A recent article in Access magazine examines the effects of parking requirements on urban density, and compared the densities of Los Angeles, New York, and San Francisco. It shows that off-street parking requirements explain much of the difference in the density of these cities. It concludes that the simplest and most productive reform of American zoning would be to declare that all existing off-street parking requirements are maximums rather than minimums.
"Planners and urban criticswho regularly call for increased density as a salve for city life should realize that without corresponding changes in parking requirements, increased density will compound, rather than solve, the problems we associate with sprawl."
[Editor's note: The link below is to a 1MB PDF document.]
Thanks to The Practice of New Urbanism