Reflect on 1 page about these two articles, and cite them in the second page.  Reflection about climate change.

12/23/2020 Can We Turn Down the Temperature on Urban Heat Islands? – Yale E360

https://e360.yale.edu/features/can-we-turn-down-the-temperature-on-urban-heat-islands 1/6

T

Yale Environment 360

Can We Turn Down the Temperature on Urban Heat Islands?
Using citizen science volunteers, researchers are more accurately measuring temperature differences between
city hot spots and their cooler surroundings. With heat waves intensifying , the results are now being used to

develop a range of innovative urban planning strategies.

BY JIM  MORRISON • SEPTEMBER  12 ,  2019

he volunteers fanned out across cities from Boston to Honolulu this summer, with

inexpensive thermal monitors resembling tiny periscopes attached to their vehicles to

collect data on street-level temperatures. Signs on their cars announcing “Science Project in

Progress” explained their plodding pace — no more than 30 miles-per-hour to capture the dramatic

temperature differences from tree-shaded parks to sun-baked parking lots to skyscraper-dominated

downtowns.

�e work of these citizen scientists is part of a new way of studying the urban heat island effect, with

volunteers mapping two dozen cities worldwide in recent years. Past studies of urban heat islands — in

which metropolitan areas experience significantly higher temperatures than their surroundings — have

relied on satellite data that measures the temperature reflected off rooftops and streets. But Vivek

Shandas, a professor of urban studies and planning at Portland State University in Oregon and a

researcher leading the project, says the urban heat island effect is more complicated and subtler than

satellite data indicates.

“�ere’s much more nuance within the city,” Shandas says. “What we’re finding is that there’s upwards

of 15- to 20-degree Fahrenheit differences within a city. In fact, a city could have the same temperature

reading in one area as its rural or forested counterpart.”

On-the-ground data clearly demonstrate a correlation between
lower-income neighborhoods and higher temperatures.

A Chicago resident struggles with triple-digit temperatures during a heat wave in 2012. AP PHOTO/M. SPENCER GREEN

https://e360.yale.edu/

https://e360.yale.edu/assets/site/_1500x1500_fit_center-center_80/AP_120706121098_ChicagoHeat2012_web

https://e360.yale.edu/authors/jim-morrison

http://blogs.discovermagazine.com/citizen-science-salon/2019/08/09/wicked-hot-boston-urban-heat-island-uhi-mapping/#.XXZOFGandAx

https://www.weathernationtv.com/news/citizen-scientists-take-to-the-streets-to-map-the-hottest-places-in-ten-u-s-cities/

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ALSO ON YALE E360

From high above, a new way of seeing our

urban planet. Read more.

By understanding in detail where hot spots are located, cities can address extreme heat neighborhood-

by-neighborhood, choosing from a variety of strategies that include removing or whitewashing black

asphalt or roof surfaces, adding more trees for shade, requiring developers to vary the heights of new

buildings to increase airflow, and opening more public air-conditioned spaces.

Using Shandas’ research, Portland, the first city Shandas and his team surveyed, has proposed zoning

code amendments and strategies targeting urban heat, including limiting paved neighborhood

parking areas and increasing space for trees. In addition, city officials said that Shandas’ on-the-ground

data clearly demonstrated a correlation between lower-income neighborhoods and higher

temperatures. Shandas’ work also showed that the places where lower-income people often work, such

as the industrial areas along Portland’s rivers, also experience higher-than-average temperatures, the

officials said.

Other urban heat island studies have shown that the hottest places in metropolitan areas are often in

poor, minority neighborhoods with few trees, and this research can provide a framework for city

planners to address the problem.

Shandas and his teams have mapped 24 cities in

the United States and worldwide, including

Albuquerque; parts of the Vancouver

metropolitan area; Hong Kong; Doha, Qatar; and

Hermosillo, Mexico. In the past, urban heat

island studies relied on data from satellites or

stationary sensors, but Shandas’ appears to be

the first enlisting citizen scientists to collect

temperature data using mobile sensors.

