Author: Ida Gabrielsson
Posted on 26 February 2018
Photo by Tony Lam Hoang on Unsplash
A Water Window project honored at COP 23 as a Best Climate Practice.
The Buoyant Foundation Project (BFD), Development of Amphibious Homes for Marginalized and Vulnerable Populations led by architecture professor Dr. Elizabeth English of the University of Waterloo, Canada was honored as a Best Climate Practice. The honor was presented by the Initiative on Climate Change Policy and Governance (ICCG) at the 23rd Conference of Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCC) in Bonn, Germany.
The BFD project was one of 12 projects that received funding from the Global Resilience Partnership Water Window Challenge (Water Window) by Zurich Insurance Group and the Z Zurich Foundation in 2017.
The Water Window addresses resilience in flood prone communities. The objective of the challenge is to promote water resilience to a range of shocks and stresses by developing and testing novel solutions that address local contexts with dedicated public and private sector funding, to implement and scale the most promising solution in the Sahel, the Horn of Africa, and South and Southeast Asia. There are 11 scale and seed projects being supported under the challenge. Further details can be found here.
The idea of the BFD project is to adapt a model for low-cost amphibious houses that was tested in flood-prone areas of Louisiana, USA to the flood-prone areas of the Mekong Delta in Vietnam. Dr. English and her team will retrofit houses in the Delta with a contraption that allows the house to move vertically up and down with the help of guiding poles and floating rafters. The poles and rafters will allow the house to rise up and float on water when flooding occurs, creating flood resilient homes.
In Vietnam, the team hopes to teach villagers how to implement amphibious architecture into their existing stilted homes. In an interview with United Nations Radio, English said “it’s really a very simple system they (Vietnamese villagers) just don’t know about it or how to do it, but if we give them some examples and teach them how to do it, they can do it themselves.”
Congratulations to Dr. English and her team for the honor and for the innovative model to create flood resilience in poor, vulnerable communities.
What is Amphibious Architecture?
Amphibious architecture refers to an alternative flood mitigation strategy that allows an otherwise-ordinary structure to float on the surface of rising floodwater rather than succumb to inundation. An amphibious foundation retains a home’s connection to the ground by resting firmly on the earth under usual circumstances, yet it allows a house to float as high as necessary when flooding occurs. Amphibious foundations make homes resilient; resilient homes are the bases for resilient communities.
What is a Buoyant Foundation?
A buoyant foundation is a particular type of amphibious foundation that is specifically designed to be retrofitted to an existing house that is already slightly elevated off the ground and supported on short piers. The system consists of three basic elements: buoyancy blocks underneath the house that provide flotation, vertical guideposts that prevent the house from going anywhere except straight up and down, and a structural sub-frame that ties everything together. Utility lines have either self-sealing ‘breakaway’ connections or long, coiled ‘umbilical’ lines. Any house that can be elevated can be made amphibious.
Last June, not long after a catastrophic thunderstorm swept through southern Ontario, bringing a month’s worth of rain in just a few hours, a group of seventy-five architects, engineers, and policymakers from sixteen countries gathered in the city of Waterloo to discuss how humanity will cope with its waterlogged future. The timing of the conference was a fitting meteorological coincidence; in a world increasingly transformed by climate change, heavy rains and major floods are becoming more common, at least in some areas. In the summer of 2017 alone, Hurricane Harvey dumped more than fifty inches of rain over Texas, a monster monsoon season damaged more than eight hundred thousand homes in India, and flash floods and mudslides claimed at least five hundred lives in Sierra Leone. In the past two decades, the world’s ten worst floods have done more than a hundred and sixty-five billion dollars’ worth of damage and driven more than a billion people from their homes.
It was statistics like these that animated the experts who had assembled in Ontario for the International Conference on Amphibious Architecture, Design and Engineering, a three-day event organized by Elizabeth English, an associate professor at the University of Waterloo. Unlike traditional buildings, amphibious structures are not static; they respond to floods like ships to a rising tide, floating on the water’s surface. As one of English’s colleagues put it, “You can think of these buildings as little animals that have their feet wet and can then lift themselves up as needed.” Amphibiation may be an unconventional strategy, but it reflects a growing consensus that, at a time of climatic volatility, people can’t simply fight against water; they have to learn to live with it. “With amphibious construction, water becomes your friend,” English told me. “The water gets to do what the water wants to do. It’s not a confrontation with Mother Nature—it’s an acceptance of Mother Nature.”
English began her career focussed on an altogether different force of nature: wind. After earning degrees in architecture and engineering, she eventually landed at Louisiana State University’s Hurricane Center, where she studied the effects of wind loads on buildings and the aerodynamics of windborne debris. In August of 2005, Hurricane Katrina hit New Orleans, about seventy miles southeast of her home in Baton Rouge. The storm’s high-speed winds peeled roofs off of buildings and flung debris through windows, but it was the flooding that really shocked English. “Katrina was much more of a water event than a wind event,” she said. “I started looking at the implications of all the flood damage and the social disruption that it caused, and I became very, very angry about the cultural insensitivity of the solutions that were being proposed.”
