Flood Risk Assessment in Coventry

A flood risk assessment in Coventry usually starts with water you cannot see. The River Sherbourne runs in culvert under the ring road and the city centre, the River Sowe winds through the eastern estates, and surface water gathers along the roads between them in heavy rain. Our consultants prepare flood risk assessments in Coventry for planning applications, purchases, mortgages and insurance, with sequential and exception tests and surface water drainage strategies alongside them. Reports for sites in Coventry come from Unda Consulting Limited, a CIWEM Business Partner.

On this page Coventry is the urban area the ONS draws for the city, cut at the city council's boundary. South of the centre that means Earlsdon, Stivichall and Finham; to the west, Canley, Tile Hill and Allesley; to the north, Coundon, Radford, Holbrooks and Foleshill. Wyken, Walsgrave, Binley and Willenhall make up the east, along with Spon End and Chapelfields beside the centre, across the CV1, CV2, CV3, CV4, CV5 and CV6 postcode districts. One council decides applications here and also acts as the flood authority. Towns beyond the boundary have pages of their own, such as Leamington Spa, or sit on our Warwickshire page, and the full list is under the areas we cover.

Coventry's Local Plan asks for a flood risk assessment on any site within 20 metres of a watercourse, and its setback rules apply to culverted rivers too. Under the city centre that means the buried Sherbourne can shape a scheme even where no river is in sight.

Call 01293 214444 or email enquiries@unda.co.uk with a Coventry address, and one of our flood risk consultants will say which reports the site is likely to need.

The Sherbourne under the ring road: why the city centre needs a closer look

The Sherbourne rises in fields north of Allesley and flows south-east to the ring road, where it goes underground at Spon End. It reappears east of the centre near Gosford Street and Gulson Road, then runs south through Lower Stoke and Whitley to meet the Sowe at the city boundary. Local history accounts date most of that enclosure to the 1960s, and the river now runs beneath shops, roads and car parks.

• The 1900 New Year flood. On the night of 31 December 1900 the Sherbourne broke its banks across the town. The London Daily Graphic of 2 January 1901 reported that the lower parts of Coventry were completely submerged, and local accounts describe Godiva Street running like a river and Queen Victoria Road as one long canal.
• Streets the SFRA names. The 2022 Strategic Flood Risk Assessment lists properties at river risk along Pavilion Way, the Arches Industrial Estate, Spon End, Sherbourne Street, Windsor Street, Meadow Street and Corporation Street, with Flood Zone 2 reaching further than Flood Zone 3.
• Surface water on top. The same study maps large surface water flow paths through the commercial streets around Queen Victoria Road and Corporation Street, and along Hales Street and Fairfax Street on the east side of the centre.
• Warnings for the centre. The Environment Agency runs separate warning areas for the Sherbourne at Allesley, at the city centre and at Pinley and Whitley, with gauges at Holyhead Road, Hope Street and Charterhouse Bridge.
• Setbacks that include culverts. Policy EM4 asks for buildings to stand at least 8 metres back from a main river and 5 metres from an ordinary watercourse, and says this includes existing culverted watercourses, so the line of a buried channel matters on a city-centre plot.

A culverted river is easy to miss on a desktop check and hard to model, because the national mapping does not show what happens if the culvert surcharges or blocks. Our guide to what a culvert is and who owns it covers the consent and maintenance questions, and the Sherbourne's three gauges can be followed on our live river levels map.

Looking up a CV postcode on the city map

A CV postcode typed into the map below brings up the Agency's flood zones, surface water extents and reservoir areas for that part of the city, and our flood risk map does the same for any English address. Coral marks the built-up city, cut at the council boundary, which leaves Baginton and the airport, Ansty Park and Burton Green outside it. Keresley village and the green belt edges belong to the city but lie outside the shaded area. The national layers do not show the culverted Sherbourne's behaviour or the council's own flood records, so a result is a starting point, not an answer.

Sowe, Sherbourne, Canley Brook and Hall Brook: which parts of Coventry each one reaches

The SFRA names the Sherbourne and the Sowe as Coventry's main rivers, both under the Environment Agency, and describes the Sowe's floodplain as the widest because the land along it is low and flat. Both drain south to the Warwickshire Avon and on to the Severn. Smaller brooks feed them from the estates, and two canals cross the north of the city.

