Flood Risk Assessment in Ironbridge

Unda prepares flood risk assessments and drainage strategies for commercial and residential sites across Ironbridge and the wider Severn Gorge. A flood risk assessment in Ironbridge shows your planning authority that a development will stay safe from flooding for its whole lifetime, on a stretch of the River Severn that floods more often, and more dramatically, than almost anywhere in England. We assess every source that matters here, then deal directly with the Environment Agency and Telford & Wrekin Council on your behalf.

Ironbridge sits in the bottom of a steep, wooded gorge that the River Severn has cut through coal, limestone and ironstone. That setting shapes the flood risk and the ground beneath it. We work with architects, planning consultants, developers, landowners, home buyers and businesses who need a flood risk assessment in Ironbridge for any reason: a planning application, a property purchase, a mortgage or insurance question, a BREEAM assessment, or a surface-water drainage strategy. A flood risk assessment, a sequential or exception test and a drainage strategy are three different 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.

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

Does Ironbridge flood?

Yes. Ironbridge is one of the most flood-prone settlements on the River Severn, and the riverside frontages along the Wharfage, Dale End, Jackfield and Coalport flood repeatedly. The Severn drains a vast, steep upland catchment in mid-Wales, so heavy rain there arrives at Ironbridge as a fast, deep flood peak. The Environment Agency deploys temporary barriers along the Wharfage most winters, and a permanent defence scheme is now being built through the Gorge.

• The Severn is Britain's longest river. It runs about 354 km from the Cambrian Mountains in Wales to the Bristol Channel and drains the largest river basin in the UK, roughly 11,400 km². Ironbridge sits well downstream of that whole upland catchment.
• The Gorge funnels the flood. Steep Welsh slopes and thin soils shed rain quickly, and the valley narrows through the Gorge, so the river rises fast and runs deep against the riverside buildings.
• One Lead Local Flood Authority: Telford & Wrekin Council. Ironbridge is in the Telford & Wrekin unitary authority, not Shropshire Council. Telford & Wrekin is the Lead Local Flood Authority and the statutory consultee on surface-water drainage for development here.
• February 2020 was the recent benchmark. Storms Ciara, Dennis and Jorge sent the Severn to its highest level at Ironbridge since 2000, two severe flood warnings were issued for the Wharfage, and the temporary barriers were pushed to their limit.

Check flood risk anywhere in Ironbridge

Ironbridge and the Severn Gorge are outlined below. Screen any postcode in the area 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.

Flood risk in Ironbridge: the River Severn and the Gorge

River flooding from the Severn dominates Ironbridge, but it is not the only source. The same steep gorge that makes the riverside flood also sheds surface water down its slopes and carries a long history of ground instability, so many sites here face more than one issue at once.

The Severn reaches Ironbridge having already gathered the runoff from much of mid-Wales and Shropshire. Because the upper catchment is steep with thin soils, water drains into the river quickly, and the flood peak that results travels downstream through Shrewsbury and Buildwas before squeezing into the Ironbridge Gorge. A credible fluvial flood risk assessment here has to understand that catchment behaviour, not just read a map. The named riverside areas, the Wharfage, Dale End, the Jackfield bank and Coalport, sit lowest and flood first.

• Rivers (fluvial). The River Severn is the dominant risk. The riverside frontages through the Gorge sit in Flood Zone 3, the highest-probability zone, and a more vulnerable use there will normally need a flood risk assessment and may engage the Sequential Test.
• Surface water (pluvial). Now the most widespread flood risk in England. Rain runs fast off the steep valley sides and overwhelms drains and side-channels in the Gorge. Since the 2025 PPG update, surface water on the Flood Map for Planning can trigger an assessment even on a Flood Zone 1 plot up the slope.
• Ground stability and groundwater. The Gorge is one of the most landslip-prone places in Britain. Water moving through the slope deposits feeds both the instability and the groundwater seepage seen on hillside plots, so ground conditions and flood risk are closely tied here.
• Reservoirs and canals. Raised water bodies in the wider area carry their own residual risk. The December 2025 Shropshire canal breach near Whitchurch was a reminder that these features rarely appear on standard flood maps.

Understanding which source drives the risk on a given plot is the heart of the job. Our notes on the sources of flood risk and on surface water and planning set out how these sources interact, and why a single screening map is never enough on a site like this.

Why the River Severn floods at Ironbridge

The Severn floods Ironbridge because of where the town sits in the catchment and how the Gorge is shaped. The river arrives carrying the rainfall of a large, steep upland, then has to pass through a narrow, deep gorge, so levels rise quickly and water has nowhere to spread.