Researchers have studied urban heat island

effects in every major country from Australia,

where a government study warned that heat

wave deaths would quadruple by 2050, to China,

which has more than 40 cities with populations

exceeding 2 million people. Globally, heat is the

number one weather-related killer, causing more

deaths each year than floods, tornadoes, or hurricanes. Extreme heat can kill directly via heat stroke

and indirectly through increased risk of heart attack and stroke. Climate models show that in some

cities the number of high-heat days could double by 2040.

�is summer’s heat wave in Europe, with temperatures soaring to a record-breaking 46 degrees Celsius

(115 degrees F) in the south of France, killed 1,500 people in France alone, the French health minister

said this week. Russian officials reported that a 2010 heat wave killed 11,000 people in Moscow. �e rise

in overall global temperature makes extreme heat events, including consecutive days of high heat,

more likely. Mitigating extreme heat, one recent study says, would save lives.

Urban heat islands have been generally understood since large cities began to emerge

in the 19th century, but research by Shandas and others reveals a complicated

patchwork of hot spots and cool spots that change during the course of a day and are

determined by urban design. Satellite data, for instance, showed midtown Manhattan

to be an afternoon hot spot. But mapping unveiled a different picture.

“When you actually go down to the ground, where people are walking and life is

happening, it turns out it’s not the same signal,” Shandas says.

“Ultimately, we’re trying to adapt the landscape to respond to
the increasing frequency and intensity of heat waves,” says one

Researcher Vivek Shandas has mapped street-level temperatures in 24 cities worldwide.

COURTESY OF PORTLAND STATE UNIVERSITY

https://e360.yale.edu/assets/site/_1500x1500_fit_center-center_80/VivekShadas_web

https://e360.yale.edu/features/from-high-above-a-new-way-of-seeing-our-urban-planet

https://e360.yale.edu/features/urban-heat-can-white-roofs-help-cool-the-worlds-warming-cities

https://www.sciencedirect.com/science/article/pii/S221067071630066X

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5923682/

https://www.portlandoregon.gov/bps/article/645259

https://www.mdpi.com/2073-4433/10/5/282/htm

https://www.mdpi.com/1660-4601/15/4/640/htm

https://www.epa.gov/sites/production/files/2014-07/documents/epa_how_to_measure_a_uhi

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5751017/

https://www.sciencedirect.com/science/article/pii/S2212095518300555

https://www.smh.com.au/environment/climate-change/heatwave-deaths-to-quadruple-government-report-finds-20130730-2qxef.html

https://www.nature.com/articles/s41598-017-09628-w

https://www.weather.gov/hazstat/

https://www.niehs.nih.gov/research/programs/geh/climatechange/health_impacts/cardiovascular_diseases/index.cfm

https://www.who.int/news-room/fact-sheets/detail/climate-change-and-health

https://iopscience.iop.org/article/10.1088/2515-7620/ab27cf

https://www.theguardian.com/world/2019/sep/09/summer-heatwaves-in-france-killed-1500-says-health-minister

https://www.abc.net.au/news/2010-09-18/russian-heatwave-killed-11000-people/2265184

https://www.climatecentral.org/news/extreme-heat-climate-change-19641

https://advances.sciencemag.org/content/5/6/eaau4373

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expert.

�e long shadows of Manhattan skyscrapers, for example, can make parts of that borough cooler in

summer than some neighborhoods in Queens, which generally has low-rise buildings. On the other

hand, midtown Manhattan retains heat and starts the day much warmer because the heat that’s

absorbed by buildings, roofs, streets, and sidewalks during the day doesn’t dissipate as well at night.

“It’s the built environment that we’re really trying to understand because, ultimately, we’re trying to

adapt the landscape to respond to this increasing frequency, intensity, and duration of heat wave,”

Shandas says. “We’re trying to get more precise data. And there were so many surprises.” A large

expanse of water, for instance, or grass that is not watered, can be almost as hot as concrete, he says.