The Agency's gauges and warnings cover the Sowe, the Sherbourne and the Canley Brook, and a single flood alert area spans all three with the Finham Brook. Whether the Agency or the city council has a say on works beside a stream turns on its status, as set out in our note on main rivers and ordinary watercourses. For a site beside one of the canals, our note on why breach data is hard to get sets out what an assessment can rely on.

Allesley, Upper Eastern Green and the floods Coventry has recorded

The city's flood record is dominated by the Sherbourne's upper reaches in the west and by short, heavy storms in the centre. The Agency's historic flood outlines touch the city only at Tollbar End, where the Avon spilled in January 1985 and April 1998; the rest of the record comes from the council.

1. 1966 to 2016, Allesley. The council lists flooding in Allesley village in 1966, 1979, 1981, 1988, 1999, 2007, 2008, 2012 and 2016, most recently inside homes on Butt Lane and Washbrook Lane. In 2018 it put 34 homes at high risk there, 14 of them with a 1 in 5 chance of flooding in any year.
2. 2008, Duggins Lane. The council's preliminary flood risk assessment records 25 properties affected by surface water at the junction of Duggins Lane and Station Avenue in Tile Hill.
3. 6 February 2016, across the city. Prolonged heavy rain flooded roads and gardens in many places and the council received reports of internal flooding at eight properties. Upper Eastern Green, beside the Brookstray, flooded twice that year after an earlier event in 2008.
4. January 2024, Broad Lane. Severe rain partly flooded Broad Lane; the council says roundabout drainage works kept water out of homes in Goldthorn Close.
5. November 2025, the city centre. Overnight rain left Lower Ford Street under water in the morning rush hour, and BBC Coventry and Warwickshire reported on 12 November that blocked drains were the cause.

A storage pond upstream of Allesley was dropped in 2018 when its estimated cost rose from £1.7 million to £5 million. Instead the Environment Agency, the council and Warwickshire Wildlife Trust built a natural flood management scheme on the farms above the village, with 58 leaky barriers, five retention pools, 70 trees and 1,800 metres of hedgerow, and fitted resilience measures to 26 Allesley homes. The council says no Allesley property reported flooding inside during the record wet months of June 2019 to February 2020. The council's scheme page gives the detail, and our article on leaky dams explains why storage of this kind trims smaller floods more than the largest.

Policies EM4 and EM5: what Coventry City Council looks for in an application

Coventry City Council decides planning applications and, as lead local flood authority, has been a statutory consultee on drainage for all major schemes since April 2015, with a non-statutory say on minor ones. The flood rules sit in the Local Plan adopted in December 2017, and two of them, the 20 metre trigger and the 600 mm floor level, ask for more than national policy does.

A replacement plan is on its way. The Local Plan Review was submitted on 9 September 2025, examined at hearings from March to June 2026, and the consultation on main modifications closed on 1 October 2026; until the council adopts it, EM4 and EM5 are the policies applications are judged against. The council's review page carries the latest stage. Our explainers on Flood Zone 3b and which climate change allowance to use show how the indicative 3b and the 40% rainfall figure work through into a layout.

Qbar minus 20%: drainage rules on Coventry sites

Coventry sets its discharge limit below the greenfield rate, so most schemes need more storage than a plain greenfield-rate limit would ask for. EM5 also asks every development to test the ground before infiltration is ruled out, which brings site investigation forward in the programme.

• Below greenfield. Where infiltration is not possible, runoff is limited to Qbar greenfield minus 20%, or 5 litres a second if that is greater, under the council's standing advice.
• Test the ground first. EM5 asks for infiltration tests and a groundwater risk assessment with seasonal groundwater monitoring, so that infiltration is shown to work, or not, before a watercourse or sewer is proposed.
• Source protection zones. The SFRA identifies four groundwater source protection zones in the west of the city, at Spon End, Mount Nod, Green Lane and Keresley, where soakaways may be restricted to protect drinking water.
• 40% on rainfall. Storage is sized with a 40% climate change allowance on rainfall unless a lower figure can be justified against the national guidance.
• Exceedance routes. The council wants flood routes for exceedance and blockage shown on the plans, kept away from buildings and emergency access and never routed through private gardens.
• Room to maintain. Open attenuation features need a maintenance strip of at least 3 metres, rising to 5 metres where one adjoins a watercourse.

