Quantcast
Popular
Downtown Houston surrounded by flooding and mist after Hurricane Harvey. Prairie Pictures / The Image Bank / Getty Images

Houston’s Tall Buildings and Concrete Sprawl Made Harvey’s Rain and Flooding Worse

The science is clear that in order to prevent more extreme weather events like hurricanes, we need to stop burning fossil fuels. Thursday, EcoWatch reported on a study that found major hurricanes in the past decade were made five to 10 percent wetter because of global warming, and another study last year calculated that the record rainfall that flooded Texas during Hurricane Harvey was made three times more likely due to climate change.


Now, a second study focusing on Hurricane Harvey that was published in Nature Wednesday pointed to another thing we can do to reduce the impact of these devastating storms: change the way we build cities.

Researchers at the University of Princeton and the University of Iowa used computer models and historical data to determine that urbanization in Houston made both the flooding and the record rainfall worse than it would have been in a rural area, a Princeton press release explained.

While this can help Houston make changes going forward, it also has major implications for other Southeast and Gulf cities facing the threat of wetter storms.

"Hurricane Harvey's impacts on Houston highlight hazards to coastal cities along the Gulf Coast and Eastern Seaboard of the United States," co-author and Princeton civil and environmental engineering professor James Smith said in the press release. "An unfortunate repeat performance from Hurricane Florence this year underscores the problems of extreme tropical cyclone rainfall in urban settings."

Houston has both grown up and out in recent years, and both of those had an impact on rainfall and flood risk. But how does that work exactly?

Flooding

Urbanization's impact on flooding is pretty common sense. More concrete streets and sidewalks means less water can be absorbed into the ground, leaving it to flood those streets instead.

Researchers compared yearly flood peaks with population growth, and also compared the contemporary results with flood peaks from the 1950s, when Houston was much less built up. Sure enough, as development increased, so did flood risk.

"Urbanization is generally associated with a significant reduction in storm-water infiltration," Director of Iowa's Hydroscience and Engineering research center (IIHR) Gabriele Villarini explained in the press release. "Houston has experienced one of the most impressive urban-development booms in U.S. history, and with growth comes an increase in impervious surfaces. This increase in urbanization, combined with the region's flat clay terrain, represents a very problematic mix, even with flood-mitigation measures in place."

Rainfall

The reason that urbanization increases rainfall is a little more complicated. Basically, the increased number and height of buildings creates something called "surface roughness" that increases friction and, therefore, rainfall when the storm winds blow over it.

"When Hurricane Harvey blew into Houston, it literally got snagged on the city's tall skyscrapers and towers," Villarini said. "The friction caused by high winds buffeting tall buildings created a drag effect that influenced air and heat movement and resulted in optimal conditions for precipitation."

Researchers used computer models to run the same storm over the same geographic area with Houston's current infrastructure and with open fields. They found that less rain fell and that rainfall patterns changed in the imaginary rural Houston, as this graphic shows.

Rainfall from Harvey in urban v. rural Houston@3rdrockhome

Now that the researchers have shown the impact current urban design has on storms, they hope that urban planners will use that information to reduce risk.

"For every new roadway poured and for every new high-rise erected, there is an increased risk for more adverse rainfall and flooding, and that's certainly something that city officials and residents should consider when they contemplate future growth," Villarini concluded.

Show Comments ()

EcoWatch Daily Newsletter

Sponsored
Energy
Mackinac Bridge from Straits of Mackinac. Gregory Varnum / Wikimedia Commons

Michigan Gov. Signs Bill to Keep Line 5 Pipeline Flowing

Michigan's outgoing Gov. Rick Snyder signed legislation on Wednesday that creates a new government authority to oversee a proposed oil tunnel in the Straits of Mackinac to effectively allow Canadian oil to keep flowing through the Great Lakes.

The controversial tunnel will encase a replacement segment for Enbridge Energy's aging Line 5 pipelines that run along the bottom of the Straits, a narrow waterway that connects Lakes Huron and Michigan.

Keep reading... Show less
Popular
The illegal La Pampa gold mine, seen here in 2017, has devastated the Peruvian Amazon and spread poisonous mercury. Planet Labs

Unprecedented New Map Unveils Illegal Mining Destroying Amazon

A first-of-its-kind map has unveiled widespread environmental damage and contamination of the Amazon rainforest caused by the rise illegal mining.