In the aftermath of the storm, the federal government recommended that residents permanently elevate their houses, lifting them up onto raised foundations or stilts. But English worried that hoisting the city’s low-slung, shotgun-style houses into the air would ruin its sense of community, making it more difficult for residents to chat with neighbors and passersby. “People didn’t want to move up,” English said. “And it visually thoroughly destroyed the neighborhoods. There had to be a better way.”
She discovered that better way in another perpetually sodden locale—the Netherlands, where developers were building a cluster of amphibious homes in a flood-prone region along the Maas River. The houses sat on hollow concrete boxes attached to large steel pillars. During a flood, the boxes would function like the hull of a ship, providing buoyancy. As the waters rose, the buildings would rise, too, sliding up the pillars and floating on the water’s surface. When the waters receded, the houses would descend to their original positions.
It was an elegant solution, English thought, but not quite what she was looking for. Building a hollow foundation is a major construction project; English wanted to give New Orleanians an easy and inexpensive way to modify their existing homes. In 2006, she founded a nonprofit called the Buoyant Foundation Project and began working with a group of architecture and engineering students to devise a method for retrofitting local homes with amphibious foundations. A typical New Orleans shotgun house sits slightly above the ground, resting atop short piers; the researchers could, they thought, fasten a steel frame to the underside of a house and affix a set of foam buoyancy blocks. Then they could sink posts into the ground and attach them to the corners of the frame, allowing the house to rise up off the piers without floating down the street.
English and her students built a full-scale prototype of the system, and in the summer of 2007 they put it to the test. They borrowed some corral panels from the College of Agriculture and built a temporary flood tank around their model amphibious home, pumping in water straight from the Mississippi River. The tank filled with two, three, four feet of water, and the house began to rise. By the time they stopped pumping, it was hovering about a foot above the piers. “It was a religious experience when it lifted off,” English recalled.
The system was simple and cheap; it could be installed by two reasonably handy people without heavy equipment for between ten and forty dollars a square foot. It left a building’s appearance and structure almost unchanged, and it was more resilient than permanent elevation, which can cost two or three times as much and make a building more susceptible to wind damage. “This is not a one-size-fits-all solution,” English said, noting that the system would not provide adequate protection against high-speed waves. “But it’s an excellent solution for some circumstances.”
English became so enamored of the approach that she began to think beyond the bayou. In the past decade, she and her colleagues at the Buoyant Foundation Project have designed amphibious-housing prototypes for low-income, flood-threatened regions in Nicaragua and Jamaica. They have also consulted with indigenous communities in Canada and Louisiana. (English kept her house there after she moved from L.S.U. to Waterloo, in 2007.) Thanks in part to the project’s work, the gospel of amphibiation is spreading. Amphibious buildings are popping up everywhere from the U.K., where the firm Baca Architects recently built a buoyant, light-drenched three-bedroom home on an island in the Thames, to Bangladesh, where a master’s student designed a sustainable affordable-housing unit that relies on eight thousand empty plastic water bottles for buoyancy.
Still, amphibious structures remain more of an innovative curiosity than a bona-fide building trend. It probably doesn’t help that the premise is profoundly counterintuitive. When English first started telling people about her work, they laughed at her. “It seemed so outlandish,” she said. But the biggest hurdles, English told me, are more prosaic. In the United States, federal law requires most homeowners living in high-risk flood zones to purchase flood insurance, but buildings with amphibious foundations are not eligible for the subsidized policies offered by the National Flood Insurance Program. In one of English’s academic papers, she mentions the story of a developer who built an amphibious house in New Orleans, then found himself unable to acquire an N.F.I.P. policy; the building remained unsold until he replaced the amphibious foundation with a traditional one.
In 2007, after English began promoting her concept on the Buoyant Foundation Project Web site, an official at the Federal Emergency Management Agency, which administers the N.F.I.P., wrote to her. He urged her not to release more information about her design and suggested that communities that permitted the floatable foundations could “jeopardize” their “good standing” with the N.F.I.P. A decade later, FEMA continues to maintain that more research is needed. “Although amphibious-building technology is changing, these systems raise several engineering, floodplain-management, economic, and emergency-management concerns,” an agency spokesperson said in a statement. “A technology that relies on mechanical processes to provide flood protection is not equivalent to the same level of safe protection provided by permanent elevation.”
English isn’t giving up. A few months after the conference, she flew to Vietnam, where she is designing two new amphibious houses that are slated to be built in January. She also has a grant from the National Research Council of Canada to begin developing guidelines for amphibious construction that the government can include in its official building code. English and other experts say that opinions about amphibious architecture are beginning to shift, especially as climate change makes innovative building solutions more urgent. “Usually, after a conference presentation, I’ll have people coming up to me and saying, ‘I’ve never heard of this before, this is such a great idea, how can I do this in my community?’ ” English said. “People don’t laugh at me anymore.”