jumping off /u/secondnameIA 's recent post again.

TL:DR, Strict separation of uses and parking minimums have more of an impact on walkability at the typical urban (and even most suburban) neighborhood scale than density restrictions.

They sparked a good discussion about small town density and the relationship between density and walkability, and listing some not so dense small towns that have some decent walk ability (this thread for example). I feel like when we talk about walkable cities we are really talking about the coagglomeration of multiple smaller cities (called neighborhoods in the large city context). I also feel, that almost the entirety of the city walkability discussion focuses on density, which, as we seen that undense small towns can be perfectly walkable, I think is missing the main cause of the lack of walkability in many/most cities. If small towns can achieve walkability at 5,000-10,000 sf lots then density is probably not the limiting factor on urban neighborhood walkability.

Through strict separation of uses and parking minimums common within most cities we have made walkability largely illegal, almost by strict definition, because if there is no where to walk to, well then..... Now, don't get me wrong density is going to correlate with walkability through increases in local market size (supporting more non residential use), and decreasing distance (more people can walk to more parcels). Separating non residential use to only major thoroughfares with miles of only residential use in between, limits the amount of walkable space. This is obvious so no more time needs to be spent. Parking minimums are commonly brought up as detractors from walkability but generally only in the context of making space unpleasant to walk through. Additional attention should be paid to the fact that parking minimums increase the costs of building a non residential neighborhood oriented establishment and, in confluence, increase the burden of non-residential uses on their residential neighbors.

1) When parking minimums are excessive (which I do believe is always) requiring additional parking, for an otherwise presumably neighborhood walkable focused business, increases costs for that business. Through requiring additional land and pavement.

2) These additional costs require that the business have a larger market area drawing more customers from outside the neighborhood.

3) larger and busier (especially vehicular traffic) establishments impose higher costs on their residential neighbors and on their more extended neighbors. And, draw more vehicular traffic into the neighborhood further decreasing any chance of achieving neighborhood level walkability.

TL:DR, Strict separation of uses and parking minimums have more of an impact on walkability at the urban neighborhood scale than density restrictions.

I don't think this is a new idea and really just "arguing" for a shift in what I think is a misdirected focus and putting out there looking to see what you folks have to say. Also, links to anywhere else that this has been discussed would be appreciated too.