Flood Risk Assessment in Taunton

A flood risk assessment in Taunton starts with the River Tone, which crosses the county town between walls and banks built after the floods of the 1960s. Streams from the Quantock and Blackdown hills drop into it on both sides. Somerset Council describes the old defences as deteriorating, and a 2026 catchment study marked surface water hotspots at the railway station and Firepool. Our consultants prepare flood risk assessments in Taunton for planning applications, for buyers and their lenders and for insurers, together with sequential and exception tests and surface water drainage strategies.

On this page Taunton means the built-up town mapped by the Office for National Statistics, in the TA1 and TA2 postcode districts: the town centre and North Town, Rowbarton, Lyngford and Pyrland to the north, Priorswood, Obridge, Halcon and the Crown Industrial Estate to the east, Holway and Blackbrook to the south-east, and Galmington, Comeytrowe and Bishops Hull to the west. Bathpool, Monkton Heathfield, Staplegrove, Norton Fitzwarren and Trull sit just beyond that line, mostly in TA2 and TA3, and share the same council, river and drainage rules. Somerset Council, the unitary council since 1 April 2023, decides planning applications and is the lead local flood authority; the wider county is on our Somerset page.

Taunton's river walls date mostly from the late 1960s and early 1970s, and enabling works for a new wall along the North Town stretch of the Tone's left bank were scheduled to start in mid-October 2026.

Ring 01293 214444 or write to enquiries@unda.co.uk with the address, and a consultant will tell you which reports a Taunton site needs.

Is Taunton in a flood zone? The Tone corridor from Silk Mills to Bathpool

Parts of Taunton are in Flood Zones 2 and 3, mainly in a band either side of the Tone between Silk Mills Bridge in the west and Bathpool in the east. The Environment Agency divides that corridor into three warning areas, graded from the properties on the riverbank to streets set further back, and runs separate areas for the Halse Water at Norton Fitzwarren and for the river below Bathpool.

Three gauges show how close the river is to those streets. At Taunton Market the Tone normally sits between 0.82 m and 1.77 m, property flooding becomes possible above 1.98 m, and the highest reading is 1.84 m, on 21 November 2012. Upstream at Bishops Hull the record is 2.59 m, set on 30 October 2000, the same day the Halse Water gauge peaked at 2.48 m. Our live river levels map shows these gauges and any warning in force, and the River Tone page follows the river from the Brendon Hills to Burrowbridge.

Looking up a TA1 or TA2 postcode

Type a Taunton postcode into the map to see the river and surface water flood zones and any warning area around it. The coral line is the town as the Office for National Statistics draws it; Bathpool, Staplegrove and Norton Fitzwarren are separate built-up areas and fall outside it. The same check is available for any English address on our flood risk map.

Walls from the 1960s and the new North Town defence

Floods in the 1960s reached more than 360 homes, shops and business premises in Taunton, and the river was widened, straightened and walled in response. Somerset Council says those works were partly upgraded in the early 1990s but are now deteriorating, and that the town had smaller floods or near misses in 2000 and 2013. It counts 1,031 properties at risk from the river in Taunton now and expects 2,548 by 2118.

• The left bank, Frieze Hill to Town Bridge. The first project replaces two stretches of the North Town bank with a reinforced concrete wall faced in brick, at about £6 million, to the 1 in 100 standard. Enabling works around Clarence Street and the BT Exchange were due to start in mid-October 2026, and the council expects the main construction to begin early in 2027.
• Firepool lockgate to the Obridge viaduct. A second project raises the lockgate and the ground around it and adds an earth bund between the Bridgwater and Taunton Canal and the river, so floodwater cannot pass into the canal and on towards Priorswood, the Crown Industrial Estate and Bathpool.
• Longrun Meadow. The third adds embankments, an inlet and an outlet to the existing storage area west of the centre, holding back river water and releasing it once the peak has passed, with benefits downstream as far as Bathpool.
• Properties covered. The council expects the three projects together to lower the risk to about 1,414 properties, among them the police station, the BT Exchange and North Town Primary School.

