Blog

by Philip Ogren

Are cities bad for the environment?

I was recently explaining to a friend why I am excited about the good work being done by YIMBY activists in Boulder and across the country.  She was unfamiliar with the phrase “YIMBY” and so I gave her a quick elevator pitch.^[1]YIMBY stands for “Yes In My Back Yard” which is in contrast to NIMBYs who can be characterized as discouraging all development everywhere – especially when it might be close to a NIMBY’s … Continue reading  Her first reaction was “that sounds nice, but do you really think the planet can support denser cities?”  It’s a fair question.  We often have deep intuitions that our ever-growing large cities dotting our globe are the source of all things bad for the environment.  Should we really be investing more housing, more infrastructure, and more raw materials into our cities if they are so bad for the environment?  Because isn’t the whole problem that there are too many people consuming too many resources?  This simplistic conclusion aligns with a frequent emotional reaction to cities – that they are concrete and steel hellscapes that make us feel disconnected from nature.  I often feel a deep urge to leave the city to escape into nature where I can find spiritual nourishment and inspiration for taking care of this amazing planet.  Skepticism of cities is reinforced by images from the media which frequently promotes “green” tiny homes nestled in picturesque settings such as rainforests or mountains.  We have been fed a fantasy that the way to live in harmony with nature is to live in nature with a minimal footprint that integrates seamlessly with the surrounding ecosystem. ^[2]This may have been possible and desirable in previous generations in which the human population was much less than the current 8 billion. Because living in nature is not practical for so many people, many of us settle for some suburban-style distant approximation of this ideal which may include living near nature.  The more remote and the closer to nature we are, the better we may feel about the environment and our relationship to it.  

But this is all backwards.  

Consider the following thought experiment.  Instead of clustering in cities, imagine if we tried to maximize the number of people living in or near natural landscapes. What would this mean for humanity’s environmental footprint?  Devastation.  When people are spread out they drive more, they consume more land, and they require more infrastructure in the form of roads, sewage systems, electric lines, etc.  Now do the inverse thought experiment.  Imagine what humanity’s environmental footprint would be if we lived in the most space efficient housing possible.  There would be less driving and fewer roads.  Smaller houses and other buildings would require fewer resources and supporting infrastructure.  Both thought experiments when taken to an extreme sound pretty miserable for the planet and humans^[3]This video imagines what it would be like if all of humanity lived in a single building with a footprint the size of the Faroe Islands.  https://youtu.be/O1DeSLZkPrg, respectively.  But it is important that we upend some of our misleading intuitions and understand that urban centers and compact living are key to lowering humanity’s impact on the planet.

Four Future Scenairos

In his 2013 book “Urbanism in the age of Climate Change”, Peter Calthorpe claims that “Urbanism is, in fact, our single most potent weapon against climate change, rising energy costs, and environmental degradation.”  The premise of the book is that urbanism is a key ingredient towards getting to the 12% Solution: the goal of having each person emitting 12% of current levels of greenhouse gases by 2050 in order to mitigate the worst effects of climate change.  In order to underscore the importance of urbanism and increased density for reducing environmental impact he provides the following 2×2 grid which imagines four different futures: 

	standard development	smart growth
current policies	Trend Sprawl	Simple Urbanism
green policies	Green Sprawl	Green Urbanism

four possible futures that combine two land-use alternatives with two alternative policy packages

Trend Sprawl – in this future we basically keep doing what we are doing with respect to land use and energy policy. In this future, the supply of fossil fuels continues to expand to meet energy demands which are mitigated somewhat by modestly improved auto and building efficiencies.

Green Sprawl – in this future we aggressively improve the efficiency of our automobiles and buildings and similarly aggressively replace fossil fuels with green energy alternatives but we continue the trend of our current land use policies which emphasize car-centric, decentralized, suburban-style sprawl. This is the green future most often promised by the media and politicians who would have us believe that we can continue living the way we live just so long as we start doing it “greener”.

Simple Urbanism – in this future we aggressively apply “smart growth” concepts to our land use policies by moving towards urban infill and compact growth.^[4]Interestingly, he talks at length about Denver’s Stapleton Neighborhood as being an exemplar of compact, mixed-use development. But instead of aggressively pursuing “green” energy and efficiency policies we basically continue on as we are currently trending. This seems an unlikely future given the current political landscape but it serves as a useful thought experiment to compare and contrast with Green Sprawl.

Green Urbanism – in this future we aggressively pursue both smart growth land use patterns and green energy and efficiency policies and technologies. This is the path towards realizing the 12% Solution.

