Flood and Flooding Planning

Flooding is the most common natural disaster worldwide and according to the Hadley Centre for Climate Prediction and Research, “man-made climate change is expected to intensify the water cycle, with consequent increased rainfall”  into the foreseeable future. 

Estimates from Save the Children charities show that more than 137 million people worldwide are currently suffering the effects of flooding with the most susceptible areas in poorer regions which lack the resources to enact appropriate preventative measures such as India, Indonesia, Sierra Leon and China.  But more affluent western nations are far from immune. 

As many as 350,000 people in Gloucestershire, UK alone were affected by flooding this summer and millions of pounds have been spent to control the situation.  Various studies and legislation have been enacted to help predict floods and prevent exacerbation of involved risk factors, but how prepared are we for what is yet to come?

Preventative Measures

The most obvious way to avoid increased flood damage is to restrict development within existing floodplains.  But this is not always possible and given that humans are naturally drawn to areas with water such as shorelines and river frontage, there is often a delicate balance to maintain between unavoidable expansion and overdevelopment.

Within the UK, the Environment Agency is attempting to confront this issue by asserting its influence on local governments.  Significant efforts are being shunted to educate decision makers with a view to ensuring climate change is now the primary consideration when assessing planning applications, preventing further development within floodplains and placing better controls on surface water run-off.

Similar systems are also being enforced by FEMA in the US through their regulatory floodway programme.  Neither of these regulatory measures is intended to completely prevent future development, but to ensure development of critical areas is undertaken with great care in order to reduce further flood risks.

Ultimately, the burden of flood planning and control lies within local communities.  FEMA states, “The community is responsible for prohibiting encroachments, including fill, new construction, and substantial improvements, within the floodway unless it has been demonstrated through hydrologic and hydraulic analyses that the proposed encroachment will not increase flood levels within the community.” 

But this approach leaves a large window for local and regional governments’ interpretation and subsequent application rules. 

In order to create a more homogenous system, adaptation of industry related risk analysis techniques, borrowed from aerospace, automotive and electronics are currently being evaluated for application to flood risk assessment processes. 

The aim is to help clarify an ambiguous decision making process and create a measurable framework for determining whether a development will have environmental impacts above set levels of acceptance. 

One example of this is the EU flood control area (FCA) manuals which are designed to establish best practice among European nations when assessing flood risk.  And with researchers projecting a 40% increase in flooding as a result of rising sea levels and climbing temperatures, disaster and emergency response plans will become ever more imperative.

For more information on the UK Environment Agency flood risk planning and assessment regulations, go to:  http://www.environment-agency.gov.uk/subjects/flood/?lang=_e

For information on US FEMA flood risk management, go to:  http://www.fema.gov/plan/prevent/floodplain/index.shtm