None of this moves a site out of its flood zone. The flood map for planning is drawn as if the defences were not there. A Taunton assessment behind the walls therefore looks at what happens if they are overtopped or fail, and our article on residual flood risk explains how that is judged. The council's scheme page and its October 2026 update on the enabling works give the current position.

Streams off the hills: Kingston, Mill Lease, Galmington and the brooks into Bathpool

The Tone is not the only source. Small streams run into it from the north and south, and Somerset Council's plans name the Galmington Stream at Comeytrowe, the Mill Lease Stream at Staplegrove, the Sherford Stream to the south and the Maidenbrook Stream at Priorswood, and in 2026 a study for Wessex Water and the council picked out the Kingston Stream down to the railway station as one of twelve surface water hotspots.

• Main river beyond the Tone. Our check of the Environment Agency's main river map shows designated main river along the streams through Galmington, Staplegrove, Rowbarton, Priorswood and Holway as well as the Tone, so the Agency, not the council, regulates works beside them. Our guide to main rivers and ordinary watercourses explains why that matters for a planning application.
• Twelve hotspots. The Taunton integrated catchment study, completed in 2026 by WSP for Wessex Water and Somerset Council, modelled surface water across the town and named hotspots including North Town and Firepool, the Kingston Stream to the station, Cheddon Fitzpaine, Trull, Norton Fitzwarren and Bathpool.
• Bathpool's flap gates. The Dyers, Allens and Maidenbrook streams come off the Quantocks into the Old River Tone at Bathpool, which can only drain through flap gates while the Tone is low; when the river is high a pump has to move the water, and the Environment Agency is planning new pumping there.
• Storage already built. A flood storage dam on the Halse Water protects the ground downstream at Norton Fitzwarren, and the storage at Longrun Meadow was built to let the town-centre regeneration sites go ahead. The Core Strategy dropped earlier plans for new dams on the Galmington and Sherford Streams in favour of strategic storage on the Tone.

In January 2026, during Storm Chandra, the Somerset Rivers Authority recorded a small cluster of properties flooded at Bathpool, and trains between Taunton and Exeter were disrupted. The SRA's summary of the catchment study lists all twelve hotspots, and our report on Storm Chandra covers the wider event.

Policies CP1 and CP8: what Somerset Council asks of a Taunton application

Taunton applications are still decided under the Taunton Deane Core Strategy, adopted on 11 September 2012, and the Site Allocations and Development Management Plan of December 2016. Policy CP1 asks for the sequential approach and the exception test. Policy CP8 goes further: it steers development away from land at risk, holds runoff to greenfield rates and volumes, and expects development sites to contribute to a strategic flood attenuation scheme for the town. Nationally, chapter 18 of the August 2026 NPPF applies, with policies F4 to F6 on when an assessment is needed and on the sequential and exception tests.

These plans stay in force until the new Somerset Local Plan replaces them; the council's timetable expects adoption in March 2029. Our Somerset Council planning page compares the policies used in each former district, and the council's adopted local plans page holds the Taunton Deane documents.

Two litres a second per hectare: runoff limits for Taunton sites

Taunton sits wholly in the Tone catchment, and Somerset's local sustainable drainage standards cap runoff in the Tone catchment at 2 l/s/ha in every storm, or the 1 in 1 year greenfield rate where that is lower. The same standards drop the national 5 l/s minimum flow and do not accept pumped drainage. That rules out a common fix on tight town-centre plots.

• Volume as well as rate. The 1 in 100 year, 6 hour runoff volume should not exceed the greenfield volume; anything that cannot soak away leaves at 2 l/s/ha or the 1 in 1 year greenfield rate.
• Brownfield plots. Where greenfield rates cannot be reached on previously developed land, the council treats it as an exception: the applicant justifies it and agrees the betterment, starting from a 50% cut in existing runoff, and proves any reused drain by CCTV survey.
• Allowances. Calculations use the Upper End climate change allowance outside drainage board districts and add urban creep of up to 10% of the impermeable area on lower-density housing, falling to none for flats.
• Soakaways first. Infiltration is tried before any discharge, so test results decide the layout; our BRE 365 infiltration rate calculator works through them.

