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Questions raised about flood defence priorities

The government was this week knee-deep in criticism following its reaction to the flooding that has drenched the UK in recent weeks.

Experts on all sides blamed short-termism for a series of emergency measures announced for the Somerset Levels.

The Environment Agency has been given six weeks to form a 20-year plan for the area, up to £4M is to be spent dredging two local rivers, and moves were made to draft in the Army to help (see box).

Efforts are concentrated on the floods which are affecting just 40 properties. In contrast, Boston in Lincolnshire still awaits news of a £99M defence scheme that would protect thousands of homes. Around 65km2 of land in the Somerset Levels is inundated. The area has a vocal farming movement.

Environment Agency chairman Chris Smith waded in this week with an editorial in the Daily Telegraph. He warned that resource constraints would not allow rural and urban areas to be protected.

“Rules from successive governments give the highest priority to lives and homes; and I think most people would agree that this is the right approach,” he wrote.

“But this involves tricky issues of policy and priority: town or country, front rooms or farmland?

“Flood defences cost money”

“Flood defences cost money; and how much should the taxpayer be prepared to spend on different places, communities and livelihoods - in Somerset, Lincolnshire, Yorkshire, or East Anglia? There’s no bottomless purse, and we need to make difficult but sensible choices about where and what we try to protect,” says Smith’s article.

Funding for day to day flood risk management activities, including maintenance, has fallen and continues to fall in this parliament as the government shifts its focus and spending to new capital projects that can secure partial investment from private sector sources.

Ben Mitchell, a partner at engineering consultant Peter Brett Associates, said the Agency did careful analysis to decide where to spend its resources.

“If you spend £3M to dredge rivers, why are you throwing science out of the window just because of public pressure?” he asked.

“There are 40 homes flooded in Somerset. The Army is wondering what to do down there - are they being asked to buy someone a loaf of bread? It’s a knee-jerk reaction. It’s almost disgraceful.”

In Boston, 579 homes were affected by storms and a tidal surge in early December.

Two months on, the flood defence wall is still being repaired and many people are in temporary accommodation. The local council is still waiting for a response to its plea for extra government support (see box).

There is a feeling in the town that Boston has not received the same help as those on the Somerset Levels because of reduced media interest.
“The night Boston flooded, Nelson Mandela died,” said a spokesman for Boston Borough Council. “We have not had the sort of media coverage [that Somerset has].”

As well as chasing the government for funding to cover its clean-up operation, the council is seeking assurances from the Agency that its £99M barrier scheme will go ahead on schedule.

“The December flood has made us more determined there should be no slippage in that project,” said the spokesman. “It will give us protection from a one-in-300-year event and would have stopped most of the town centre flooding on 5 December.”

Small versus large schemes

But flooding specialist Wilsham Consulting director Stephen Gibson said the Environment Agency should prioritise small local schemes rather than large flagship projects.

“Everyone is aware of Somerset and before that Tewkesbury - these are the headline cases, but flooding happens all year round and all around the country,” he said.

“There are masses of villages and towns that have small-scale flooding and need small works. The benefits of those would massively surpass those of the big schemes the Agency is doing.”

Whichever way it turns, the government cannot escape criticism of its flood risk management policy.

While many are saying dredging the rivers in Somerset is an expensive gimmick, others believe it is not going far enough.

The Association of Drainage Authorities (ADA) has written to ministers asking for more funding for land drainage.

“In Somerset, the rivers are down to 50% of the capacity they had 20 or 30 years ago. They have not been dredged because they are not high up the Agency’s priority list,” said ADA chief executive Jean Venables, also an ICE past president.

“The government has to make a special case and recognise the limitation of cost:benefit analysis,” she added.

“It would cost £4M to dredge the Parrett and the Tone [rivers]. There is more maintenance that needs doing to rivers across England and Wales.”

The ICE said the government would need to amend the way it prioritises areas for flood risk management.

