Tropical Storm Imelda, which hit southeastern Texas in mid-September and dropped more than 40 inches of rain in parts of the Houston-Galveston area, produced at least the fifth 500-year flood in the past five years. And only a few weeks earlier, Hurricane Dorian blasted the Bahamas with sustained, 200-mile-per-hour winds that wiped whole communities off the map.
“Buildings and communities need to be better prepared to deal with the effects of climate change because the destruction from these storms is terrible,” said Katharine Burgess, vice president of the Urban Land Institute’s (ULI) Urban Resilience Program.
“We aren’t just looking at how structures and cities can bounce back from major storms and events like hurricanes, but also how they can be more prepared for the long-term environmental changes that we will be facing,” she added.
Buildings and communities need to be better prepared to deal with the effects of climate change.
The goal of the ULI, a nonprofit education and research organization, is to help urban planners, developers and others face a future where dangerous weather is more frequent and worrisome. The ULI hosts conferences and has produced a number of reports such as “Scorched: Extreme Heat and Real Estate” and “Future Proofing Real Estate from Climate Risks.”
Five years ago, she said, the term resilience wasn’t well understood and was “still considered kind of wonky. Some were interested in it, but didn’t always understand what exactly it meant. Now, though, it’s front and center for a wide range of people, including investors, builders, homeowners and insurance companies.”
Developers and investors take notice
For their part, developers are slowly getting on board, said David Martin, president of the Miami-based developer, Terra Group.
“Local governments across South Florida have been studying solutions for protecting against climate change for years,” he wrote in a 2018 opinion piece in the Miami Herald. “But our real estate industry has historically been sidestepping the issue. That pattern of neglect must end now.
“Florida is among the most susceptible states in the United States, when it comes to sea-level rise, but we are not alone. Climate change is a global phenomenon and its effects are far-reaching, from stronger storms and forest fires, to hurricanes and heat waves. Like Miami, coastal cities such as New York and Boston are tackling geologic challenges and rising seas.”
Many developers have embraced resilient design.
While there is no single panacea for solving what he called the “climate-change conundrum,” he said part of the answer is summed up in three basic development principles his company is adopting: 1.) Moving density away from vulnerable areas; 2.) Bringing people closer to mass transit; and 3.) Embracing innovation and resilient building techniques.
Laura Craft, head of the global sustainability program at Chicago-based Heitman — a real estate investment firm with $44 billion in assets under management — said resilience is of growing importance to her company
“If we are investing in properties for five to 10 years and selling to other investors for five to 10 years, we need to consider climate risk as part of our underwriting,” said Craft, who has been in her post for three years. “So it’s a really big deal.”
In the past, the typical way to mitigate risk has been with insurance, which is a one-year policy. Only recently have computer models been available to help investment managers understand a project’s vulnerability over longer periods of time. She said many developers have embraced resilience, though others haven’t. They need to be aware of potential threats from flooding or wind or wildfire.
But Heitman doesn’t just accept developers’ assurances, she noted. It has hired a company called Four Twenty Seven, which screens and scores all of Heitman’s assets on a 0 to 100 scale, highlighting potential risks to which a property could be vulnerable.
“If the score goes above a certain threshold, we do further due diligence and bring on a third-party consultant to learn more about the risk,” she said. “We take it a step further and look not only at the development, but the infrastructure around it. And some projects have been rejected because of climate-change related risks.”
Burgess, who leads the ULI’s resilience program, got her start in urban planning and design after Hurricane Katrina hit New Orleans in 2005, causing billions of dollars in damage. She said the ULI has a long history of providing technical assistance and undertaking research relating to sustainability, climate change and bouncing back from natural disasters.
In 2014, after it received funding from the Kresge Foundation, the resilience program was created following Hurricane Sandy, which battered the northeast coast of the United States two years earlier, killed more than 200, and caused an estimated $70 billion in damage.
