How much space does a car take up exactly? The answer, of course, is that it depends - on the design of the place, the type of driving going on, the density, the tendency of the population to build new lanes and parking lots everywhere, etc. The answer is important because people so frequently think of sprawl in terms of houses and house size, which is really fairly unimportant until you get into really dense configurations. It's the automobiles that are taking up the space. This is important to understand.
Cars are larger than houses* - at least in terms of their urban footprint. [*at the densities most Virginia municipalities are dealing with]
I think a helpful metric every county should know about itself is its "Pavement Per Vehicle" and/or "Pavement Per Capita" (either works since there is about one car per adult in Virginia). Most counties have the data to calculate this pretty easily and I'd love to do a state index, but unfortunately most counties do not provide that data free of charge.
Three do, however: Charlottesville City, Albemarle County, and Richmond City. Charlottesville and Richmond are two of the most compact cities in the state and both have lots of college students who tend to own cars but not drive them. Their numbers should be similar and at the low end of the spectrum. Albemarle is a largely suburban and exurban county with a population density close to that of the state as a whole. It is fairly affluent, has major state and interstate highways, and should have a number at the higher end (though I think there will be more counties closer to Albemarle than closer to Charlottesville).
So here's the question: how many square feet of pavement dedicated to automobiles (parking spaces, driveways, roads, etc. - not including sidewalks or pedestrian trails) does the city or county have per vehicle?
The data on paved surface comes in all three cases from the municipalities - and props to them for making their data freely available. Charlottesville boasts over 1100 acres - nearly 2 square miles - of automobile pavement. Richmond clocks in with nearly ten square miles of it and Albemarle has over 14 square miles altogether. The data on number of vehicles and residents comes from the 2009 NHTS and the Census, respectively.
Remember that each house today has an average of two to three vehicles if you're thinking about the paved space taken up by each new home. I used ODU's lovely new basketball court to help you get a better idea of the scale.
Why should we care at all about this number? Well paving places over carries a number of costs.
I. Sprawl
This one is too complicated to hash out in a post like this, but space is a finite commodity and large open spaces in cities disrupt the economy of density that makes cities economic engines. Creating more auto space has a snowball effect in encouraging people to spread out more, creating the need for more lanes and more parking. If sprawl isn't something you care about, just skip this one for now.
II. Real cost
How much did it actually cost to lay that pavement? The answer is tough to estimate, but some back of the napkin calculations based on VDOT's averages and some standard development numbers put it somewhere around $18,000 per vehicle for Charlottesville and $45,000 per vehicle for Albemarle County. The lifetime of that pavement is also a thorny question - for most pavement it's 20 to 30 years. Annualized (without interest), we are looking at about $500/year per vehicle for Charlottesville City and $2,000/year per vehicle for Albemarle County. I think it's actually quite a bit more thanks to the number of highways with large axle loads that require dramatically more maintenance (my numbers are based on parking lots), but we'll go with the lower, very round figures - the pavement to drive each vehicle is costing somewhere between $500 and $2000 a year - a number you should think about being tacked onto your other yearly maintenance and fees. I'd love to hear a better estimate of this from someone at VDOT or a county public works department.
Who pays for this construction? The answer is, of course, you. But how?
1. Directly - in the case of private driveways, which make up a very low percentage of these numbers.
2. Through the cost of goods and services. Stores pay to build parking lots, those costs become part of their overhead, and are then passed onto you in the cost of the item. This accounts for about half of the pavement.
3. Property Tax. Local roads and other infrastructure are often maintained by the city or county, which uses property tax revenues to pay for it.
4. The Gas Tax. Theoretically covers major roads and highways. It represents the most direct connection between the users of the pavement and the cost of it - making it the closest thing to a user fee rather than a tax. However...
5. Sales and Income Tax. In Virginia, legislators were unwilling to raise the state's absurdly low gas tax, despite the fact that it could no longer pay for the upkeep and construction of roads. So instead... they lowered it some more! And then made up the difference with an increase in the sales tax and money from the general fund. This means people who drive less and live in more compact places directly subsidize those who drive a lot.
III. Environmental Cost
The added pavement is one of several pollution sources that is killing the Chesapeake Bay. While it's not the largest source of pollution (agriculture is), it's the only source of bay pollution that is increasing every year. Rain falls on impermeable surfaces, picks up chemicals and sediments, and runs off into the bay, creating a giant dead zone in the middle where life is unable to survive, and blocking the sunlight that helps the bay's abundant sea grasses to grow. If you aren't familiar by now with the trajectory of the bay and the cultures that used to live off of it, it might be a good time to go read up.
The collapse of the oyster population - an economic engine for communities along the bay, which once provided over half the world's oysters.
http://www.cbf.org/how-we-save-the-bay/issues/polluted-runoff
Additionally, paving places over makes them ugly and often ruins them for future agricultural use. It also has implications for wildlife and other natural systems. And it creates more air quality problems, though all of these will have to be the subjects of later posts.
Future Growth
I've mentioned before that the Weldon Cooper Center has us adding around 2.5 million people in the next 25 years. If that adds a proportional number of cars to places that are somewhere in between being Charlottesville and being Albemarle (say 4000 square feet per vehicle - I bet that's about Virginia Beach's number), we could be looking at paving another 280 square miles of the Commonwealth. That's an area the size of Goochland County. Sweet dreams.
