Floating an Idea: Prof Goes with the Flow to Protect Homes from Floods
The U.S. government is pushing homeowners in flood-prone areas to elevate their houses, sometimes by more than 10 feet. But that’s expensive and separates people from their neighbourhood. English has a simple idea that she says will allow Louisianans to keep their homes at ground level: Instead of fighting floods, go with the flow. Allow homes to float on the water.700
The professor designed a home that sits on top of big blocks of styrofoam. When the water rises, so does the house. The building is connected to four metal posts to keep it from floating away. “They work with the water instead of going against the water,” English says. “It doesn’t matter if it’s a four-foot flood or a 14-foot flood.”
The idea isn’t new. Residents of a rural hamlet on the Mississippi River have built buoyant homes for decades. Floating houses are also popular in the watery Netherlands.
English first heard about buoyant homes at a conference after Hurricane Katrina. In 2006, English, then at Louisiana State University, built a test home with some mechanical design students.
She now splits her time between UW’s School of Architecture in Cambridge and Louisiana, where she is trying to raise money to build a full-scale prototype.
She hopes to demonstrate to American authorities that buoyant houses should be eligible for flood insurance. The government has been reluctant to go along so far, English says. “When I started at this, people told me I was nuts,” she says. “The idea of a floating house is just too strange.”
But nothing less than the unique culture of New Orleans is at stake, she says. “A whole way of life … in New Orleans is being destroyed,” she says. “This is actually something for people to come back to and restart their lives as much as possible as they were before.”
University of Waterloo Faculty of Engineering Annual Report
Usually, houses in low-lying areas are raised to protect them from floods. But a house on stilts can be hard to live in, and stilts don’t always work. “Even if you do put the house on eight-foot stilts, you might have a 10-foot flood, Elizabeth notes.
Elizabeth has degrees in both architecture and civil engineering. She brought these backgrounds together to design a foundation with a lightweight steel frame for strength and coated Styrofoam for buoyancy. “The foundation is designed to go under an existing house,” says English. “It leaves the house looking the same. New Orleans has whole neighbourhoods of perfectly recoverable houses where this system could be used.”
Her prototype house is already up and floating. “We’ve basically got it worked out,” she says. “It just makes so much sense. Trying to fight floodwater is a losing battle. It’s better to work with it and let the floodwater keep your house up.”
Floating an Idea: Prof Goes with the Flow to Protect Homes from Floods
A Louisiana State University engineering professor made the rounds of congressional staff and Bush administration officials this week to push a system she says could protect many homes from the kind of disastrous flooding that occurred in Hurricane Katrina.
Elizabeth English, who is affiliated with the Louisiana State University Hurricane Center, hopes to borrow an idea from the Dutch, who use “buoyant foundations” in some flood-prone communities to reduce flood damage.
In effect, the system works like a floating dock. When flooding occurs, the house is lifted above the water by flotation blocks beneath the home. The house settles to ground level when the flooding recedes. The concept, she said, is designed especially for wood-frame homes, such as the shotguns common in New Orleans. It would not work, at least as now conceived, for brick or concrete slab homes.
English said she heard about the idea last year during a symposium with counterparts from the Netherlands.
“I thought this could work in New Orleans,” English said. “If the Dutch can do it, we should be able to do it in Louisiana.”
A less sophisticated version has been used for years along some waterways in South Louisiana, she said.
The concept is relatively simple.
The flotation blocks, made of expanded polystyrene, commonly known as Styrofoam, are held together by steel frames and attached to the underside of a house, according to a description of her proposal. Four vertical guidance poles are attached not far from the corners of the house.
When flooding occurs, the flotation blocks lift the house.
Collars are attached around the poles to ensure that the house doesn’t go anywhere but up when the water rises and down when it falls, English said. The homes would be strengthened with steel channels attached to the bottom beams to ensure they are strong enough to withstand being lifted and dropped.
Amphibious Architecture: A Strategy for Flood-Resilient Housing
As global climate change causes sea levels to rise and weather events to become more extreme, the occurrence of severe floods will become more common around the world. The large populations living in deltaic or riverine floodplain regions will be particularly severely affected, especially those living at the lowest levels of income.
