Streetsblog has an interesting interview with John Norquist, the president of the Congress for the New Urbanism. He discusses boulevard design, highways' impact on cities, and the benefits of dense, local street networks.
He also discusses a CNU proposal to use federal funds to encourage the latter:
The first step is to allow federal funds to be used to bring street networks up to a standard of 150 intersections per square mile. So if you have a suburban sprawl kind of situation where the intersection density is like at 40 per square mile, if you have a project that’s going to bring that intersection density up to 150, then the state would be eligible for getting federal funding to go in and do that.
As much as I prefer grids to cul-de-sacs, I think this is a bad idea.
First, it’s important to distinguish between local street networks and major arterials like boulevards and highways. States and the federal government (indirectly) pay for most highways, while cities pay for most boulevards and other arterials. Norquist rightly complains that the feds have shaped highway design and location for decades. Not to mention the mix of highway and transit spending.
Local streets are different. Local street networks look like they do because cities don’t build them anymore. They instead are platted, built and paid for by subdivision developers. They don’t become public streets until dedication, when cities take title and the responsibility for maintaining them. Cities thus have privatized their grid design. We should not be surprised, then, that developers ignore spillover benefits -- especially connectivity -- when laying out their streets.
Cities do plat and build the arterial roads that link subdivisions to the rest of the city. But we can’t get intersection density by redesigning arterials. Arterials are one-dimensional; grids are two-dimensional. CNU understands that, which is why it wants federal funding for local street networks with a minimum intersection density.
I’m sure developers would be perfectly happy with CNU's proposal. It would eliminate one of their two major infrastructure costs. (The other is running connections from the subdivision to the local water, sewer and electric lines.) Developers would lose some developable lots because a dense street network needs more pavement than the minimal street networks developers build. But I’m sure developers would gladly give up 10% of their buildable lots if cities would agree to build their streets.
Do we want to abandon developer-financed local streets? Even if cities and the feds paid just part of the cost, this would be an immense expense. Most cities don't have the money. It would take billions per year -- every year -- to make a noticeable difference in city structure.
It is also a bad idea to subsidize developers and property owners. Reducing the cost of building subdivisions would get us . . . more subdivisions. If you dislike the relentless spread of single-family subdivisions, then you want developers to bear all the cost. (Actually, you should want developers to bear all their costs regardless.)
Such a subsidy could be efficient in theory if it were limited to the extra expense incurred by the developer to densify their street networks. But developers would have no incentive to disclose their true costs, and local officials could not figure that out on their own.
Finally, it is a bad idea to get the feds involved in local street design. If “incentives” meant “funding,” the feds would dictate street layout, just like they dictate highway width, turning radii, and drinking ages. Cities wouldn't use their scarce dollars to build more than the feds require. Developers certainly wouldn't. And the federal government might not do it the way you or I want it done. Suppose the feds, thanks to lobbying by property owners and developers, decided to fund only 100 intersections per square mile? Or 75? Then 100 or 75 intersections per square mile is what would get built.
There would be enormous pressure to go with less dense networks since they are cheaper. Developers would continually push for less dense networks even if the cities were footing the bill -- sacrificing 20 houses for road funding might be a good deal, but sacrificing just 10 houses would be a better deal.
So whenever someone wanted to change the rules for local street design, they'd have to run to D.C. That's worked real well in the past, right?