Jaime Madrigano, a researcher with the RAND Corporation who has studied urban heat, praised the

way Shandas and his colleagues were using citizen science volunteers and “getting the community

engaged in the issues around extreme heat… I think there are a lot of cities that are trying to make

these changes. �is kind of data is really important to doing that.”

Shandas grew up in Bangalore, and during visits there and to other cities in India he began thinking

about how cities have developed without regard for the increasing incidence of extreme weather

events linked to climate change, including heat waves. He began his research with a bit of engineering,

using a National Science Foundation grant to reach out to engineers who helped create the hand-made

instrumentation that transmits data. With funding from the U.S. National Oceanic and Atmospheric

Administration, he first mapped Portland in 2015.

A breakfast in Portland the next year with Jeremy

Hoffman, who had just accepted a job as the

climate and earth scientist at the Science

Museum of Virginia, led to a partnership and

citizen-science projects mapping Richmond,

Baltimore, and Washington, D.C.

�ose partnerships with local groups have been

invaluable, says Hoffman. “It was really useful to

have the local perspective” while creating the

mapping routes, Hoffman says. “Where is the

park that everybody goes to? Where are they

going to redevelop over the next couple of years?

�at kind of knowledge made our campaigns not

only scientifically useful, but publicly attractive.

It was the people themselves getting involved; it

wasn’t just the scientists.”

�e studies correlated data to the tenth of a

degree from sensors on vehicles that followed a

series of one-hour, zigzag routes — early morning,

mid-afternoon, and early evening — driven by

volunteers recruited by local science museums, universities, and non-profits. Fifteen teams mapped

Richmond during a summer weekend in 2017. One park along the James River measured 87 degrees F,

while a few miles away, along a four-lane roadway, it was 103 degrees.

Shandas and Hoffman say their work demonstrates that extreme heat is a social justice issue. In

Richmond’s hottest areas, they found a higher concentration of poverty and of 911 calls for heat-related

illnesses. Mapping last year in Washington, D.C. and Baltimore found a similar correlation, with

higher temperatures in lower-income neighborhoods largely barren of trees and lower temperatures in

more affluent, tree-shaded areas. Shandas and Hoffman recently completed a paper, due to be

published soon, comparing redlined neighborhoods — those once illegally designated by lenders as

A mobile sensor collects temperature data in suburban Sacramento this summer. COURTESY OF

VIVEK SHANDAS

https://e360.yale.edu/assets/site/_1500x1500_fit_center-center_80/ElkGrove1_web2

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4492264/

https://www.mdpi.com/2225-1154/5/2/41/htm

https://toolkit.climate.gov/case-studies/where-do-we-need-shade-mapping-urban-heat-islands-richmond-virginia

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too risky to make home loans — with extreme urban temperatures. “�e big take-home point for the

paper is that 92 percent of the cities that were redlined are now warmer than their A-rated neighbors,”

Hoffman says. “�is seems like it’s predominantly due to a lack of green and a dominance of gray.”

Shandas says the research has uncovered six things that affect urban heat. �ree are living — the

volume of the tree canopy, the height of the tree canopy, and the ground level vegetation. �ree are

human-built — the volume of buildings, the difference in building heights, and the coloring of the

buildings.

The differences in morning and afternoon temperatures in Richmond, Virginia. COURTESY OF JEREMY

HOFFMAN

Poverty levels in Richmond. Lower-income neighborhoods often experience the worst heat in the city. COURTESY OF JEREMY

HOFFMAN

https://e360.yale.edu/assets/site/_1500x1500_fit_center-center_80/Urban-heat_Richmond_web

https://e360.yale.edu/assets/site/_1500x1500_fit_center-center_80/poverty_Richmond_web

https://www.mdpi.com/2073-4433/10/5/282/htm

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ALSO ON YALE E360

Energy Equity: Bringing solar power to low-

income communities. Read more.