The survey, released Monday by the Amazon Socio-Environmental Geo-Referenced Information Project (RAISG), identifies at least 2,312 sites and 245 areas of prospecting or extraction of minerals such as gold, diamonds and coltan in six Amazonian countries—Bolivia, Brazil, Colombia, Ecuador, Peru and Venezuela. It also identified 30 rivers affected by mining and related activities.

Keep reading... Show less
Animals
Mako sharks killed at the South Jersey Shark Tournament in June 2017. Lewis Pugh

Shark Fishing Tournaments Devalue Ocean Wildlife and Harm Marine Conservation Efforts

By Rick Stafford

Just over three years ago, I was clinging to a rock in 20 meters of water, trying to stop the current from pulling me out to sea. I peered out into the gloom of the Pacific. Suddenly, three big dark shapes came into view, moving in a jerky, yet somehow smooth and majestic manner. I looked directly into the left eyes of hammerhead sharks as they swam past, maybe 10 meters from me. I could see the gill slits, the brown skin. But most of all, what struck me was just how big these animals are—far from the biggest sharks in the seas, but incredibly powerfully built and solid. These are truly magnificent creatures.

Keep reading... Show less
Politics
Sen. Joe Manchin and United Mine Workers of America President Cecil Roberts held a press conference on Oct. 3, 2017. Bill Clark / CQ Roll Call

Coal-Friendly Manchin Named Top Dem on Senate Energy Panel

After weeks of discord over the potential appointment, Sen. Joe Manchin, the pro-coal Democrat of West Virginia, was named the ranking member of the Senate Committee on Energy and Natural Resources, Sen. Chuck Schumer announced Tuesday.

Many Democrats and environmental groups were adamantly opposed to Manchin serving as the top Democrat on the committee that oversees policies on climate change, public lands and fossil fuel production.

Keep reading... Show less
Sponsored
Insights/Opinion
Hikers on the Mt. Hollywood Trail in Griffin Park, Calif. while a brush fire burned in the Angeles National Forest on Aug. 26, 2009. Mel Melcon / Los Angeles Times via Getty Images

Major Health Study Shows Benefits of Combating Climate Change

During the holiday season, people often drink toasts to health. There's something more we can do to ensure that we and others will enjoy good health now and into the future: combat climate change.

Keep reading... Show less
Energy
Employees of Rural Renewable Energy Alliance working together with students and faculty of Leech Lake Tribal Collage to construct solar panels, 2017. Ryan James White

A Tribe in Northern Minnesota Shows the Country How to Do Community Solar

By Susan Cosier

Last summer on a reservation in northern Minnesota, students from Leech Lake Tribal College earned their solar installation licenses while they dug, drilled and connected five photovoltaic arrays. The panels shine blue on the plain, reflecting the sky as they generate roughly 235 megawatts of electricity a year, enough to help 100 families pay their energy bills. This is community solar in action.

Keep reading... Show less
Sponsored
Energy
Arches National Park. Chris Dodds / Flickr / CC BY-SA 2.0

Trump Auctions Off 150,000 Acres of Public Lands for Fracking Near Utah National Parks

On Tuesday the Trump administration offered more than 150,000 acres of public lands for fossil-fuel extraction near some of Utah's most iconic landscapes, including Arches and Canyonlands national parks.

Keep reading... Show less
Climate
The Vanderford glacier in East Antarctica is one of four that is beginning to melt, according to NASA. Angela Wylie / Fairfax Media / Fairfax Media via Getty Images

Melting Discovered in East Antarctic Region Holding Ice 'Equivalent to Four Greenlands'

Ice sheets in Greenland and West Antarctica have been melting at alarming rates in recent years, but at least the glaciers of East Antarctica were believed to be relatively stable. Until now. National Aeronautics and Space Administration (NASA) scientists have discovered that glaciers covering one-eighth of Antarctica's eastern coast have lost ice in the past 10 years. If the region keeps melting, it has enough ice in its drainage basins to add 28 meters (approximately 92 feet) to global sea level rise, BBC News reported.

Keep reading... Show less
Sponsored

mail-copy

The best of EcoWatch, right in your inbox. Sign up for our email newsletter!