The Somerset local SuDS design standards sit alongside policy F8 and the 2025 national standards for sustainable drainage. Foul water matters too: the Somerset Levels and Moors Ramsar site is affected by phosphates, so new homes in Taunton must show they will not add to nutrient loading, which our article on nutrient neutrality explains.

Firepool, Staplegrove and Comeytrowe: Garden Town sites and the water beside them

The Government designated Taunton a Garden Town in 2017, and most of the growth lies either on regeneration land by the Tone or on urban extensions crossed by its tributaries. For each, the council's plans leave the developable area and the drainage layout to be settled by the site's own assessment.

On sites like these, settle the sequential test first: a scheme that fails it has no use for the rest of the evidence.

From a Galmington extension to a Firepool block: which reports a Taunton scheme needs

The flood zone, the use and the size of the site decide most of it. These are the usual combinations in Taunton; we confirm the set for the actual address before quoting.

Reports for Taunton sites from Silk Mills to Obridge

Each report below is written for the Tone, the streams and the drainage limits at the address in question:

• The river and the streams together. A flood risk assessment for a Taunton site covers the Tone, the nearest stream, surface water, the sewers and what would happen if a 1960s wall were overtopped.
• For the application. Somerset Council expects a flood risk assessment for planning that answers Core Strategy CP1 and CP8 as well as chapter 18 of the NPPF, from the vulnerability of the use to a safe way out.
• Before exchange. A flood risk survey for property purchase tells a buyer on a warning-area street such as Portland Street or Acacia Gardens how the house itself sits against the river.
• Whether it should be built there. Policy CP8 points housing away from land at risk, so the sequential and exception test is settled early for any new home in the Tone corridor.
• Where the water goes. Our drainage strategy work for Taunton starts from Policy CP8's bar on raising greenfield runoff rates or volumes off site.
• Within the Tone cap. A surface water drainage strategy sizes storage to the 2 l/s/ha limit, tests infiltration first and avoids any pump the standards would reject.
• Once permission is granted. The discharge of drainage conditions assembles the calculations, exceedance routes and maintenance plan Somerset Council asks for before building starts.
• Levels behind the walls. Where a site sits behind the ageing North Town walls or beside the Galmington or Kingston Stream, flood modelling tests overtopping and sets the levels an assessment needs.
• Warnings in three tiers. With the Environment Agency warning Taunton's riverside, set-back and outer streets separately, a flood warning and evacuation plan tells occupants which warning to act on and which route to take.
• Land before it is bought. For Garden Town and regeneration land at Firepool, Wood Street or Staplegrove, a feasibility study shows how much of a parcel can be built on before an offer is made.
• Firms on the estates. The Crown and Priorswood Industrial Estates are named in the Tone warning areas, and business continuity flood planning helps a firm there decide what to move, raise or shut down when a warning comes.

Who handles flooding in Taunton, from the Tone to the sewers

If water threatens life, call 999; for a power cut call 105. After that, responsibility in Taunton is split between several bodies:

Downstream, the Tone joins the Parrett at Burrowbridge and runs on to Bridgwater, covered with the river on our River Parrett page. West along the M5, Tiverton sits on the Exe in Mid Devon, and up the coast North Somerset's largest town has its own page in Weston-super-Mare. Our full list of areas shows the other towns and counties we work in.

Questions about Taunton sites, from North Town to Bathpool

For a riverside plot in North Town, a field on the Comeytrowe edge or a house you are about to buy, call 01293 214444 or email enquiries@unda.co.uk. A chartered consultant at Unda Consulting Limited will confirm what the site needs, and a senior consultant signs off every report before it is issued.