Meet the Environmental Paradox of Smart Growth
San Francisco (photo courtesy of Richard Masoner)
A secret truth of smart growth is that it manages environmental impacts by concentrating them and, in some places, intensifying them. For example, if we absorb new growth by increasing development and the number of residents in city centers and around transit stations, research proves that the environmental impacts per increment of new growth on the region as a whole can be substantially less than if the growth is allowed to sprawl ever-outward. But, in the specific areas where growth and development are intensifying, we may also be increasing noise, traffic, and pollution. I call this “the paradox of smart growth” and believe that we serve our communities and our cause better if we acknowledge and mitigate it.
As I argue throughout this book, to move more deliberately toward anything resembling a sustainable future, we need to use land more efficiently and build more compactly. We need higher densities of homes and businesses per acre than we built, on average, in the new development of the late 20th century. We especially must do this in two ways: (1) by retrofitting or “repairing” low-density suburbs, especially by taking advantage of redevelopment opportunities as aging commercial buildings go out of service, and (2) as I also argue throughout this book, by reinvesting and rebuilding in disinvested parts of central cities and older towns and suburbs. Those aren’t the only circumstances in which we should accommodate more people, homes, and buildings than we may have now, but it would be a heck of a start.
The rewards are substantial: less pressure to develop rural lands; reduced rates of driving, and cleaner air through consequent reduced emissions; more walkable neighborhoods and more viable public transit; cleaner waterways through reduced spread of runoff-causing pavement around what are now well-functioning watersheds; increased tax revenues for cash-strapped local governments; and opportunities to apply design lessons so that we may create better places. That’s a lot of benefit. While I am on record as saying that we don’t necessarily need high densities to achieve these improvements, we certainly need to do much, much better than sprawl.
But there’s a catch: Smart growth lessens the harmful impacts of development not just by concentrating development but also by concentrating impacts. It reduces emissions, runoff, traffic impacts, and intrusions on now-green land regionally in part by increasing them locally. Long-time residents of communities where intensification is occurring sense this intuitively. And that, in a nutshell, is why so many people fear and oppose even environmentally sound development.
All too often, I think smart growth advocates ignore development opposition (“we’re right and they’re wrong”) or simply seek to overpower it politically. (Wise developers, to their credit, often negotiate with opponents, frequently succeeding in getting to a “yes” by making concessions that, in the long run, will save them time and money compared to legal battles. Urbanist policy advocates generally lament these concessions.)
Some pro-development commentators are starting to suggest a different strategy: acknowledge that NIMBY (“not-in-my-back-yard”) fears are frequently well-founded and address them with changes in design, policy, and process that respect their concerns.
San Francisco neighborhood, 52.5 homes per acre (image via Bing Maps)
Boston neighborhood, 52.9 homes per acre (image via Bing Maps)
Writing on her planning firm’s blog Placeshakers and Newsmakers, Susan Henderson suggests that municipal planners trying to win hearts and minds to new development should be more sensitive to building types that fit well with existing neighborhood character. Zoning codes that simply prescribe maximum and/or minimum densities for particular places don’t do that, she says, and as a result density targets can be achieved in wildly varying ways that can help or harm a neighborhood.
Consider the contrasting images of a newer neighborhood in San Francisco and an older one in Boston (both aerials and street views are included with this essay). They look and feel totally different. But they achieve almost the exact same neighborhood density, 52.5 and 52.9 homes per acre, respectively. Henderson prefers the Boston example (as do I), but that preference could be for residents to decide. The zoning code should be written accordingly.
San Francisco neighborhood, 52.5 homes per acre (image via Google Earth)
Boston neighborhood, 52.9 homes per acre (image via Google Earth)
Henderson makes another critical point that both urbanists and environmentalists must grasp: it’s the average density that matters, not the density of a particular building or parcel. One can achieve a desired density through combining a variety of building types—for example, single-family homes with grassy lots, townhomes, and multistory apartment buildings—working together. There are older neighborhoods in my hometown in North Carolina—and probably in many communities with older neighborhoods—that mix these building types seamlessly, achieving densities much higher than sprawl while retaining a human scale.
