Can Population Drive Current Highway Infrastructure Beyond Our Capacity to Maintain it?


My pursuit of information about this topic has yielded less information than I would like. It seems intuitive, though – if our population continues to grow there must be a point where sufficient infrastructure either can’t be produced, or existing infrastructure can’t be sufficiently maintained. I will update this item as I find more information.

Will our ability to sustain our highways will reveal our status with regard to sustainability and overpopulation? Many in North America believe our current population is sustainable, as the birthrate is low compared with that of many other countries, but the highways we travel daily could reveal our true status. If sheer population doesn’t exceed our capacity to maintain our highways, fossil fuel shortages will make it so. Is there somewhere an intersection of the curves where the cost of maintaining existing infrastructure exceeds the tax revenues that support it?

Both short and long term views suggest overpopulation is a problem, even in the United States. Severe degradation of the infrastructure could happen in the short term as the economy sags under the burden of increasing fuel costs, thereby reducing tax revenues. In the long term this could occur as population stabilizes and declines worldwide. The short term situation may not be far off in North America, where major highways seem to be decaying through insufficient maintenance and major bridges seem to be at risk or even failing (like the I-35 bridge in Minneapolis (link). It is basic fact that the cost of maintaining any item of infrastructure will go on and on unless the infrastructure is abandoned, while the cost of new construction (admittedly also increasing) stops when the new facilities are opened for use. By that principle alone, funds available for new construction should decline relatively unless tax and other supporting revenues can keep up, which has seemed more doubtful as energy prices rise and begin to drag down the U.S. economy (and others).

Ancient road-building societies never reached the dense populations we have today. The Romans and Incas may have had a better understanding of such things than we do today – their roads appear to have lasted a lot longer than ours are (including after the empire that built and maintained them fell apart). They took centuries to build a lot fewer miles of roads than we have built in a handful of decades, and didn’t have vehicles with the numbers, weight, or speed we do. While they built and maintained their roads with human and animal labor, we have been doing it with the input of a lot of fossil fuel energy, a non-renewable resource we are already beginning to exhaust, as evidenced by rising prices. We are definitely building a great deal more infrastructure than they did, but we have a world population that can be estimated at twenty times that of the world in 1 B.C. (link). Also, we are far more mobile and use far more energy and other resources per person than our predecessors of centuries or millennia ago.

Studies I have found relating to highway infrastructure construction, renovation, and maintenance costs were all locally or regionally focused, and I am discouraged by my ability (so far) to find scholarly papers taking a broader approach to the topic. In any case, I will continue to research this topic from time to time, and will write on it again when I feel I have sufficient new information.

As always, I welcome your comments. – Tim

Interesting Reading:
Report Card for America’s Infrastructure, the American Society of Civil Engineers

Advertisements

2 responses to “Can Population Drive Current Highway Infrastructure Beyond Our Capacity to Maintain it?

  1. It would help if there were more options than just highways.

  2. Michael Kirkpatrick

    Try looking at the AASHTO Bottom Line Report as a place to start. Bascially, this is a compilation of all state DOTs road/transportation needs to maintain the nation’s roadways, waterways, railways, etc. IT is usually created in advance of upcoming legislation.

    And, yes, we (USDOT Highway Trust Fund) have run out of money to pay for it, but that just means we need to find a better way of charging people for it’s use. Gas taxes are a poor proxy for highway use, especially as we push for higher MPG. But, no poltician wants to tell the American public that they ‘can’t’ drive or that what we used to supply ‘for free’ is now subject to fee. By golly, that’s Social Engineering.

    Eventually, we will charge people by the mile (tracked by GPS). Of course, it will still be up to politicians to set the rates. And, this will still require leadership.

    $4-$5/gallon gasoline seemed to be the tipping point where people stop driving. Will the polticians have the guts to set the rate to force drivers out of the market? (or, we can wait and the Chinese and Indians will eventually do it to us) And what about freight? We will still need to get the essentials of life to our nearest Walmart. So, regardless, of our personal driving, we will still pay more.

    And we haven’t even talked about carbon and other social costs of cars/emssions….

    Actually paying something closer to the real price of highways will eventually pare them back to a managable level. Until then, bikes, pedestrians, trains, and buses will be second-class citizens and systems.

    A tall order.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s