There is increasing awareness worldwide that traditional flood-mitigation strategies that alter the environment and create concentrations of risk, such as levee- and dike-building, only increase the likelihood of catastrophic concentrations when eventual failure inevitably occurs. The greater the degree of artifical protection, and the confidence that builds in the communities living behind it, the more disastrous are the consequences when an unexpected failure occurs. New Orleans learned this lesson the hard way in 2005, when 80% of the city flooded due to numerous failures of the levee system in Hurricane Katrina’s aftermath.
Two Years After the Storm, The Devastated City is a Boomtown of Fresh Ideas for Rebirth
The Daily Green
But, as the Los Angeles Times makes clear, the Big Easy is also an incubator of exciting change. Authorities are certainly in no position to guarantee the protection of New Orleans from a future Category 5
hurricane. Particularly with many scientists warning that the frequency and severity of great storms is likely to increase with global warming, the danger is very real. But designers and engineers are rushing to the challenge with ideas to mitigate potential damage.
One of the most original schemes is being put forth by a Harvard-educated, Louisiana State University professor named Elizabeth English, who suggests retrofitting houses with Styrofoam foundations. If high waters roll in, the houses can float. An amateur inventor has envisioned a special flood wall for his French Quarter apartment. A San Francisco architectural firm has proposed lining New Orleans’ shores with giant “sponge combs” filled with baby diapers. They would expand when wet to block surging floodwaters.
None of these ideas have received widespread or government support to date, but they illustrate how the rebuilding of the Gulf Coast represents an historic opportunity to do things differently. Clearly, our built environment poses many challenges, from safety to susceptibility to natural disasters to the enormous environmental footprint. Our buildings use up more energy, and thus fossil fuels, than any other sector, including industry and transportation. That’s why so many are looking at New Orleans as a chance to shine, instead of going back to business as usual and old bad habits.
Environmental groups have ridden into town, touting the opportunity to try out the latest in affordable green housing, which will provide substantial energy and resource savings, save residents money on bills, and make for cleaner, safer living spaces. For instance, a wave of builders are repurposing salvageable materials from the destruction, which is a win-win in terms of reducing costs and cleaning up the enormous mess.
Brad Pitt is lending his star power to Global Green USA, which is working on an affordable green building project in New Orleans that will hopefully be able to generate all of its own energy. It will have solar roofs, recycled carpeting, cisterns to catch rainwater, and geothermal heat pumps. Funding support has been provided by the Home Depot Foundation.
Many innovators are hoping that good things can rise out of the devastation on the Gulf Coast.
Plan Would Make Homes in New Orleans Floatable
Professor Proposes Buoyant Foundations for New Orleans Homes
English, working with a team of senior mechanical engineering students, is devising a way to retrofit houses with a flotation system that will keep them above water in a flood. Similar devices are already in use along the banks of the Raccourci Old River right here in Louisiana and as far away as the Netherlands and southeast Asia.
But English’s ‘amphibious’ foundation system is unique. It is designed to be used for retrofitting existing houses, such as the ‘shotgun’ style homes that are so plentiful in New Orleans. The design will be engineered to satisfy new building codes. It avoids many of the disadvantages that come with the more traditional method of elevating a house by lifting it high above the ground.
‘There are so many issues, both obvious and not so apparent, that come with permanently elevating homes,’ said English. Among them are significant expense and increased risk of wind damage, and such social issues as lack of convenience and accessibility, the loss of neighborhood character and the appearance of the structure if it were to be raised on stilts.
A home equipped with a buoyant foundation will remain low to the ground unless a flood occurs, in which case the house will rise as high as necessary to stay dry. Special flexible utility lines
accommodate the change in elevation. Then, the house simply floats until the water recedes, with a vertical guidance system keeping it in place. And, when there is no flooding, the house looks
essentially the same as it did before being retrofitted with a buoyant foundation.
English’s team hopes to secure enough funding to develop and begin testing a prototype as early as December of this year. They’ve recently received a donation of $2,500 from Innovative Technologies Group, or ITG, from West Virginia, but they’re in need of approximately $150,000 to support the project through completion.