Q. Isn’t urban density a risk factor for transmission of respiratory viruses like that which causes COVID-19?
A. When we talk about the advantages of urban density, we are referring to the number of people or housing units per square mile of land area. This is related to but distinct from the question of crowding, which is a function of the number of people in an enclosed or restricted space, and implicated in viral transmission. Crowding is sometimes a desired feature of city recreational activities (such as a packed bar, concert, or open streets event), but often it is the result of insufficient and inequitably distributed built space. Less housing units per square mile in a place where many people want to live can often mean more people housed per room. Similarly, excessive allocation of outdoor space to cars can exacerbate crowding on sidewalks and in parks.
Public transportation ridership is down steeply during the pandemic, and transit operators face fiscal challenges even as they strive to implement new safety practices. We support fully funding public transportation to insure safe and adequate service especially for those who most need it. Transportation networks need a unified approach to transportation safety, including assessing and mitigating public health risks based on science, appropriately contextualizing relative risks of different transportation modes, and communicating these to the public. The Seamless Transit Principles developed for Bay Area transportation provide a template for reforming governance to support these goals. Bikeshare and other micromobility options-- equitably deployed and operating on complete streets-- can provide people with more alternatives and alleviate congestion both on roads and in transit. Dedicated bus lanes can allow more buses to run with greater efficacy and less crowding.
We can’t avoid a conversation about environmental justice when talking about impacts of the pandemic on cities. Our most vulnerable communities-- those which have been exposed disproportionately to pollution (itself a possible COVID-19 risk), have access to insufficient and inadequate housing, have been allocated insufficient public space, and have had insufficient access to health services-- are those which are seeing the worst impacts of the pandemic around the country. Even if there were an irreducible health risk of density over sprawl (which we do not believe to be the case), then exclusionary housing policies are no solution: they merely allow the privileged to opt out of these challenges, often while still enjoying the cultural and economic benefits of density.
Finally, urban density featuring flexible and diverse land use can enhance resilience to both pandemics and climate change. We don’t all have to live in skyscrapers, but living in environments dedicated to one housing type that require driving for all the activities of daily life are uniquely fragile, limiting both functional and economic responses to disturbance. If cities are urban ecosystems, then single-family detached zoning is urban monoculture. Natural environments do not all look the same, but they do share common features like diversity, modularity, and feedback that allow them to resist and adapt to stressors. We need to incorporate these principles into our human environments across spatial scales from small towns to towering metropolises.
Also see our March 2020 blog post led by Urban Environmentalist Robert Spragg.