Recommended Reading - “Arbitrary Lines” by M. Nolan Gray
“Arbitrary Lines: How Zoning Broke the American City and How To Fix It” by M. Nolan Gray
Summary
The origins of zoning:
Gray traces zoning laws back to the early 20th century, explaining that they were initially designed to separate industrial and residential areas for health and safety reasons. However, he argues that zoning was also heavily influenced by racial and class-based exclusion. Early zoning codes in cities like New York and Los Angeles were used to segregate neighborhoods by preventing lower-income and minority populations from moving into certain areas. The Supreme Court struck down explicitly racial zoning in 1917, but cities found ways to maintain exclusion through rules like single-family zoning, which effectively kept out lower-income and minority residents.
How zoning shapes cities today:
Gray describes how zoning dictates nearly every aspect of urban development. He focuses on three major impacts:
Housing shortages & high costs: by limiting how many homes can be built in desirable areas, zoning artificially restricts housing supply, driving up prices and fueling affordability crises in cities like San Francisco and New York
Segregation & inequality: single-family zoning bans apartments in many neighborhoods, effectively keeping lower-income families (often disproportionately people of color) out of wealthier areas with better schools and job opportunities
Sprawl & environmental harm: zoning mandates large lot sizes and separates residential from commercial areas, forcing car dependency, increasing emissions, and making cities less walkable
Myths about zoning:
Gray challenges common beliefs about zoning, arguing that:
Zoning is not necessary for safety – building codes and environmental regulations (not zoning) ensure safe housing and prevent pollution
Zoning does not "protect" home values – many vibrant cities without strict zoning (e.g., Tokyo) have affordable housing without harming property values
Zoning does not create "good neighborhoods" – it often limits diversity, innovation, and adaptability, making cities less dynamic
How to reform or abolish zoning:
Gray lays out a case for eliminating zoning altogether or drastically reforming it to allow for more flexibility. He suggests:
Ending single-family zoning – allowing apartments, duplexes, and townhouses in more areas to create mixed-income, walkable communities
Legalizing mixed-use development – allowing homes, shops, and offices to coexist rather than forcing strict separation
Reforming parking requirements – eliminating minimum parking mandates, which inflate housing costs and encourage car dependency
Moving toward "zoning-free" cities – he points to places like Houston, which has no formal zoning but still functions effectively, as proof that cities can thrive without it
Conclusion: a vision for the future
We envision cities that are denser, more affordable, and more inclusive. Gray argues that removing zoning restrictions would make housing cheaper, reduce segregation, and create more environmentally sustainable urban environments. He encourages policymakers and citizens to push for zoning reform as a step toward a fairer and more prosperous future.
Click HERE for your own copy of the book “Arbitrary Lines”.
In Arbitrary Lines: How Zoning Broke the American City and How to Fix It, urban planner M. Nolan Gray takes a deep dive into the history of zoning, its consequences, and how we can create better cities by reforming or even eliminating it altogether.