It is a tragedy that, at some point, we started outlawing such mixed districts and, instead, began creating suburban pods of identically-sized buildings, places where all the houses are single-family with 1/3-acre lots, or all are townhomes or multifamily. As a result, people interact with others much like themselves, at least in terms of housing preferences, and lack much opportunity to interact with those who aren’t. This is the American Dream? We can do better.
My friend Lisa Nisenson is addressing these issues from the process side. When we first met quite some time ago, Lisa was working in what was then known informally as EPA’s Smart Growth Office (it had a longer and more bureaucratic name). She has since developed her own business as a consulting community planner. Lisa believes that conflicts over development arise at the “edge” where new development meets old, and that the planning profession has not been sufficiently forward-thinking in respecting the concerns of those who are fearful and creating a framework for resolving them:
“I’ve long been frustrated with planning at this edge (having started my planning career in Arlington (VA) as an activist living on this edge but supportive of Metro-oriented density). My main complaints are:
- “There are legitimate concerns on livability that can be better addressed if included at the front end of the planning process: noise, circulation, design, restaurant smells, parks, drainage, parking, garbage pickup, traffic, loading and deliveries, crosswalks.
- “There are also long term impacts that can be better managed when maintenance and management are front-end topics.
- “There is no organized, central repository where local decision makers, developers and homeowners can go to see policies, stipulations, maintenance agreements, photos, plans and graphics that have worked (or fell short) in other places.
“If this is a top reason why good redevelopment and density do not take place [because opposition thwarts it], why are we not addressing it as a planning imperative?”
Lisa has authored a publication titled Density and the Planning Edge for the American Planning Association’s Zoning Practice series. In it, she cites a survey finding that the top three reasons why Americans oppose development are, in order: protecting community character; protecting the environment; and too much traffic. All can and should be addressed early, she writes, through such measures as policies to protect historic resources, design guidelines to protect community character, requirements for adequate park space and tree canopy retention, noise ordinances, and detailed street and transit standards.
But planners may lack familiarity with the right measures. Lisa argues persuasively for a national repository of best practices in preventing and mitigating locally harmful effects of density, and in engaging nearby residents to ensure that their concerns are fairly heard and addressed.
Before closing, I want to make a plug for what I consider one of the best tools for softening density and mitigating the environmental paradox of smart growth: nature. As elaborated in an earlier chapter, I believe that nature has an intrinsic appeal for humans and, if we design density so that it brings more nature into communities, density could become far more appealing and popular.
Quiet green spot amid density, New Orleans (photo by F. Kaid Benfield)
And I would particularly urge that the nature we integrate into development—plantings, water, trees, open space, green courtyards and roofs, living walls, and so forth—be designed to serve multiple purposes simultaneously. A menu of choices for multitasking might include, for example, green infrastructure to catch and filter stormwater, places of play for kids and respite for adults, plantings that maximize the absorption of carbon dioxide while releasing oxygen for cleaner and fresher air, green spaces that reduce the heat island effect, and/or signature public spaces to create a sense of place. These can be mixed and matched as circumstances allow, or even all combined into a single space.
It may sound somewhat counterintuitive to link density and nature, but it isn’t, really. (Ben Welle, formerly of the Trust for Public Land’s Center for City Park Excellence, believes they are mutually dependent.) Even the smallest parcel can make some sort of contribution. As someone in the business of selling more density and urbanity to a frequently distrustful public, I can’t tell you how much it would help, and it seriously bugs me that advocacy for urban nature is not a larger part of the smart growth agenda. We’ll never make much progress by ignoring the local challenges that smart growth can present.
More about the Paradox
How Much Urbanism Is Enough?
Despite the paradox of smart growth, urbanism remains a choice we must make, because the benefits of density can outweigh the detriments, both for the planet and for people. But, as Henderson and Nisenson both suggest, we will do a much better job of it if we identify and mitigate the potential detriments.
For example, what about my spouse, who likes to visit and enjoy cities but likes to retreat from them even more? In her heart she prefers a nature trail or even the relative peace and quiet of a suburban backyard. I’ve mostly converted her to the smart growth paradigm, and she understands that to save nature we must cluster more in cities. But she’s an introvert, and not really a city person by instinct.
