I have long been thinking about a policy for construction of roads and highways, that would result in no more pavement. A post by Charles Marohn on Strong Towns blog titled “What is the federal role?” reminded me that I’d not posted on my idea. An excerpt from his post:

So if you forced me to have a federal transportation bill, then I would want it to do two things. First, I would want it to place a moratorium on the expansion, extension or construction of any new auto-oriented facilities. No new road miles anywhere. There is no need for this country to ever build another mile, another lane, another overpass or anything — we have far more than we can take care of now, most of it very unproductive. I would make this exception, however: any state that wants a new mile of highway has to remove two miles of existing. This would allow flexibility for states that wanted a strategic contraction, allowing them to allocate scarce resources to areas that would have the greatest benefit. In short, I would ensure the bill funded maintenance (which would make it politically irrelevant in the current context, but that is beside the point).”

I worked for several years in the Lake Tahoe basin, doing watershed education. The policy for hard coverage such as buildings and pavement, which produces runoff to the lake and a decline in water quality, is that there be no net increase in coverage over time. If a developer or homeowner wants to increase their coverage by expanding the areal extent of a building or parking lots, they must retire other buildings or pavement. The policy has been quite effective, and is primarily responsible the reversal in the steep decline of lake clarity. I realized that the policy would be a good one to apply everywhere. Pavement everywhere has the same effect, causing rain and snow to run off, carrying sediment and debris into waterways. Less pavement equals cleaner water. But there are so many more benefits of less pavement to the environment and to livability in towns and cities, that it makes no sense to continue paving, anywhere, anytime.

So, my proposed policy, aligned with Marohn’s transportation bill insight, is:

No Net Pavement

If a transportation agency wants a new highway, they would have to find another to remove. If they want to add lanes to an existing highway, they would have to remove lanes or parking lots elsewhere. If a green field developer want new streets for their McMansions, they would have to retire pavement elsewhere. By the way, almost all green field development (former agricultural or forest land) is for high income single family housing. Almost no middle class or low income housing is now built on green fields.

Or course, if this one-for-one replacement were required, it would be rare for a transportation agency or developer to build anything new. And that is exactly my desired outcome. Vehicle mileage has flatlined, and I think it is unlikely to Increase, due to demographic changes. So do we need to build more highways? We don’t.

We have all the housing stock we need, with a significant percentage sitting empty. The only reason new developments are built rather than rehabilitating or reconstructing old ones is that the developers make more money by shifting their expenses onto society. So do we need to build more single family houses? We don’t.

I think that it will be necessary in the not too distant future for transportation agencies to reduce the amount of pavement in order to maintain what is needed at a reasonable quality. Potholes are proliferating, and expansive pavement makes no sense. We could remove:

• excessive width and underutilized parking on residential streets; give the space to bike lanes, wider sidewalks, and/or back to the property owners, who could build their own parking if that is their perceived highest use
• remove excess parking spaces from parking lots; most parking lots are full only a few days per year; it should go without saying that no parking anywhere should be provided for free, since “free” just means the huge costs are shifted elsewhere
• convert excess arterial lanes to bike lanes and/or cycle tracks and to sidewalks; again, these roadways are at capacity only a few hours on weekdays; we build most things not for the highest imaginable level of use, but for an optimal level of use, and arterials should be no exception
• stop expanding highways, and where no high occupancy lane exists, convert one of the existing lanes to that use; it is well known that highways don’t meet demand but rather induce traffic; if we stop increasing highway capacity, people will start living and working closer

No Net Pavement