“I think because of the major storms we’ve seen over the past six years, such as hurricanes Harvey, Maria and Irma, there has been a tremendous increase in awareness by the real estate industry and among ULI members, recognizing the importance of resilience in dealing with climate change. It’s a really important topic that’s highly relevant to real estate and land use.”
She said many industry leaders are “getting out ahead by incorporating resilient design and development approaches into their work and incorporating more sophisticated analysis of climate risks in their real estate investment decision making.”
The ULI report, developingresilience.uli.org, highlights a number of resilient development projects that have seen a demonstrable return on investment due to its forward-thinking design.
The best practices we are seeing include the incorporation of green infrastructure.
“Some types of the best practices we are seeing include the incorporation of green infrastructure, the use of renewable and distributed energy, elevated buildings and mechanicals, cool surfaces and heat-prepared design,” she said.
“We’re also working with more and more cities that are interested in putting these concepts of resilience into their land-use regulations and zoning. They are introducing incentive programs, so it’s been a privilege to collaborate with cities that support the development of these concepts.”
Cities working with developers for resilient communities
Earlier this summer, the city of Houston released a draft of its Climate Action Plan to improve its resilience to climate hazards. Among other things, the plan calls for increasing the generation of renewable energy, greater investment in green infrastructure and expanding the use of alternative modes of transportation by making it easier for people to walk, ride their bikes and use public transit.
The city is working with the Houston Advanced Research Center (HARC), an independent, science-and-engineering-based organization focused on building a sustainable future.
When he announced the plan, Houston Mayor Sylvester Turner said “climate change is no longer a mirage on the horizon. It is very real and something we need to deal with every day. If we don’t move with a sense of urgency, our city will suffer, our businesses will suffer and our people will suffer.”
Mayor Turner said the plan will develop strategies that will “not only help minimize the city’s carbon footprint but can help save money and improve the quality of life of residents. Co-benefits associated with such action planning include decreased traffic and congestion, improved air quality, better access to parks and green spaces, and cost savings through energy efficiency projects.”
According to a report prepared for the ULI, the 11,400- acre Bridgeland master-planned community, about 25 miles northwest of downtown Houston, weathered major storms in recent years well because of its resilient design and use of miles of lakes and open space to handle flooding. Buildings in the development also are built on raised fill, a key component.
“These lakes form a storm-water system that exceeds local design requirements, and which has managed storm events much larger than those anticipated,” the report said.
The first big test of the development’s drainage network came with the Tax Day flood on April 15, 2016, when 15 inches of rain fell within 12 hours at Bridgeland’s western edge, according to the study. This was calculated as a 600- year event for this area and set new high-water records, both for rainfall and for the water level in Cypress Creek. Even though Josey Lake — actually a series of lakes — had not yet been completed at the time, no homes and only isolated thoroughfares flooded.
Remarkably, analysis (and aerial footage) after this flood showed that the storm-water system conveyed the local flows as designed in the development, which is owned by the Howard Hughes Corp., a Dallas-based developer of master-planned communities. The high-water marks after the flood occurred not from local runoff, but from Cypress Creek exceeding its banks and flowing into Bridgeland’s lakes.
In 2017, Hurricane Harvey brought a larger and more sustained rainfall, with 17 inches of rainfall over 24 hours, and 27 inches of rain in 48 hours.
At Bridgeland’s western edge, the two-day rainfall total was considered a 5,000-year event, the report said. Standing water filled many streets (as is expected during an event of this magnitude) and flowed onto many yards, but again, no homes took on water — validating the team’s design standard decision.
During and after each event, numerous homeowners expressed gratitude for the foresight in planning for flood resilience. ULI’s report noted that one resident wrote on Facebook, “It was worth paying $30,000 more to live here and not have my house flood.”
Resiliency important to developers
Heath Melton, a vice president in charge of residential development at several Houston-area Howard Hughes Corp. developments, said resilience is important to his company.