�ere were some surprises, he says. �e volume of buildings can have both a negative and positive

effect. Tall buildings that cast shade lower relative afternoon temperatures, while a large volume of

shorter buildings, like the big-box stores in suburban areas, help generate hotter afternoon

temperatures. Ground-level vegetation doesn’t necessarily reduce temperature — it’s not that much

cooler than asphalt — unless it’s watered. Shandas also has found that increasing the difference in

building heights in an area creates more air circulation, which has a cooling effect.

Creating cooler cities doesn’t necessarily mean building at lower densities. What matters, he says, is

varying building heights, the canopy cover, and street widths. “It wasn’t about no buildings and all

green,” he says. “It was about designing our spaces more thoughtfully.”

Some cities are already using the detailed research to guide decisions. In Richmond, a heat map and a

vulnerability map showing those more at risk appear in reports for housing, transportation, and the

climate action plan, and the city’s comprehensive master plan calls for reducing urban heat.

Richmond hasn’t invested in planting trees yet, he adds, but citizen-science groups like Groundwork

RVA and the museum have developed programs such as �rowing Shade in RVA, a program teaching

students about urban heat that has led to them planting peach trees at local high schools and

designing shady structures for neighborhood bus stops.

Some of the deadliest heat waves in recent decades have taken
place in northern cities, where people are not accustomed to

extreme heat.

Groundwork RVA’s parent organization, Groundwork USA, has funding to expand on this work for a

Climate Safe Neighborhoods project exploring the relationship between historical race-based housing

segregation and the impacts of climate change in Denver, Colorado; Elizabeth, New Jersey; Richmond,

California; and Pawtucket, Rhode Island.

Even at higher latitudes, heat is an issue. According to the Centers for Disease Control, some of the

deadliest heat waves in recent decades have taken place in northern cities like Chicago, where people

are not accustomed to extreme heat and more residences lack air conditioning. A five-day heat wave in

Chicago in 1995 led to the deaths of 739 people.

In Portland, Shandas has created heat maps containing demographic information including age, race,

education, poverty level, and education. �e city is focusing its efforts in areas where urban heat

islands and indicators of vulnerability, including low-income levels, overlap. Shandas’ work is reflected

in Portland’s Better Housing by Design zoning update, in which the city has proposed zoning

amendments to reduce urban heat island effects, including limiting surface parking areas in

residential neighborhoods and requiring landscaped setbacks between buildings and streets to

provide more space for trees.

His next step is to expand heat island mapping to 50 cities in 2020. �e key question,

he says, is whether cities will begin making the changes necessary to decrease deaths

from extreme heat.

“�ose are very preventable deaths,” Shandas says. “We can identify those locations

and ameliorate some of the effects. It ultimately comes down to how to help these

people. We have the technology.

Jim Morrison writes about the environment, travel, the arts, and business. His stories have appeared in Smithsonian, �e New York
Times, �e Wall Street Journal, National Wildlife, Pacific Standard, �e Washington Post, and numerous other publications. He lives
in Norfolk, Virginia.  MORE →

https://e360.yale.edu/features/energy-equity-bringing-solar-power-to-low-income-communities

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Richmond teens design shade projects

Home

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https://www.cdc.gov/climateandhealth/pubs/extreme-heat-guidebook

http://www.capainsights.com/social-vulnerability

https://www.portlandoregon.gov/bps/article/683878

https://e360.yale.edu/authors/jim-morrison

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12/16/2020 Houston’s Flood Is a Design Problem – The Atlantic

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RICHARD CARSON / REUTERS

Floods cause greater property damage and more deaths than tornadoes or hurricanes.

And Houston’s �ood is truly a disaster of biblical proportions: e sky unloaded 9

trillion gallons of water on the city within two days, and much more might fall before

Harvey dissipates, producing as much as 60 inches of rain.

