The Bay Area is actually denser already than many U.S. metro areas, and regional groups like the Greenbelt Alliance are actively trying to encourage infill development, increasing housing density within the urban footprint of a city rather than expanding the urbanized areas. The Association of Bay Area Governments has mapped places for infill development, and outlines changes to zoning and tax codes that could make infill development more possible. The Metropolitan Transportation Commission has promoted transit-oriented development, to support this infill development. Despite all these efforts, I was struck during conversations in the Bay Area by how controversial infill development can be. Change is hard. It is hard for people to accept changes in neighborhoods they have come to know and perhaps love.
I have come to believe that in the proper places, environmentalists need to argue for allowing more development. As part of a well-planned city, allowing more density near urban centers would prevent sprawl and economically revitalize urban centers.
It will limit suburban sprawl, and help protect biodiversity in remnant habitat patches on the fringes of the city. Development alone won’t, of course, ensure that housing prices are affordable, and cities will also need to have programs to ensure some affordable housing for lower income residents. But allowing more housing units on previously low-density parcels will help reduce housing prices somewhat city-wide.
The alternative to infill development is clear: U.S. cities will continue to sprawl out. While much has been written about the preference of millennials for urban life, the overwhelmingly majority of new houses in U.S. cities are still built on the urban fringes. One of the greenest things U.S. cities could do is get a bit denser. This push for infill development and walkable development is not a new thing for urban planners and new urbanists. But for the conservation movement it is still a new, sometimes hard step, to openly call for more development in certain key, appropriate places.
I saw this in my own city of Washington, D.C., where there was an effort to develop a light rail line (the Purple Line) on a previously cleared old railroad right-of-way, bought by the city decades before explicitly for this purpose.
This effort has been delayed and stymied by landowners along the route worried about the loss of a few hundred trees along the rail line, and the change that will come to their neighborhood as more people can access it. Some local environmental groups have fought the Purple Line, to protect those few hundred trees, but most have fought to allow the rail line to happen. Infill and denser development have to happen for the greater environmental good, and it is a sign of maturity for the conservation movement to be willing to say so.