Water Has Power
Classic "shotgun" style house on Rampart Street, Faubourg Marigny neighborhood of New Orleans.
Photo: Infrogmation, Wikimedia Commons
The City of New Orleans, founded in 1718, has always had a deep dependency on its connection to the water. It is the port linking the Mississippi River trade to the Gulf of Mexico and beyond. In Louisiana’s colonial era, the land was developed as sugar cane plantations, with narrow tracts extending back from river frontage. At the start of the 19th century, the portions closer to the river were developed for residential use. On a modern map, these narrow tracts show in the shape and organization of the majority of the 17 Wards that divide New Orleans. One of the largest Wards, the 9th, was further subdivided by the dredging of the industrial canal in the 1920s.
Creation of canals, levees, flood walls and a pumping system has figured large in the development of the city. The reliance on this infrastructure has resulted in much of the populated area of the city lying approximately three metres below sea level. The reaction to all major storms, including 1965’s Hurricane Betsy, which caused more than 80 fatalities and $1.43 billion in damage, was to pass new laws and strengthen the flood works. In 2005, when Hurricane Katrina struck, New Orleans’ population had grown to approximately 480,000. That storm claimed over 1,800 lives, caused $161 billion in damage and reduced the population of the city by half.
Since then, “The Big Easy,” home of Cajun food, Mardi Gras and jazz, has greatly recovered. The population has rebounded to 393,000. But the fully integrated, mature neighbourhoods within the city, where shops, work places and residences were all in close proximity to one another, have not been so lucky. One of those portions of the city fabric, the 9th Ward, where a unique cultural identity had grown and developed, has been lost.
Many of the older homes were single-storey “shotgun houses,” which are usually only 12 feet (3.5 m) wide, with doors at each end, and rooms strung one behind the other. Typically only a foot or two above the ground, the houses were built with the front porch tight against the street, resulting in a strong interactive community identity, reflecting great diversity and inclusiveness. The houses had been multi-generational and as a result supportive of family members with disabilities.
Post-Katrina, homes, businesses, schools and supports are gone but the narrow lots remain, with frontages less than 30 feet (9 m). Consequently, the sparsely built storm recovery houses are also long and narrow, but are now raised on stilts. While this feature offers some flood protection (the neighbourhood is still far below sea level), it has destroyed much of the intimacy of the streets.
Levees and other flood control and prevention structures have been built over many years, but recent events have shown them to be inadequate. The Louisiana coastal wetlands continue to disappear at a rate of one football field per hour. Coastal residents have no option but to move – despite the deep connection they hold to the land they inhabit.
Image: Floathouses, Lake Geierswald,
Photo: Tarrakaner, Wikimedia Commons
There is an option to address some of the obstacles to maintaining existing homes within areas that are prone to flooding. Buoyant foundations, or amphibious architecture, works on a principle similar to an anchored houseboat or floating dock. There is a foundation and a steel frame that holds flotation blocks to the underside of the structure. The house remains low to the ground except during flooding, when it temporarily elevates to exactly the level required to stay above water. Porches, decks and other ground-level features are either built in a flood resistant manner or constructed to rise above the flood with the house. When the flood recedes, the house settles back on its foundation. The above-grade portions of a retrofitted house look essentially unchanged, with only the foundation and elements at grade being affected. Only a guide structure is required so the house holds steady above the foundation, enabling original traditional architecture to be preserved.
Such a system is much less costly than the permanent static elevation change of lifting a house. There are no expensive retrofit expenses to deal with, since the house is unchanged. The municipal water and sewer services are maintained, with only specific house connections adapted with breakaway features. The roofs of permanently elevated structures may be exposed to greater wind damage. But, since the house can float above the flood, the contents, sometimes the most precious memories, are saved.
Just as important, the original character, form and fabric of a neighbourhood remain intact. It is assumed that residents will evacuate to a safe location during the actual flood, but the intimacy of the house and the street continues. Floods are temporary events of short duration, and the communities that have survived these events and have strong resilience can pull together in the face of crisis.
A greater hurdle than the floods are the laws that are often put in place to demolish communities and evict residents: Move or lose your financial support. The economic argument for this measure seems to revolve around how much is required to maintain the house, without consideration for the strong cultural roots of communities. There are lasting hardships imposed on people that have been forced to abandon their homes, both financial and social. Adaptive flood risk reduction strategies such as buoyant foundations offer a solution that should be reviewed on a case-by-case basis, to offer options for reducing hazard vulnerability and maintaining communities, residences and heritage through long-term disaster resilience.
The problem of flooding is not unique to Louisiana. Large populations living in coastal areas and floodplains throughout the world are increasingly vulnerable. Here in Ontario, and in our First Nations Communities, many suffer from a similar losing proposition. In October, 2018, a floating research pavilion was installed on a stormwater retention pond at the University of Waterloo, in Ontario. With a particular focus on flood-prone Indigenous communities, the pavilion is intended to provide valuable information for retrofitting existing homes, and consequently preventing dislocation of entire communities.[1]
Information provided by Dr. Elizabeth English, University of Waterloo and the Buoyant Foundation Project has been used in the writing of this article.[2]
NOTES:
http://buoyantfoundation.org/nrc-research-pavilion
www.buoyantfoundation.org