This 2×2 quadrant is a very useful way to think about how we can reduce the environmental impact of human activity because both Green Sprawl and Simple Urbanism have important benefits and drawbacks when implemented in isolation. For example, Green Sprawl would result in a future with much less water and building energy consumption but would result in enormous amounts of new urbanized land and huge vehicle miles travelled (VMT) numbers, and would impose enormous infrastructure costs too. Simple Urbanism, on the other hand, would increase the amount of new urbanized land very little, drastically reduce household VMTs, and impose far smaller infrastructure costs. However, water and building energy consumption would still be very high. Green Urbanism combines the benefits of both smart growth land use policies and green energy and efficiency policies and points towards a feasible way that human activity can be environmentally sustainable.

Growing Greener

What does this have to do with Boulder Colorado? After all, isn’t Boulder held up as a model for environmental sustainability?^[5]Check out this TED Talk about urban land use that features Boulder’s famous bike paths (at around 5:50). I like to remind readers that I have a deep love for this city and I truly admire the concerned citizens who live here and the hard work that’s been done to realize environmentally friendly policies like our network of bike paths and lanes, open space assets that curb sprawl, and climate change initiatives. But if you look a little closer, our collective action looks a lot more like “Green Sprawl” than “Green Urbanism” especially when it comes to the tireless defense of zoning for large single family homes on large lots which make compact development and urban infill all but impossible in most areas of the city. By severely limiting the ability to implement smart growth land use policies, we actually exacerbate suburban sprawl in surrounding communities. This was carefully detailed and argued in the Growing Greener report which was a joint effort by Frontier Group, SWEEP, CoPIRG Foundation, and Environment Colorado. They make the following central claims:

• The inability of people who work in Boulder to find or afford housing in the city encourages long commutes that contribute to regional air pollution and global warming. Three out of five jobs in Boulder are held by people who live outside the city
• Enabling more people who work in Boulder to live in the city would allow them to drive less and walk, bike and take transit more, reducing air pollution and greenhouse gas emissions.
• Enabling more compact development, particularly along transit corridors like Broadway and near commercial centers, could further reduce driving and associated emissions within Boulder.
• Increasing compact development within Boulder would not only reduce driving and associated emissions, but also environmentally damaging sprawling development across the region.
• Increasing compact development can help Boulder to meet its goals to reduce greenhouse gas emissions, increase affordable housing availability and much more.

GROWING GREENER The Environmental Benefits of a Compact and Connected Boulder.

I cannot add much of value to this very well-written and thorough report. I encourage you to make time to read it because it is vital to understanding how Boulder can pursue a “Green Urbanism” future that would make us a model of sustainability that really be worth bragging about.

Green Urbanism and Population Growth

This all sounds fine and well – but what about the underlying macro problem of too many people consuming too much stuff and land and energy and food. What good is it to have a “Green Urbanism” future if humanity’s population and economy just keep growing? I think very few environmentalists would deny that the sheer scale of human population and activity is the single over-arching macro-level explanation for the stress we’ve inflicted on our planet’s ecosystems. Wouldn’t it be better if we simply limited all growth everywhere and shouldn’t we start by stopping growth right here in Boulder? This is a popular argument made by vocal members of our community. But this argument is badly flawed for the following reasons.

• The salient takeaway of pursuing Green Urbanism is that we will need far fewer resources per person right now. Even if global and/or regional population starts to decline we should still actively promote the growth of Green Urban cities where resources consumed per capita is sharply less than suburban lifestyles.
• If global population froze today or started to trend downwards there will still be massive global, national, and regional migration trends that will result in increased urbanization. Some areas will increase in population while others decrease for a wide variety of reasons including displacement of coastal areas due to rising sea levels and droughts caused by climate change. Colorado will likely continue to be an attractive place for people to migrate to for generations to come. Will migrants to our state live in existing cities that have shifted towards Green Urbanism or will we continue expanding our metropolitan footprints with ever increasing sprawl? Similarly, Boulder will likely continue to be an attractive within Colorado for people to come to to live and work. Will newcomers be forced to outcompete established residents for the relatively fixed and limited housing in Boulder or will we make room for newcomers by building compact housing and urban infill projects?
• Urbanization has a very liberalizing effect on people and urban areas are where progressive values and ideas most easily and naturally flourish. ^[6]For more discussion on this topic, check out the podcast episode from The War on Cars from August 19, 2019 featuring David Roberts – especially his closing remarks near the end of the episode. It follows that if you want lower birth rates to mitigate population growth, then an effective way to achieve that is through urbanization of populations.

Conclusion

One of the great things about Green Urbanism as described above is that we don’t have to wait around for the federal government for us to make meaningful efforts to mitigate the climate crisis. And while we are still going to need collective action at state, national and planetary levels to support policies like carbon taxes and efficiency standards, there’s no reason we can’t make meaningful and dramatic change to the environment right here and right now in Boulder Colorado by adopting smart growth land use policies that encourage compact structures, walkable neighborhoods, and mixed-use urban infill.