The council's pre-application service covers drainage and flood risk for applicants who want an early view. Our explainers on source protection zones and the SuDS hierarchy cover the two questions that decide whether a Coventry site can use soakaways.

From a Coundon extension to a Keresley housing site: when a flood risk assessment in Coventry is needed

Because EM4 adds the 20 metre watercourse rule and a surface water trigger to the national flood zone tests, more Coventry sites need an assessment than the flood map alone suggests. These are the common cases; send us anything that does not fit one of them.

The national tests are explained in when an FRA is needed, and sites where the threat is the road and the drain are covered in our guide to surface water flooding and planning.

Reports for the Sherbourne corridor, the Sowe valley and the city's estates

A buyer in Allesley, a developer at Keresley and a firm on the Stonebridge Trading Estate each need something different. Each report is written by one of our chartered consultants, and none leaves the office until a senior consultant has reviewed and signed it.

• Culvert, river and roads together. A flood risk assessment for a Coventry site weighs the buried Sherbourne, the Sowe and its brooks, the surface water flow paths along the roads, the canals and the sewers.
• The 20 metre rule. Coventry City Council asks for a flood risk assessment for planning within 20 metres of any watercourse and where drainage problems are known, as well as in Flood Zones 2 and 3.
• Buying in Allesley or the Sowe valley. Where a search flags a home on Washbrook Lane or near Binley Road, a flood risk survey for property purchase checks the building against the river levels and the recorded floods before exchange.
• Unallocated brownfield land. EM4 applies a sequential and exception test wherever a scheme in Flood Zones 2 or 3 is not on an allocated site, which covers much of the city-centre infill along the Sherbourne.
• Reviewed by the flood authority. As a statutory consultee since 2015, the council checks each major drainage strategy against EM5 and its Qbar minus 20% limit.
• Storage below greenfield rates. A surface water drainage strategy for a Coventry scheme shows the infiltration tests EM5 asks for and the storage needed when runoff is held below the greenfield rate.
• Details left to a condition. Where the council leaves drainage details to a condition, discharge of drainage conditions supplies the calculations, exceedance routes and maintenance plan it asks for.
• Under the ring road. National mapping cannot show what happens when the Sherbourne culvert surcharges or blocks, and the SFRA uses an indicative Flood Zone 3b where no detailed model exists, so flood modelling can set levels for a site beside either.
• Seasonal monitoring under EM5. EM5's groundwater risk assessment, the shallow water table the SFRA finds along the Sowe and the Sherbourne and the four source protection zones are covered by a groundwater flood risk assessment.
• Warning and evacuation in EM4. EM4 asks for suitable warning and evacuation arrangements on sites in flood risk areas, and a flood warning and evacuation plan sets them out against the Agency's Sherbourne and Sowe warning areas.
• After repeated floods in Allesley. Homes that flooded from the Sherbourne or the Brookstray, and those fitted with resilience measures since, can show an insurer where they stand with a flood risk assessment for insurance.
• Estates in the flood zones. Before buying or lending on units at the Arches Industrial Estate, Blackburn Road or the Stonebridge Trading Estate, flood risk due diligence sets out the river, surface water and drainage position.
• Shops and offices in the centre. Premises on Corporation Street, Queen Victoria Road and Hales Street sit on the SFRA's surface water flow paths, and a business continuity flood risk assessment plans for closure and recovery.
• Commercial space at Friargate and the business parks. New offices and employment buildings aiming for BREEAM credits need a BREEAM flood risk assessment for the Pol 03 issue, written alongside the planning submission.

Culvert, river, sewer or canal: who handles flooding in Coventry

Different bodies look after the Sherbourne, the brooks, the sewers and the canals in Coventry. If anyone is in danger from floodwater, call 999 first.

The council's Local Flood Risk Management Strategy sets out how it manages flooding with the Agency and Severn Trent, and works on or beside an ordinary watercourse need its ordinary watercourse consent. Our guide to the lead local flood authority explains the council's role, and our note on LLFA objections covers the missing calculations and exceedance plans that lead to drainage objections.

Coventry site questions, from Allesley to Binley

Whether it is a semi in Allesley or a yard beside the Sowe, our consultants at Unda Consulting Limited can say what the site needs from a postcode and a sketch. Call 01293 214444 or email enquiries@unda.co.uk.