A beautiful natural experiment has just been set in motion. The New York Times reports:
For decades, summer weekends on Cape Cod have been filled with sunblock, sand and backups that last for miles.
The source of those tie-ups, the Sagamore Rotary — a complicated
traffic circle that drivers had to navigate to pass over the Sagamore
Bridge and onto Cape Cod — became history on Friday when the four-lane
road that goes right to the bridge opened to traffic from all
directions. Gov. Mitt Romney
commissioned the new road, called a flyover, in 2003, and said he would
“resign in shame” if it was not complete by the end of his term; he is
not running for re-election this year.
The Times’s headline summarizes the optimism nicely:
New Link Makes Road to Cape Cod Clear Sailing
Well, maybe in October. But economics suggests that the Rotary (which I have navigated many times) is not the source of the traffic problem on Cape Cod. The source of the traffic problem is that the beaches of Cape Cod and the roads to visit those beaches have a monetary price of zero or close to zero. At a price of zero, in July and August, there is excess demand to travel to Cape Cod and enjoy those beaches. The result is congestion that cannot be solved by a traffic engineeer.
Reducing the congestion caused by the Rotary will simply enocourage more people to visit the beaches. Congestion will rise and that congestion will again ration the limited supply of beach access and space on the road. Congestion will soon return to the level that existed when there was a Rotary.
My prediction is that some time in July or August you will see articles in the Times and the Boston Globe expressing surprise that the removal of the Rotary did not seem to have the anticipated effect.
You can read more about the economics of congestion and Cape Cod here.
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This problem is similiar to the "horrific" parking situation that is present on most college campuses throughout the country. Administrators of these assets say that by forcing people to obtain fairly expensive parking tags they are limiting the demand for parking spaces.
However, after purchasing the tags the price of parking is zero. The first time someone parks their car in one these parking areas they effectively pay the entire amount of the parking tag. So, if the total tag cost is $300 per semester, the first time they use the tag the marginal cost of parking is $300. When they return the next day, the marginal cost is $0.
At my alma mater, Western Kentucky University, the administrators sought to solve this problem by adding an off campus lot that requires a shuttle bus (it is about 4 miles from campus) and they decided that the tag for these spots costs about 30% less than the standard on campus tag. It has had zero impact on the parking problem. Primarily because parking in that lot has a marginal cost, the time necessary to get from the lot to the campus. In order to make sure you get to class on time, students must be there 30-45 minutes early.
They misunderstood the role that marginal cost plays in the decision to consume. A system that mimics the electronic toll road pass should be instituted. By using a set of variables that would include distance to primary campus buildings, time of day (8:00 AM spots would cost more than 4:00 PM), and total time parked could provide adequate incentive for students to "consume" parking in a more conservative way.
This method also makes it easier to encourage the use parking spots that are in satelite lots. Ensuring that those who are actually willing to pay for these premium spots. Administrators neither understand the importance of marginal costs, nor the profitability associated with charging each consumer what they are willing to pay.
Although, profitability is rarely discussed in institutions that are non-profit.
Your argument seems reasonable. However, your prediction is testable and some time in the future, you should also provide us with evidence that will show if you predicted correctly or not.
Once I have the power to direct large public works projects I will get right on it.
The Cape is a classic geographically constrained problem. Yes, eliminating the Rotary merely moves SOME of the congestion but understand it also removes congestion. Capacity tends to do that. Ask the people using the traffic circle for other than peak period Cape recreational mobility (jobs/shopping/education) if they think your "induced demand" canard is correct. Ask the people along Route 3 no longer stuck in upstream congestion. And make on mistake, that's what you repeat; the oft refuted Hansen/Yuang induced demand claims. I wasn't even true in their study and isn't true here.
The "problem" with "The Cape" is that there isn't "A Problem" nor even simply many problems. For but one example; the area stakeholders are unwilling to address congestion because they correctly understand that that the Commonwealth and municipalities would ultimately oversell any capacity increases and make matters worse. I'll go out on a limb; the people who own the private property on Cape Cod are scared that easy access would infring on the lifestyles they've purchased. Of course my opinion at this point can easily be dismissed as irelevant at least unless my relatives have willed me the properties on the Cape they've owned for generations unbeknownst to me.
Parking on public roads is a national compact. Restricting it is certainly an option. There's no rights being infringed. I just wonder where to draw the line. Interstate trade? FHWA conditional funding? Here's a thought experiment. Withdraw all public parking. Assign ownership to the nearest property. I'll leave the results up to the reader and only point out the "remedies" suggested are but half measures toward this nightmare.
I won't be surprised when the traffic goes back up, either.
what I don't like about this post is the use of an argument that sounds like the anti-road argument I often hear from idiot environmentalists, namely, there is no point in improving roads because it just leads to more traffic. Well, it may do, but more traffic is more people going and doing things they want to do. IN effect, the flow rate of cars per hour into whereever it is you are talking about was being restricted by a bottleneck, which has now been removed. Talking about congestion existing or returning without talking about the figures obscures the crucial question, which is whether more people are getting to go where they want in less time than before. If they are that has to be a benefit. Also, as another responedent noted, there are the benefits to upstream people who will cease to be blocked by the queue for the rotary and the non-peak flow benefits. I am very dissappointed that this site should be citing these arguments because precisely these vague remarks about congestion are being used in the UK to make our roads worse by removing capacity, as the council of Leicester is currently doing all over the place.
My understanding of arguments for road tolls is that increasing the marginal cost of a road will move us closer to the social optimum (social mc = social mb). I wonder, however, how we can tell if we're already there or not, or rather how far from optimality we are. Accounting for time costs, the MC of those in traffic is not zero. Doesn't a toll just move the distribution towards those whose value of wealth is lower than their value of time?
If we assume that the true cost of driving = transport units * cost of such transport units (tolls, gas, etc) + time units * cost of time , I imagine the analysis would change compeletely, especially if those stuck in traffic have a time cost near zero.