By Roger K. Lewis
Saturday, September 17, 2005
"Design with Nature" is the title of a weighty book written in the 1960s by landscape architect Ian L. McHarg -- and it is also precisely what we have not done in the Gulf Coast region, as Hurricane Katrina tragically demonstrated.
Historically, humans have failed to design with nature on all continents by building settlements in deserts, near geological fault lines, on steep slopes and unstable soils, in flood plains and wetlands, on coastal lowlands and barrier islands, and in extreme climates or remote locations where resources are limited and infrastructure is hard to sustain.
When I first began teaching architecture at the University of Maryland, "Design with Nature" was among the texts we asked students to read, reminding them that the key word in the title was "with."
The environmental bible of its time, "Design with Nature" graphically described the form and interdependence of Earth's fundamental ecosystems -- climate, geology, topography, hydrology and botanical and zoological habitats. McHarg sets forth, often in moralistic terms, fundamental principles and analytical strategies for determining how and where humans should use land.
Design students weren't alone in studying McHarg's lessons. Heeding his advice, practicing planners and architects undertook more-rigorous environmental analysis of project sites before generating plans for development. They prepared drawings showing topographical constraints, seismic and soil characteristics, 50-year and 100-year flood plains, wetlands, natural drainage patterns, and distribution of vegetation.
Once armed with this information, the designer could intelligently map out parts of a site suited and not suited for development. This was not only an environmentally prudent methodology, but also an economically prudent one since disturbing and building on land unsuitable for development usually is much more costly.
McHarg's book appeared when public environmental awareness was just beginning to grow. It was also when governments at all levels began to require that project proposals include detailed environmental analysis. New laws and regulations were being adopted that prohibited building on land that clearly was environmentally unsuited for development.
For example, in Maryland it is generally illegal to build in flood plains or designated wetlands, to disturb steep slopes, to cut down trees and forests beyond approved construction limits or to destroy recognized wildlife habitats.
Today, applying environmental common sense and current environmental standards, the city of Las Vegas, parts of Los Angeles and many of Maryland's Eastern Shore and Atlantic beach communities wouldn't get built. Venice would be condemned, and most of Bangladesh would be declared uninhabitable.
The challenge is that many urbanized regions already exist in places at risk environmentally. Yet these are places, such as New Orleans, to which people are tightly bound by history, culture and tradition, by strong family roots, by high-stakes property and business ownership, and by economic activities and resources.
This is why levees surround New Orleans, not because they are environmentally or technologically rational, but because the alternative -- not creating this unique city astride the Mississippi River -- was never an option. New Orleans was designed against, not "with" nature. It is a manifestation of how human nature tries to compete with Mother Nature.
Designing with nature does not mean that technology should not be used to resist nature's forces or to overcome natural impediments. We can engineer structures to withstand hurricane-force winds, support buildings on unstable ground by driving piles to bedrock, or replenish urban reservoirs with water pumped from deep aquifers or distant watersheds.
But the more we use technology against nature, rather than designing with nature, the higher the economic and environmental costs. And most scientists agree that, no matter how sophisticated technologies become, there are physical limits on what the earth can provide.
Despite the material and human devastation experienced in the wake of Katrina, New Orleans will not be abandoned, yet it will never be the same, as Washington Post staff writer Joel Garreau speculated in last Sunday's Outlook section.
In that same section, Outlook assistant editor Frances Stead Sellers explained how the Netherlands, another place that has historically defied nature, has changed somewhat its philosophical course. With operable storm-surge barriers, repositioned dikes and diversified wetlands, the Dutch now allow the sea to have its way most of the time, although the country is still not immune to flooding.
What about those New Orleans levees? Should they be made higher and stronger so the next Category 4 or 5 storm can't destroy the city?
Given the cost, the pressing need for billions of dollars elsewhere on the Gulf Coast and the climatic probabilities, this is not an easy question to answer. One thing is certain: Ian McHarg would answer with a resounding "no!"
Roger K. Lewis is a practicing architect and a professor of architecture at the University of Maryland.