Pictures of Harvey’s runoff are harrowing, with interstates turned to sturdy and mature

rivers. From Katrina to Sandy, Rita to Tōhoku, it’s easier to imagine the �ooding caused

by storm surges wrought by hurricanes and tsunamis. In these cases, the �ooding

problem appears to be caused by water breaching shores, seawalls, or levees. ose

examples reinforce the idea that �ooding is a problem of keeping water out—either

through fortunate avoidance or engineering foresight.

But the impact of �ooding, particularly in densely developed areas like cities, is far more

constant than a massive, natural disaster like Harvey exposes. e reason cities �ood

T E C H N O L O GY

Houston’s Flood Is a Design Problem
It’s not because the water comes in. It’s because it is forced to leave
again.

I A N B O G O S T AU G U S T 2 8 , 2 0 1 7

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https://en.wikipedia.org/wiki/2011_T%C5%8Dhoku_earthquake_and_tsunami

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isn’t because the water comes in, not exactly. It’s because the pavement of civilization

forces the water to get back out again.

* * *

ere are different kinds of �oods. ere’s the storm surge from hurricanes, the runoff

from snowmelt, the inundation of riverbanks. But all these examples cast �ooding as an

occasional foe out to damage human civilization. In truth, �ooding happens constantly,

in small and large quantities, every time precipitation falls to earth. People just don’t

tend to notice it until it reaches the proportions of disaster.

R E C O M M E N D E D R E A D I N G

Under normal circumstances, rain or snowfall soaks back into the earth after falling. It

gets absorbed by grasslands, by parks, by residential lawns, by anywhere the soil is

exposed. Two factors can impede that absorption. One is large quantities of rain in a

short period of time. e ground becomes inundated, and the water spreads out in

accordance with the topography. e second is covering over the ground so it cannot

soak up water in the �rst place. And that’s exactly what cities do—they transform the

land into developed civilization.

Roads, parking lots, sidewalks, and other pavements, along with asphalt, concrete,

brick, stone, and other building materials, combine to create impervious surfaces that

resist the natural absorption of water. In most of the United States, about 75 percent of

its land area, less than 1 percent of the land is hardscape. In cities, up to 40 percent is

impervious.

e natural system is very good at accepting rainfall. But when water hits pavement, it

creates runoff immediately. at water has to go somewhere. So it �ows wherever the

Facebook Is a Doomsday Machine

A D R I E N N E L A F R A N C E

Dressed for the Plague. No, Not is One.

K A I T LY N T I F FA N Y

A person
dressed in a
17th-
century
plague

e Secret Internet of TERFs

K A I T LY N T I F FA N Y

A series
of browser
tabs, with
flames in
the center

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grade takes it. To account for that runoff, people engineer systems to move the water

away from where it is originally deposited, or to house it in situ, or even to reuse it. is

process—the policy, planning, engineering, implementation, and maintenance of urban

water systems—is called stormwater management.

According to my Georgia Institute of Technology colleague Bruce Stiftel, who is chair

of the school of city and regional planning and an expert in environmental and water

policy governance, stormwater management usually entails channeling water away from

impervious surfaces and the structures built atop them. In other words, cities are built

on the assumption that the water that would have been absorbed back into the land

they occupy can be transported away instead.

Like bridges or skyscrapers designed to bear certain loads, stormwater management

systems are conceived within the limits of expected behavior—such as rainfall or

riverbank overrun events that might happen every 10 or 25 years. When these intervals

are exceeded, and the infrastructure can’t handle the rate and volume of water, �ooding

is the result.

Houston poses both a typical and an unusual situation for stormwater management.

e city is enormous, stretching out over 600 square miles. It’s an epitome of the urban

sprawl characterized by American exurbanism, where available land made development

easy at the edges. Unlike New Orleans, Houston is well above sea level, so �ooding risk

from storm surge inundation is low. Instead, it’s rainfall that poses the biggest threat.

