consistent and an objection has nowhere to land.

Flood risk assessments for every situation in Buckingham

A flood risk assessment, a Sequential or Exception Test and a drainage strategy are three distinct reports. They often travel together in a planning submission, but they answer different questions: is the site safe, should the development be here, and where does the surface water go. We prepare all three in Buckingham, alongside the right form of assessment for buyers, lenders and BREEAM.

Flood risk assessments

• Flood risk assessment for planning. The core report, site-specific and prepared to satisfy the NPPF, the Environment Agency and Buckinghamshire Council. Groundwater and, where needed, flood modelling are assessed within it rather than as separate reports.
• Homebuyer and property-purchase survey. For conveyancing, where a search has flagged Great Ouse or surface-water risk and you need the actual building assessed, not a broad map.
• Flood risk assessment for insurance. Property-specific evidence for brokers and underwriters where premiums have risen or cover has been restricted after events like December 2020.
• Flood risk assessment for BREEAM. Structured around BREEAM Pol 03, which is credit-driven rather than safety-driven, so a planning FRA alone rarely satisfies it.
• Groundwater flood risk. A defensible design water table for any Buckingham site with a basement or soakaway, assessed as a source within the FRA or as a standalone hydrogeological assessment on complex sites.

Sequential and Exception Tests

The Sequential and Exception Tests are a separate, locational report about whether a development should be in a higher-risk part of Buckingham at all. The Sequential Test defines an area of search, identifies reasonably available lower-risk sites and justifies the proposed site; the Exception Test is the second gate where development still needs to proceed. A clean site-specific assessment showing the development is not actually within an area at risk, as the Market Hill example above did, can remove the need for the test at application stage.

Drainage strategy and SuDS

• Sustainable drainage strategy (SuDS). Surface-water engineering — calculates existing versus proposed runoff and proposes SuDS to hold discharge within Buckinghamshire Council's standards, including the Neighbourhood Plan's canalside approach.
• Preliminary drainage design. The early, outline read that flags infiltration issues before they affect layout and land value.
• Discharge of drainage conditions. The detailed stage to discharge a pre-commencement or pre-occupation drainage condition.
• Flood modelling. 1D and 2D hydraulic modelling — a technique that feeds the assessment, Sequential Test or drainage design where national mapping is not enough for a Great Ouse-side site.

Early in a drainage strategy it helps to know whether the ground will take water: our free geology and ground conditions map and BRE 365 infiltration rate calculator give an indicative read before a trial pit, our note on infiltration testing explains when it is required, and the drainage calculators help size the scheme. Our guides to the four pillars of SuDS and to what a report must cover are a good starting point, and our note on what an assessment costs helps with budgeting early.

Local flood risk management and emergency contacts in Buckingham

The most reliable Buckingham flood information comes from the lead authorities. For an immediate threat to life during a flood, always call 999; for a power cut during flooding, call 105.

• Check for flooding in Buckingham. Environment Agency live warnings, river levels and maps at check-for-flooding.service.gov.uk; sign up for flood warnings or call Floodline on 0345 988 1188.
• Buckinghamshire Council — Lead Local Flood Authority. Surface water, groundwater and ordinary watercourse flooding, plus drainage strategy guidance, at buckinghamshire.gov.uk.
• Anglian Great Ouse Regional Flood and Coastal Committee. Regional investment and priorities across the Great Ouse catchment via the Anglian Great Ouse RFCC.
• Flood Action 4 Buckingham (FA4B). A local flood action group formed after the 1998 and 2007 floods, with an emergency plan and annual exercises — background via this Climate Just case study.
• Live river levels. Check whether the Great Ouse is running high right now via our live river levels map or the Environment Agency's Buckingham gauge.

For wider background on how these bodies fit together, our notes on the Pitt Review and its legacy since the 2007 floods, and on residual flood risk, are a good starting point. We publish a full set of local area guides covering flood risk across the rest of the country.

Flood risk assessment in Buckingham: frequently asked questions