“As land use changes, the way we assess what land we protect will have to change,” said ICE expert water panel member Roland Grzybek.

“As time moves forward, the value of farming land will increase and damage to agriculture will become a big factor.”

Boston: 579 Homes flooded

Proposals for an around £100M scheme to build a Boston Barrier similar to the Thames Barrier have been delayed because the scheme promoter has sought advice from the Treasury on ways to minimise costs

The barrier is a smaller version of the Thames Barrier in London in the tidal River Haven and would protect over 15,000 residential properties and nearly 700 businesses.

The National Infrastructure Pipeline, published alongside last year’s Autumn Statement, projected that the scheme
would get underway in 2013 but the scheme is still at the planning stage.

The Pipeline document indicates that construction would be underway in earnest in 2016/17.

But a report submitted to Lincolnshire County Council Flood and Drainage Management Scrutiny Committee last July said that consultation with central government was likely to result in delays.

“Treasury involvement is likely to enable the project team to build on wider procurement experience and result in improved financial modelling, other sources of investment and support with procurement models to deliver cost savings at project and programme level,” says the report.

“The process is likely to result in delays in obtaining approval and potential delays to the project. The project team are currently working on confirming the extent of potential delays and looking at ways to reduce the impacts on delivering the project.”

December’s tidal surge flooded 579 homes in Boston in Lincolnshire and its surrounding area.

Environment Agency workers and contractors were forced to install temporary demountable flood defences to stem the tide after a 30m section of flood wall was damaged by the surge.

In total, 60m of temporary defences were needed to tie in to the existing wall. Waterproofing along its mid-section is intended limit seepage.

Other temporary repairs to damaged flood defences were required in the town.

Site workers installed steel piles to depths of 3m and placed 2,000t of stone to mend a 40m breach in a flood bank at Slippery Gowt.

Other works on the flood wall include water-proofing along its mid-section to reduce seepage and 1t sandbags placed along its southern end to give the damaged wall extra stability.

Agency flood risk partnership manager Ian Russell said the temporary repairs were designed to withstand high tides until permanent repairs could take place.

Somerset: 40 Homes flooded

Flooding on the Somerset Levels is the result of prolonged and persistent rainfall - more than twice the average for this time of year. Up to 40 properties and 65m2 of land have flooded.

However, flood defences have protected over 200m2 of land and 3,500 properties, including in the surrounding towns of Langport, Martock, Ilchester and Ham.

The Environment Agency said it was doing everything it could to pump water off the Somerset Levels as quickly as river and tide levels allow.

Teams have been working around the clock since Christmas and extra manpower and pumping equipment has been brought in from around the country.

Sixty-five pumps are now working around the clock. This is the single largest pumping operation ever undertaken in Somerset.

There have been widespread claims that the flooding has been worsened by a lack of dredging. But the Environment Agency refutes this. It said increased dredging of rivers on the Somerset Levels would not have prevented the recent widespread flooding because of the sheer volume of rainfall.

It added that where dredging increases river flows, it can also make flooding worse downstream.

Nationally, the Environment Agency spent £45M in the last financial year on improving rivers, including dredging and weed clearance.

In Somerset, de-silting work was last carried out on pinch points on the Parrett and Tone rivers in November.

The Agency said it will work with government, the local council, internal drainage boards and other partners on a long-term action-plan for tackling flood risk on the Somerset Moors and Levels.

But this is not simple. Around 635km2 of Somerset is below sea level and the recent widespread flooding of the Somerset Levels and Moors is just one in a long record of flood events. Historical records show that in 1919, 280km2 of the Levels and Moors were flooded.

Readers' comments (2)

  • An interesting mix of units! The Somerset report referring to sq m? or sq miles? Doesn't help with the understanding of the issues.

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  • Little has been said of the effect of 'environmental' policies that have been pursued during the last two decades that have deliberately limited maintenance on river channels, improved by earlier flood alleviation works, resulting in the marked reduction in their designed flood carrying capacity.

    David Hockin, FICE

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