Tuesday, December 29, 2009

A portfolio of responses

As we prepare to cross that imaginary line from 2009 into 2010, here's a question worth reflection: What are YOU doing to reduce your vulnerability to flooding?

Long before New Orleans filled with water, back when the name "Katrina" was not associated with the ugly images of human despair and physical destruction, our cousins across the pond were worried about flooding.

No, not the Dutch. This time I'm talking about the Brits.

And they weren't just worrying--they have been continuously reassessing the threats and developing appropriate responses. I talked briefly about this in my presentation during the Rising Tide conference in 2007.

The British, you may or may not know, have been fighting coastal and river flooding for hundreds of years. Their signature project is the Thames Barrier, a set of gates which protects London from storm surges pushing up the river into the city of 7.5 million. The target level of protection is 0.1% (1-in-1,000 chance per year).

The Thames Barrier ranks as the second largest flood protection barrier in the world. London becomes more vulnerable to inundation each year because of sea level rise and the on-going tectonic tilting of the ancient island. The current project is expected to protect the city only until about the year 2030.

Studies are already underway to decide what to do to protect the city beyond 2030. An April 2004 report from the UK's Foresight study group lays out the problem and initiates the dialogue for finding the solution. Here are some of the thoughts from the "Future Flooding" report published more than a year before Hurricane Katrina:

"Flood defences protect not only people and private properties, but also vital amenities and public assets, including hospitals, the emergency services, schools, municipal buildings and the transport infrastructure. Disruption of these by flooding can have major knock-on effects for business and society."

We saw this in the spot shortages of gasoline and the spike in prices in the weeks after Katrina. We are still feeling this now as the New Orleans area labors with a limited support system of hospitals and schools.

"The human cost of flooding cannot be measured by statistics alone… There will be mental-health consequences. Besides the considerable stress of extensive damage, the threat of repeat flooding, coupled with the possible withdrawal of insurance cover can make properties unsaleable, and cause long-term depression in the victims."

How many of us can say, "Been there, done that"? The effects of flooding linger for years after the water has gone down.

"The socially disadvantaged will be hardest hit. The poor are less able to afford flooding insurance and less able to pay for expensive repairs. People who are ill or who have disabilities will be more vulnerable to the immediate hazard of a flood and to health risks due to polluted floodwaters."

In fact statistics show that the elderly join the poor in their vulnerability. The death rate of elderly was many times that of younger people trapped in the flood.

"Many of the drivers that could have the most impact are also the most uncertain. Some of this uncertainty relates to scientific understanding – for example, uncertainties in how to model the climate. However, other sources of uncertainty are inescapable – such as the extent to which the international community will succeed in reducing greenhouse-gas emissions. It is therefore important to develop policies that can cope with a wide range of possible futures, and which can respond flexibly to an evolving world."

Flexibility? Good luck. Neither the people nor government at any level seem to be ready to be flexible. Worse, the focus remains on the effects of hurricanes and their devastation. When are we going to address the causes and ways to prevent devastation?

"It will be important to manage the layout and functioning of our cities so they can adapt to future changes in rainfall patterns. Approaches such as the creation of new green corridors and the maintenance of existing undeveloped spaces (including brownfield) would provide ‘safety valves’ for the storage and passage of floodwaters when the drainage networks become overloaded. They could also bring substantial sustainability benefits relating to the aesthetic and amenity value of water in towns. However, such schemes might require the abandonment of parts of existing urban areas, with councils and other agencies buying up properties to create new open areas."

Anybody remember the Bring New Orleans Back plan? The City Council declared it DEAD ON ARRIVAL. The BNOB plan had the nerve to recommend selective rebuilding and rehabitation of the city, a perfectly logical, practical and effective way to deal with the situation. Which is why it was murdered on the steps of City Hall by a mob of politicians with daggers.

But the most compelling part of the report for me is the constant theme that there is no single solution. There is no one course of action that will mitigate all risks. In fact, there is no combination of actions that can mitigate all risks. And to make the task more difficult, some of the factors are clouded in uncertainty, so actions need to be scalable and there need to be contingency actions ready to implement if the need arises.

The authors of this report call for "a portfolio of responses."

What this means is simply that no single medicine will provide the cure. Just as a doctor might prescribe medicine, exercise and a change of diet for common ailments, we will need a multi-faceted program to keep our coastal areas healthy.

Levees, walls and gates are the obvious measures we can employ. They can provide a great deal of protection for smaller storms.

But it can't stop there.

We need to be thinking about multiple lines of levee defences with areas of storage in between. We need to be thinking about moving critical infrastructure out of harm's way. We need to be thinking about elevating homes and businesses that remain in harm's way. And we need to be planning a total evacuation when the "big one" comes calling.

We need a portfolio of responses.

As we enter the new year, this is certainly worth some thought. The levees and floodwalls are being redesigned and rebuilt to reduce our vulnerability to flooding. What is the State of Louisiana doing? What is the City of New Orleans doing?

What are YOU doing to reduce your vulnerability to flooding?

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