Urban sustainability is about more than low-energy
light bulbs, mass transit, and carbon
footprints. It’s about how we manage the
world’s growing urban impact. The fact that
51 percent of the population is now concentrated on
only 2 percent of the planet means we need to design
urban environments that have minimal impact on the
ecosystem while also being resilient to external threats.
The scope of the challenge is neatly summed up
by Northeastern law professor Lee Breckenridge, who
says that urban sustainability “requires looking at
how cities fit within ecosystems and how they depend
on ecosystem dynamics both within and outside of
Urban sustainability presents intertwined issues of
environmental protection, economic viability, and
social equity, she says. Cities cannot be sustainable over the longer term if their economic growth impairs the
environment that they depend upon for clean air, fresh
water, food supplies, and other ecosystem services.
Globally, the sustainability of human life—including
that of poor and vulnerable populations—requires
both equitable distribution of economic resources and
protection of a healthy environment.
As urban populations soar, cities face growing
dangers of linked environmental, social, and economic
crises. The issues are multifaceted and interconnected.
Designing sustainable urban systems requires an
interdisciplinary approach that incorporates scientific
inquiry, technological innovation, legal coordination,
and new policy ideas—just the direction in which Northeastern
researchers are headed.
ALTERNATIVE ENERGY AND
The science-based solutions coming out of Northeastern
labs are focused on sustaining the urban infrastructure
through resource conservation—saving both
energy and infrastructure itself.
Northeastern researcher Sanjeev Mukerjee works in
an area that often leads any discussion of sustainability—
alternative energy. The chemistry professor, who heads
Northeastern’s Center for Renewable Energy Technology,
is working with colleagues at the university and in
private industry to develop a catalyst for low-temperature
fuel cells that is cheaper and more plentiful than the
metals currently used, such as platinum.
Mukerjee says the ultimate goal of his work is to
replace “all combustion-related power sources with
an electrochemical energy conversion and storage
system”—in short, a better battery that could revolutionize
how we power all sorts of systems that are part of the
urban landscape, from laptops to vehicles.
“Urban settings are becoming increasingly reliant on
alternative energy,” says Andrew Myers, assistant professor
of civil and environmental engineering, “and as such
we need to understand the vulnerabilities of emerging
alternative energy structures.” Myers’ research in wind
turbine vulnerability bridges the gap between urban
sustainability and urban resiliency.
“Traditionally, building design has focused on promoting
the safety of life, and that’s what building codes
are designed for. What they don’t do is ensure performance,”
said Myers. Today, structural engineers are
beginning to explore ways to minimize physical damage
to the structures themselves, easing the impact of natural
disasters on urban environments.
By modeling the resilience of various types of
wind turbine designs
and hurricanes, Myers
hopes to minimize the
with these new types of
also looking at urban
resiliency from a
“I think structural engineers should own this space,”
says civil and environmental engineering chair Jerome
Hajjar. “The construction and use of commercial and
residential buildings account for about 40 percent of
our energy use, about 40 percent of our waste production,
and about 40 percent of our greenhouse-gas
emissions.” According to Hajjar, the industry is in need
of transformative, cost-effective solutions and urban
building needs to be at the top of the list.
Hajjar was recently awarded two new National Science
Foundation grants with this effort in mind. One will look
at the points at which energy is lost from a building and
how novel materials could minimize that loss. Another
will focus on steel structures built with materials that can
eventually be disassembled and reused instead of demolished,
eliminating a huge portion of the nation’s waste
output. While many of those materials are now recycled,
not sent to the dump, Hajjar’s team is focusing on the
idea that reuse leads to less energy required for construction
than recycling, as well as less waste.
“I’d like to try to kick things up a notch with a much
richer level of understanding through analysis of the
actual energy that goes into constructing structures and
having that be integral to the design process,” says Hajjar.
Standard imaging can’t answer the question:
“What does a bag of
explosives look like?” says
Rappaport. But the wave-based
developed in his lab can.
There are probably infinite technical solutions to the
problem of urban sustainability, adds Wadia-Fascetti.
“But they aren’t going to be successful if we don’t have
an impact on human behavior. We have to understand
what drives human behavior and what drives
it to change.”