We compromised by settling in a relatively quiet, moderate-density city neighborhood, but even there I confess to some irritation when my neighbors (and one aspect of small-lot, city living is that there are a lot of them) seem to think the best way to spend a nice spring weekend day is to bring out some power tools in their back yards and do whatever it is that people with power tools do, loudly. We like to sleep with the windows open, but on nice evenings the 20-somethings in the group house across the street like to hang out on their front porch until the wee hours. Who wants to sleep with earplugs?
Mass transit isn’t always the most pleasant and nourishing experience, either (though it sometimes is). So what are we advocating, exactly?
Scott Doyon is one of Susan Henderson’s partners in the town planning and development advisory firm PlaceMakers. In his own article on the firm’s blog, Scott argues that urbanism has been the right reaction to sprawl but now needs to be tempered to accommodate the human need for occasional retreat from social interaction:
“We…took the suburban promise of independence and personal space to some pretty ridiculous—and dysfunctional—extremes but, in attempting to correct them, we’ve since made the mistake of confusing the need with the manner in which we satisfied it.
“Simply put, sometimes the last thing we want to do is experience another person. And that’s okay. Very few (perhaps none) of us are ‘on’ all the time. At times, we do need to pull back, to be alone or with intimate gatherings of carefully chosen people.
“Community, for all its benefits, is a tiring endeavor. But that’s a hard thing to consider when the larger conversation…is focused on all the measurable ways urbanism can help us solve our problems—from the environmental to the economic to the social.”
Scott closes by reminding us that we need to design and build better places for privacy within compact development. Not necessarily more of it, but better. Food for thought.
Walkable but relatively peaceful density, Washington, DC (photo by F. Kaid Benfield)
Wendy Waters, who researches and analyzes urban economic trends and writes the blog All About Cities, seems to agree. Comparing locations with different Walk Scores, she suggests that the urbanist Holy Grail of a perfect 100 score may not be for everyone. She likes her own neighborhood (Walk Score 98), but concedes that a high volume of traffic and noise and a lack of privacy can all be aggravating. A still urban but less intense setting might be better:
“A couple decades ago, few people wanted walkability–they wanted quiet, or the perceived security of auto-centered life. Today, many want the opposite. But maybe we’ve gone too far in thinking everybody should have everything close by? Perhaps even more people would embrace an urban life with an 85 Walk Score?”
The comments on the post add interesting perspective to the discussion, most of them also using Walk Score while discussing the tradeoffs of urban living. One commenter said that she would gladly give up “ten, twenty, even thirty points” in Walk Score to get away from the noise. Responding to the comments, Waters writes that “in many cities and neighborhoods there are almost-linear balancing opportunities between extreme-walkability-with-noise vs. increasingly quieter or more private living, but a need to walk a few extra blocks.”
I think this may be an issue we haven’t completely figured out yet. I suppose one too-easy answer is that there never has been and never should be a one-size-fits-all approach to smart growth and urbanism. We can and should provide a variety of environments that offer a range of living choices while staying well within the framework of sustainability. People who value community over quiet should be able to choose that, and vice versa. New urbanism offers the urban-to-rural “transect” as a way of providing different levels of appropriate urban intensity in different parts of a region.
But the availability of choices within urban settings can be tough to realize on the ground, where real-world development occurs in limited-scale, scattered fashion, one parcel here, another there, with developers eager to maximize returns on investment. In the DC area, I’m not seeing many proposals for moderate density (say, 10 to 20 homes per acre) except in the far outer ‘burbs where it won’t do much good environmentally, even if builders can find buyers for it. For infill and transit-adjacent projects, I’m seeing plenty of urban intensity, but hardly ever a park or the kind of tranquil, publicly accessible courtyard that can provide an antidote to hyper-urban settings.
Is more attention to moderate density, in more places, part of the answer? Maybe, and so is better design. But perhaps there are other answers, too. That we must have more urbanism is not up for debate, as far as I’m concerned. So let’s keep working on getting it right, and making it better.