“As Bridgeland experiences accelerating growth, we continue to optimize the master plan with a constant focus on innovation and sustainability,” said Melton, who serves on several ULI committees. “We remain committed to providing the best lifestyle and engaging experiences for our residents and visitors.”
Terra Group’s Martin, whose integrated development company was launched in South Florida nearly two decades ago, said his firm is building what he called sustainable, design-oriented communities that use parks and green spaces as a way to deal with runoff from storms.
Miami created some of the first building codes in the country more than 100 years ago. And after Hurricane Andrew in 1992, which had sustained 165-mile-per-hour winds and caused more than $27 billion in damage, Miami-Dade County adopted the toughest wind-related codes in the nation.
“For me, the climate change story is about dealing with the effects and innovation, return on investment and financing resilience,” Martin said. “For us, it’s a question of creating a lot of incremental tax revenue with our developments. We have chief resilience officers at the county, city of Miami, and Miami Beach, for example, and their task is to allocate resources for infrastructure with metrics that looks 50 and 100 years out.”
Long-term viability means bringing people and commercial density to higher ground while reducing exposure in low-lying areas.
Martin said long-term viability means bringing people and commercial density to higher ground while reducing exposure in low-lying areas. That’s a departure from the decades-old development model in South Florida, which he said was based on extracting as much value as possible from environmentally sensitive areas, such as land adjacent to the Everglades.
At the same time, the public and private sectors must collaborate to ensure workforce and market-rate housing opportunities are available in high-lying zones, he added. Developers and local governments should improve access to transit by linking multiple forms of mobility with commercial and residential uses.
Terra Group is doing this now, in partnership with Miami Dade County, at its newest project in Coconut Grove. Grove Central will combine 330 market-rate and workforce apartment units, retail stores, and an improved Metrorail station that will connect with the Miami trolley system, county buses, and the Underline linear park.
Martin said the development will include a rooftop solar trellis to create the state’s first “microgrid” within an urban development — capable of powering the project in its entirety. In addition, rainwater will be used for irrigation and wastewater, and groundwater will be harvested to keep public spaces climate-controlled.
The project, which is set about 12-feet above sea level, will also feature porous building materials designed to stave off flooding during heavy rains.
In East Boston, the Lendlease — an international property and infrastructure group based in Australia — has incorporated future climate change scenarios into its Clippership Wharf development, said Nick Iselin, general manager of the project. The area is vulnerable to flooding during anything much above a normal high or storm surges, he added.
“We often build on waterfronts, particularly in postindustrial areas, and resilience is of utmost importance to us,” he said. “It is a big part of our overall sustainability strategy going forward. It adds to the cost, but it’s worth it.”
Iselin called Clippership Wharf the most-resilient-minded project on Boston Harbor because the company raised the ground plain up for the first level of occupied apartments and condos from six to eight feet above surrounding roadway networks — and 14 feet above high tides — as a way to deal with potential flooding. That’s about three-and-one-half feet more than any other builder in the area, he said.
In a related development, Boston Mayor Marty Walsh launched his “Resilient Boston Harbor” plan in 2018 that would protect the city from climate change flooding by elevating roads in low-lying areas by as much as seven feet, build seawalls, natural areas and add 67 acres of green space to the city’s 47-mile shoreline.
Iselin said his company was able to raise the land under the Clippership Wharf project — which is being built in a former warehouse area — because “we had a seven-acre site with enough area around our buildings to be able to transition with attractive site walls, ramps, stairs, plantings and berms to the sidewalks and harbor walk,” he said.
When finished, it will have 478 apartments and condos. And rather than have lawns and viewing areas, he said builders excavated behind the wall to create a “living shoreline,” that emerges and submerges with the tidal flow. The project also has a kayak launch and recreation programs.
“It’s a completely different take on how to create wave-dissipating features but also repatriate a shoreline with native species and plantings,” he said. “That’s been an interesting experiment as well.”