Floodplain development – a legacy problem or a solution?

Date for the implementation of SuDS is delayed yet again – probably not to the good in terms of managing flooding (see article). Equally the knee jerk option of never building on flood plain does need calm reconsideration, says Ben Mitchell.

Ben Mitchell, Peter Brett Associates

We definitely have a legacy of inappropriate floodplain development, much of which is historic from a time when flood risk was not properly understood, it is also due to some more recent development which was not properly planned or designed and somehow slipped through the net of regulatory control administered by the planning authorities with advice from the Environment Agency.  This has resulted in misery and disruption for those who have been flooded and a financial burden on both the tax payer and the insurance industry.

While the risk of flooding is not to be taken lightly, it is important that we do not fear it.  Headlines, of the large print variety, will proclaim how we should not develop on floodplains and indeed politicians will leap on the band wagon of public anger and frustration. 

Events this last winter were a stark reminder of this legacy and of why politicians want to get involved…often without a proper understanding of the science and the financial justification basis of ‘cost/benefit’ analysis.

"While the risk of flooding is not to be taken lightly, it is important that we do not fear it." 

However, new and appropriate floodplain development should be part of the solution and not part of the problem.  The minimum design standards for defence of new such floodplain development are laid down in British Standards, planning policy and ABI guidance.  If we design to these standards then we are on the first step towards appropriate floodplain development; for the second step we need to be innovative in the provision of benefits to existing property at risk. 

The government’s current strategy for provision of flood defence is through the concept of partner funding…and I understand that potential partners are currently rather thin on the ground.  Property development is the most realistic partner funding vehicle available, ideally using the same process by which transport infrastructure (such as a bypass or relief road) is often funded by the developers whose land is unlocked for development through the subsequent provision of access.  If this process is deemed as acceptable for the provision of transport infrastructure then why not for provision of flood defence infrastructure?

The Houses of Parliament and 10 Downing Street are both in Flood Zone 3 so the principle of floodplain development has to be accepted; it is just a matter of designing out the risk and adding in the benefits.  There are many examples of where more recent strategic floodplain development has been properly designed and defended while also bringing forward improvements to flood protection for existing property at risk.

There are also examples where such appropriate floodplain development proposals have been thwarted through ill-considered interpretation of planning policy, politicians leaping on a local vote stimulating band wagon or regulatory authorities worried about setting a precedent which could then potentially be used by less scrupulous developers to justify other less appropriate floodplain development.

Flood risk practitioners need to be bold and robust in helping to seek opportunities for sustainable floodplain development which help address both our legacy of inappropriate such development and the future threat of climate change impacts. The regulatory authorities also need more encouragement to adopt a ‘can do’ attitude rather than the more common negative attitude to floodplain development presumably because they had read the aforementioned large print headlines.

Photo: This aerial photo shows the site of the proposed Lincolnshire Lakes development near Scunthorpe for up to 6,000 homes on a raised platform in the defended floodplain of the River Trent. The proposals include reinforcement of the existing River Trent flood defence bank upon which the existing local communities rely for flood protection.


Ben Mitchell is a partner with  Peter Brett Associates.