Law and Sustainable Urbanism
Legalizing Walkable Cities to Save Your City and the World
I’m starting this “Law and Sustainable Urbanism” series to publish some ideas that have come together as I’ve worked on my graduation writing project at ASU Law School in beautiful downtown Phoenix, AZ. I’m forever grateful to Professor Karen Bradshaw, a venerable scholar of sustainability who first set me on my quest to understand walkable cities and how they fit into the broader themes of law and sustainability.
Too hot and sprawling to ever walk or bike? The Valley of the Sun has more potential for active transportation than you might think.
Climate change mitigation and adaption is one of the most important aspects of 21st century city planning. More than half of the world’s population lives in urban areas, which the UN predicts will rise to two-thirds by 2050. In a global survey of major cities, three quarters of them indicated their planning and development priorities included climate change issues. In the US, where 86% of the population is urban, cities can work to meet the Paris Agreement targets despite aggressive opposition on the federal level.
Moving people and goods around consumes about a quarter of global energy, so there are enormous opportunities to cut emissions in the transport sector. Globally, transportation accounts for around 15% of greenhouse gas emissions, but this figure is higher in large wealthy nations with high car ownership like the US (29%) and Canada (24%). Even major US states and cities like California and New York that aggressively set and reach emissions reduction goals recognize the transportation sector as “a major challenge.” Compact development mitigates climate change directly by reducing the need to drive for everyday trips.
Three factors determine the level of transportation emissions: the efficiency of vehicles, the type of fuel they burn, and the amount they drive, measured in vehicle miles traveled (VMT). Unfortunately, improving fuel efficiency standards and making fuel “cleaner” requires technological breakthroughs that come more slowly than measures to cut VMT.
In an improving economy with low gas prices and more people moving to larger, sprawling metro areas built under the 20th-century model based on cars, we can expect people to drive more often and further distances. To tackle greenhouse gas emissions from the transportation sector, authorities necessarily should focus on reducing VMT.
Proven ways to lower VMT include encouraging transportation other than personal cars like transit, walking, or biking; policies that equitably share the societal cost of car dependence like a carbon tax, congestion pricing, or elimination of parking minimums; and enabling higher density and mixed land use to reduce the distance between destinations.
Research shows that compact, mixed-use, small-block, and infill development can reduce VMT per person by eliminating or shortening car trips. The more people live and work in a given area (population/job density), the more sustainable, accessible, and affordable that area’s transportation system will be. Fostering walkable cities is not only key from public health, equity, and economic perspectives, but plays a central role in mitigating climate change.
My own experience growing up with poor access to mobility inspires me to work to create more accessible, affordable transportation than I had. This goal, combined with a certain amount of climate change induced existential dread, means I’m probably more excited than most for the future of sustainable mobility. The possibilities are immense for radical improvement in everyday people’s lives by designing cleaner, safer, more equitable ways of getting around that also help address the central environmental and economic threat of our time.