POLICY SOLUTIONS IN
This is where sustainability thought leaders like professor
Matthias Ruth and associate professor Gavin Shatkin come into the picture. Their interdisciplinary approach
looks at sustainability solutions in the context of whole
systems and societies—really, the only way to look at
them, says Shatkin, because “urban sustainability touches
on every aspect of the interaction between people and
the world they live in.”
“These are really complex systems,” says Ruth, who
has joint appointments in the College of Engineering
and the College of Social Sciences and Humanities.
“What I’m trying to understand is how the different
aspects play together, using computer modeling so that
we can anticipate some of the undesired consequences of what we think are solutions.” That analysis needs to
account for the impact on each area of a system—
hydrology, energy, public health, economics, and
For example, in Beijing, improvements in the power
grid have led to increased air conditioning use. “Air
conditioners actually heat up the environment and produce
more air pollution,” says Ruth. “And then we’re
not better off at all, because we’ve actually significantly
changed the local environment. We often find that
our interventions, when not fully thought through and
properly implemented, result in outcomes that run counter to our intentions. The case of using more air
conditioning as we heat up the urban environment is
one of many where we seemingly get locked into unsustainable
Asian cities are an area of particular concern for
Shatkin, who notes that urban populations there are
growing at tens of millions of people per year. Costly
“new town” megaprojects, or planned cities, are among
the leading approaches to dealing with this influx, but
they have the potential to cause major ecological impact
through increased vehicle use, increased consumption,
and the conversion of agricultural land to urban use.
The megaprojects are also socially unsustainable for similar reasons. “These projects are premised on the
desire to maximize economic growth,” says Shatkin, “yet
this is a model of economic growth that concentrates
the wealth in the hands of the wealthy”—promoting
more consumptive lifestyles at the expense of lower-resource
ones, like small farms and businesses.
“In my research, I am exploring the factors that are
driving governments to pursue such projects,” despite
their negative effects, he says.
RETHINKING THE COST OF CHANGE
It may just come down to a widespread belief held by
many policymakers and ordinary citizens alike that the
cost of sustainability outweighs the benefits.
But Ruth says that is a faulty calculus. If we embed all
the costs of doing things the wrong way, he says, we’ll
soon begin to realize that the high dollar cost of green practices is an illusion. For example, he proposes instituting
regulations and economic incentives that more
accurately reflect traditional energy’s true costs—such
as climate change or international security. When we do
this, he says, “then suddenly the alternatives don’t look
so noneconomic anymore.”
Educating high-level policymakers, he says, is an
obvious and important step. But working from the bottom
up may be even more critical: “Probably the most impact I have is in how I teach and educate the next
generation of decision leaders,” he says.
According to law and public policy professor and
interim dean of the School of Public Policy and Urban Affairs Joan Fitzgerald, that education should focus
on the synergistic potential of urban environments.
Their density has the potential to allow city residents to rely less on cars and more on energy-efficient land-use
practices. But because policy areas are implemented
with a fragmented, piecemeal approach, says Fitzgerald,
“they don’t add up to a transformative strategy.”
In order for that next generation of decision leaders
to successfully work toward the vision today’s researchers
are starting to draw up, “they need to be able to
think comprehensively about how all the systems in a
city connect,” Fitzgerald says.
Architecture and urban landscape professor Jane
Amidon offers an example of such comprehensive
“We can be doubling and tripling up on functionality
in the way that we design our public spaces,” she says. For
example, the Fresh Kills Landfill to Landscape project
on New York City’s Staten Island incorporates outdoor
recreational space with ecosystem rehabilitation.
“It’s not just the symbolism of a green public space,
which costs a lot to maintain economically,” says Amidon.
“It’s about new green infrastructure created from
previously contaminated industrial use.”
Such projects are traditionally associated with the
wealthier areas of a city, as they reflect higher real-estate
values, but a truly sustainable city provides access to
these resources across socioeconomic classes.
“We’re not just trying to re-create a natural condition,”
she says, “but to understand how systems function
and leverage them in an appropriate way, economically,
socially, and environmentally.”