A series of slow-moving rivers, called bayous, provide natural drainage for the area. To

account for the certainty of �ooding, Houston has built drainage channels, sewers,

outfalls, on- and off-road ditches, and detention ponds to hold or move water away

from local areas. When they �ll, the roadways provide overrun. e dramatic images

from Houston that show wide, interstate freeways transformed into rivers look like the

cause of the disaster, but they are also its solution, if not an ideal one. is is also why

evacuating Houston, a metropolitan area of 6.5 million people, would have been a

terrible idea. is is a city run by cars, and sending its residents to sit in gridlock on the

thoroughfares and freeways designed to become rivers during �ooding would have

doomed them to death by water.

* * *

Accounting for a 100-year, 500-year, or “million-year” �ood, as some are calling

Harvey’s aftermath, is difficult and costly. Stiftel con�rms that it’s almost impossible to

design for these “maximal probable �ood events,” as planners call them. Instead, the

hope is to design communities such that when they �ood, they can withstand the ill

effects and support effective evacuations to keep people safe. “e Houston event seems

like an illustration that we haven’t �gured it out,” Stiftel says.

https://www.publicworks.houstontx.gov/sites/default/files/all_swat_projects%20_rev_council_district_web_version

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Many planners contend that impervious surface itself is the problem. e more of it

there is, the less absorption takes place and the more runoff has to be managed.

Reducing development, then, is one of the best ways to manage urban �ooding. e

problem is, urban development hasn’t slowed in the last half-century. Cities have only

become more desirable, spreading outward over the plentiful land available in the

United States.

e National Flood Insurance Program, established in 1968, offered one attempt at a

compromise. It was meant to protect and indemnify people without creating economic

catastrophe. Instead of avoiding the �oodplain, insurance allowed people to build

within it, within management constraints recommended by FEMA. In theory, �ood-

hazard mitigation hoped to direct development away from �ood-prone areas through

the disincentives of risk insurance and regulatory complexity.

Since then, attitudes have changed. For one part, initial avoidance of �oodplains created

desirable targets for development, especially in the middle of cities. But for another,

Stiftel tells me that attitudes about development in �oodplains have changed, too. “It’s

more about living with water than it is about discouraging development in areas prone

to risk.”

Sometimes “living with water” means sidestepping the consequences. Developers

working in �ood zones might not care what happens after they sell a property. at’s

where governmental oversight is supposed to take over. Some are more strict than

others. After the global �nancial crisis of 2008, for example, degraded local economies

sometimes spurred relaxed land-use policy in exchange for new tax bases, particularly

commercial ones.

In other cases, �oodplains have been managed through redevelopment that reduces

impervious surfaces. Natural ground cover, permeable or semi-permeable pavers, and

vegetation that supports the movement of water offer examples. ese efforts dovetail

with urban redevelopment efforts that privilege mixed-use and green space, associated

with both new urbanism and gentri�cation. Recreation lands, conservation lands and

easements, dry washes, and other approaches attempt to counterbalance pavement

when possible. Stiftel cites China’s “sponge cities” as a dramatic example—a

government-funded effort to engineer new, permeable materials to anticipate and

mitigate the �ooding common to that nation.

* * *

But omas Debo, an emeritus professor of city planning at Georgia Tech who also

wrote a popular textbook on stormwater management, takes issue with pavement

reduction as a viable cure for urban �ooding. “We focus too much on impervious

surface and not enough on the conveyance of water,” he tells me. Even when reduced in

quantity, the water still ends up in in pipes and concrete channels, speeding fast toward

https://www.theguardian.com/public-leaders-network/2016/oct/03/china-government-solve-urban-planning-flooding-sponge-cities

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larger channels. “It’s like taking an aspirin to cure an ailment,” he scoffs. Houston’s

�ooding demonstrates the impact.

Instead, Debo advocates that urban design mimic rural hydrology as much as possible.