Melting water beneath a glacier carved the Gorge at the end of the last Ice Age, cutting a steep-sided valley down through the local coal, limestone and iron ore. The valley sides rise from around 40 metres at river level to over 140 metres on the plateau above. That same rapid downcutting over-steepened the slopes, which is why the Gorge is so prone to landslips, and why the river runs fast and confined through the bottom of it. Upstream, work on natural flood management across the upper Severn aims to slow the flow before it reaches towns like this one, but it reduces the peak rather than removing it.

No defence removes flood risk at Ironbridge. The Environment Agency designs for a flood standard and a climate allowance, and the risk above that standard, plus the chance a barrier is overtopped or fails, is the residual risk an assessment has to address.

A history of flooding in Ironbridge

These dated events are why Telford & Wrekin Council and the Environment Agency look so closely at development in the Gorge, and why a flood risk assessment in Ironbridge has to be evidence-led rather than generic. We set out the full story in our retrospective on the 2000 Severn floods.

• 1947, 1968 and 1998. The Severn flooded Bewdley, Shrewsbury and Ironbridge repeatedly through the twentieth century. For decades flooding was treated as something to mop up rather than to plan for.
• Autumn 2000 — the turning point. After the wettest autumn on record across England and Wales, the Severn at Shrewsbury peaked at 5.25 metres at the Welsh Bridge, its highest level in over half a century, and Ironbridge was cut off as floodwater poured into historic streets. The event helped drive the reforms behind the Flood and Water Management Act 2010.
• 2007 — the regional crisis. Downstream at Tewkesbury the Mythe water treatment works was overwhelmed, leaving more than 350,000 people without clean water for over two weeks and feeding directly into the Pitt Review.
• February 2020 — the modern benchmark. Storms Ciara, Dennis and Jorge drove the Severn to its highest level at Ironbridge since 2000. Two severe flood warnings, meaning danger to life, were issued for the Wharfage, and investigations afterwards found the temporary barriers had been vulnerable to slippage where the road surface lacked grip.

A pattern runs through all of it: ground that has flooded before tends to flood again, so a credible assessment in Ironbridge treats this recorded history as evidence rather than background.

Flood defences and the Ironbridge Gorge scheme

Ironbridge has been defended by demountable barriers for two decades, and is now getting permanent defences. For a developer or owner, the key point is that defences reduce the chance of flooding but never remove it, so a flood risk assessment still has to demonstrate the site is safe behind, or above, those defences.

The Environment Agency has deployed temporary barriers along the Wharfage since around 2004, and they have held through most events while bowing and slipping under the worst of them. After 2020, the Agency and Telford & Wrekin Council improved the anchoring and resurfaced sections of the Wharfage to stop the barriers moving under load. A permanent scheme is now being delivered: Telford & Wrekin Council secured around £1.2 million over three years, including new permanent flood walls and property-level protection for roughly 40 homes and businesses in the Gorge. Around £708,000 of that was directed at reducing flood risk in the most exposed parts of Ironbridge.

• Defended does not mean risk-free. Environment Agency flood maps deliberately show the river's natural floodplain as if the defences were not there, which is why defended riverside plots in Ironbridge stay in Flood Zone 3.
• Residual risk is where schemes are won or lost. A defended-site assessment has to consider overtopping and breach, set finished floor levels with freeboard, and provide safe access and egress. Our guide to residual flood risk explains the approach the regulators expect.
• Ground stability sits alongside flooding. The 1952 Jackfield landslide destroyed houses and broke the road and railway, and Telford & Wrekin Council later stabilised a large section of the southern bank with around 2,000 steel piles, partly to stop a slip blocking the river and flooding upstream. The British Geological Survey documents the Gorge in its Ironbridge landslide case study.

Do you need a flood risk assessment in Ironbridge?

You will usually need a flood risk assessment in Ironbridge if your site is in Flood Zone 2 or 3, if it covers a hectare or more, or if the Flood Map for Planning shows a surface-water risk. Given how much of the Gorge floor sits in Flood Zone 3, most riverside development here triggers one.

The national rules come from the NPPF and its Planning Practice Guidance, applied through the Environment Agency and Telford & Wrekin Council. The September 2025 PPG update confirmed that the risk-based, sequential approach applies to every source of flooding, so a plot up the valley side that screens as Flood Zone 1 can still need an assessment for surface water. The difference between the public long-term flood risk map and the Flood Map for Planning matters a great deal on a defended frontage like the Wharfage, where the two can tell very different stories.

Climate change is not optional on the Severn. An assessment here applies the Environment Agency's allowances for higher flows and rainfall across the development's lifetime, which sets the finished floor levels, the freeboard and how much attenuation a drainage scheme needs.

