UK councils suffer on average 43 flooding incidents a year, with nationwide recovery costs of up to £566 million, according to findings from Infrastructure Policy Advancement (IPA), the policy think-tank at Bentley Systems Inc. More than half of councils (57%) also reported that their sewer systems had been overwhelmed in the last decade.

The IPA think-tank examined data from 382 district, borough, and county councils across the UK, and found:

• On average, councils that reported costs had spent £100,063 on repairs and cleanup following the most recent flood, or up to £4,320,749 a year. Extrapolating across all 131 councils that tracked the number of floods, gives a nationwide cost of £566,018,221.
• Councils’ average annual flood remediation budget for 2025 is £637,559 – meaning repairs and cleanup for a single flood costs 16% of the entire annual budget. Flood remediation budgets have fallen from an average of £728,170.46 in 2024, representing a 12% drop of £90,610.62.

Mark Coates, vice president, Infrastructure Policy Advancement at Bentley Systems said:

“Floods have a huge impact on the UK economy, creating a sizeable black hole in public finances. But they have a much more profound effect on people’s everyday lives. Last year alone saw multiple floods with catastrophic human impact, and more than 400,000 people in Europe had their homes and businesses damaged by flooding.

“We must act now to shore up defences as urbanisation and extreme weather mean floods are becoming more frequent and more severe.”

The data shows that almost all councils (92%) are, or are planning to, implement flooding remediation measures, with Sustainable Drainage Systems (SuDS) the most popular. SuDS approaches reduce flooding with minimal or no damage to the environment; including permeable paving, green roofs, rain gardens and retention ponds that enable greater surface water runoff by mimicking natural drainage systems.

Almost three quarters of councils (74%) require all new builds or developments to include SuDS, whilst 64% of councils are installing their own systems. Other approaches councils have/are adopting in include:

• 59% are enhancing green spaces to improve drainage and act as a natural buffer, and the same number are planting trees to help absorb excess rainwater.
• 55% are increasing drainage maintenance to enable better water flow.
• 38% are engaging with home and landowners to reduce paved space, improving natural drainage.

“Councils are doing what they can to prevent flooding – from SuDS initiatives to expanding green spaces and improving drain maintenance – but they need more support. While the government plans to take the lead in overhauling drainage standards, increasing budgets alone won’t solve the underlying issue,” Coates continued: “We’ll only see real change through holistic collaboration across public and private sectors. Now is our opportunity to lead a national rollout of SuDS, which can be paramount to unlocking more sustainable, resilient, liveable urban environments.”

The IPA, in coordination with British Water and Aqua Consultants, recently launched a white paper, Creating Sponge Cities to Tackle Surface Water Flooding, which addresses pluvial, or surface water flooding—one of the greatest flood risks to UK homes and businesses—and the urgent need for resilient, nature-based infrastructure. The report cites as extreme weather events triggered by climate change have become more common, the risk, regularity, and cost of pluvial flooding have all increased.

The analysis was based on public data collected from UK district, borough, and county councils during the first half of 2025.

Click here to download Creating Sponge Cities to Tackle Surface Water Flooding