Reducing impervious surface and improving water conveyance has a role to play, but

the most important step in sparing cities from �ooding is to reduce the velocity of water

when it is channelized, so that it doesn’t deluge other sites. And then to stop moving

water away from buildings and structures entirely, and to start �nding new uses for it in

place.

at can be done by collecting water into cisterns for processing and reuse—in some

cases, Debo explains, the result can even save money by reducing the need to rely on

utility-provided water. Adding vegetation, reclaiming stormwater, and building local

conveyance systems for delivery of this water offer more promising solutions.

ough retired from Georgia Tech, Debo still consults on the campus’s local

stormwater management efforts. In one case, the institute took a soccer �eld and made

it into an in�ltration basin. Water permeates the �eld, where it is channeled into pipes

and then into local cisterns.

In Houston’s case, catastrophic �oods have been anticipated for some time. e

combination of climate change, which produces more intense and unpredictable

storms, and aggressive development made an event like this week’s almost inevitable.

e Association of State Floodplain Managers has called for a national flood risk-

management strategy, and the Houston Chronicle has called �ood control the city’s

“most pressing infrastructure need.” A lack of funding is often blamed, and relaxed

FEMA regulations under the Trump Administration won’t help either.

But for Debo and others, waiting for a holistic, centralized approach to stormwater

management is a pipe dream anyway. Just as limiting impervious surface is not the

solution to urban stormwater management, so government-run, singular infrastructure

might not be either. “It’s much more difficult, and a much bigger picture,” Debo insists

to me. “ere is no silver bullet for stormwater management.”

* * *

One problem is that people care about �ooding, because it’s dramatic and catastrophic.

ey don’t care about stormwater management, which is where the real issue lies. Even

if it takes weeks or months, after Harvey subsides, public interest will decay too. Debo

notes that traffic policy is an easier urban planning problem for ordinary folk, because it

happens every day.

So does stormwater—it just isn’t treated that way. Instead of looking for holistic

answers, site-speci�c ones must be pursued instead. Rather than putting a straight

https://www.theguardian.com/environment/2017/jun/16/texas-flooding-houston-climate-change-disaster

https://www.texastribune.org/boomtown-floodtown/

https://www.floods.org/ace-files/documentlibrary/Publications/ASCE_Call_for_National_Flood_Risk_Management_Strategy

http://www.ttnews.com/articles/texas-officials-drafting-wish-list-potential-infrastructure-funding-windfall

https://www.nytimes.com/2017/08/17/nyregion/trump-hurricane-sandy-floods.html

12/16/2020 Houston’s Flood Is a Design Problem – The Atlantic

https://www.theatlantic.com/technology/archive/2017/08/why-cities-flood/538251/ 6/6

channel through a subdivision, for example, Debo suggests designing one to meander

through it, to decrease the velocity of the water as it exits.

e hardest part of managing urban �ooding is reconciling it with Americans’

insistence that they can and should be able to live, work, and play anywhere.

Waterborne transit was a key driver of urban development, and it’s inevitable that cities

have grown where �ooding is prevalent. But there are some regions that just shouldn’t

become cities. “Parts of Houston in the �oodway, parts of New Orleans submerged

during Katrina, parts of Florida—these places never should have been developed in the

�rst place,” Debo concludes. Add sea-level rise and climate-change superstorms, and

something has to give.

Debo is not optimistic about resisting the urge toward development. “I don’t think any

of it’s going to happen,” he concedes. “Until we get people in Congress and in the

White House who care about the environment, it’s just going to get worse and worse.”

Even so, there’s reason for optimism. If good stormwater management means good, site-

speci�c design, then ordinary people have a role to play, too. Residential homeowners

who install a new cement patio or driveway might not even realize that they are

channeling water down-grade to their neighbors, or overwhelming a local storm drain.

Citizens can also in�uence stormwater issues within their municipalities. Many folks

know that they have a local city council and school board, but local planning, zoning,

and urban design agencies also hold regular public meetings—unfortunately, most

people only participate in this aspect of local governance when they have an axe to

grind. For the average American concerned with the deluge, the best answer is to

replace an occasional, morbid curiosity with �ooding with a more sophisticated, long-

term interest in stormwater management.