• Flood Zone 2 or 3. Riverside development through the Gorge almost always needs a flood risk assessment, and a more vulnerable use may also need the Sequential Test.
• One hectare or more in Flood Zone 1. Larger sites need an assessment even away from the river.
• Surface-water risk or a critical drainage area. A mapped surface-water risk, or a critical drainage area, can require an assessment on an otherwise low-risk plot.
• A change to a more vulnerable use. Converting commercial frontage to homes in the Gorge raises the vulnerability and usually triggers a full assessment.

Planning and drainage policy for Ironbridge

In Ironbridge the local rules are set by Telford & Wrekin Council, which is both the planning authority and the Lead Local Flood Authority. Its Strategic Flood Risk Assessment and SuDS guidance tell you what a flood risk assessment and a drainage strategy have to prove here.

Telford & Wrekin Council's flood risk evidence base includes a Level 1 Strategic Flood Risk Assessment (2021) and a Level 2 assessment for the higher-risk areas, alongside its Local Flood Risk Management Strategy. As the local planning authority, it consults the Environment Agency on river flooding and acts itself on surface water and ordinary watercourses. For drainage, the Council works within the shared West Midlands SuDS guidance produced with eight neighbouring authorities, plus its own SuDS Handbook setting local standards.

• The Environment Agency is the statutory consultee for flood risk from the River Severn, and its advice on Gorge frontages carries real weight. Our guide to the Environment Agency's role in planning explains how it reviews schemes.
• Telford & Wrekin as LLFA is the statutory consultee on surface-water drainage for major development, and an unresolved drainage objection can hold an application up for months.
• The drainage hierarchy applies. A scheme has to follow the SuDS hierarchy and the 2025 National Standards, which is harder on the Gorge's steep, low-permeability slopes than on flat greenfield.
• Strategic Flood Risk Assessment. Telford & Wrekin's SFRA is the starting point for understanding which constraints apply to your site before the layout is fixed.

How Unda helps with flood risk in Ironbridge

Unda are experts on flood risk in Ironbridge and along the Severn, not a local office in the town. We act as the accurate translation layer between you, the Environment Agency and Telford & Wrekin Council, turning a difficult Gorge site into a planning-ready report.

Our consultants have prepared flood risk assessments and drainage strategies across the Severn corridor and know how the Environment Agency and Telford & Wrekin Council assess these schemes. A Senior Flood Risk Consultant signs off every report, and where national mapping is too coarse for a Gorge site we use flood modelling to pin down levels, depths and flow routes. We stay involved after the report is submitted to answer the regulators' questions, which is often where a defended-site application is finally settled.

You can read more about our team and approach on our flood risk consultants page, our coverage in the media, and the work behind our 5,000-plus assessments since 2014.

Flood risk assessments for every situation in Ironbridge

People need a flood risk assessment in Ironbridge for many reasons, and we prepare each kind to the standard its audience expects. The reports below answer different questions, so it helps to be clear which one your situation calls for.

• Flood risk assessment for planning. The report submitted with a planning application to show a site is safe for its lifetime. See flood risk assessment for planning.
• Flood risk survey for property purchase. A site-specific survey for buyers and their advisers when a search flags risk on a Gorge property. See flood risk survey for property purchase.
• Flood risk assessment for insurance. A property-level report for brokers and underwriters where cover or premiums are in question. See flood risk assessment for insurance, and our note on whether flood risk affects house prices.
• Flood risk assessment for BREEAM. Structured around BREEAM Pol 03 for project teams chasing certification. See flood risk assessment for BREEAM.
• Sequential and Exception Tests. The planning-policy case for whether development should be in a higher-risk part of the Gorge at all. See Sequential and Exception Test reports.
• Drainage strategy and SuDS. The surface-water side, showing where runoff goes and how discharge stays within limits. See our sustainable drainage strategy, preliminary drainage design and discharge of drainage conditions services.
• Working in Wales? A Welsh site needs a Flood Consequence Assessment under TAN15 instead of an FRA. The Severn rises in Wales, so this matters for cross-border work upstream.

Free tools can give you an early read before you commission a report: our Flood Risk Map screens any postcode, the Live River Levels Map shows how the Severn is behaving right now, and for drainage the geology and ground conditions checker, the drainage calculators and the BRE 365 infiltration calculator give a first pass before any infiltration testing.

Local flood risk management and emergency contacts

If you live or work in Ironbridge, these are the bodies that manage flood risk in the Gorge and the quickest ways to get a warning or report a problem. In a flood that threatens life, always call 999.

You can sign up for free Environment Agency flood warnings for the Ironbridge and Wharfage areas, and check the live picture during high water on our Live River Levels Map. National forecasting that feeds these warnings is explained in our piece on the Flood Forecasting Centre.

Frequently asked questions