One of the strange things about freeways is that if they are managed properly, far more vehicles can be carried on them than if they operate on a free-for-all basis, as is currently the case.

The reason is that when freeways are full — but still free-flowing — and traffic is moving around 55 to 60 mph, each freeway lane can handle more than 2,000 vehicles per hour.

However, when automobile freeway speeds drop down to 30 to 40 mph, traffic flows become unstable and motorists start to experience waves of starts and stops, often for no apparent reason. It is for this reason our freeway lanes will only carry 1,500 vehicles an hour at such congested speeds.

That means that if we were able to smooth out the traffic, we would be able to carry one-third more vehicles on our freeways during the rush hour and get commuters into and out of town much faster than we do currently.

The problem is that the only practical way to take advantage of this is through congestion pricing; it is the only remedy that has worked elsewhere.

Congestion pricing is the use of tolls collected seamlessly by way of an electronic recording device placed in the windshield that charges your credit card for highway use as you pass by roadside signals.

The closer you drive to the peak of driver demand, the higher the toll. The desired outcome is that with carefully graduated pricing, motorists distribute themselves evenly throughout the peak period.

Here's the principle: When our demand for things exceeds the supply, which is the case in virtually all the other economic transactions we make in life, we price them differently so that the demand comes into balance with the supply.

We price hamburger differently than T-bone steak, although they cost the same to produce, because the demand for each is different. Demand, and thus pricing, for telephone and electricity service tends to differ by time of day, even though the cost to produce it is the same.

The only other ways to manage supply and demand is by rationing or waiting in line. Presently, waiting in line is what rations peak hour freeway space; daily we have thousands of automobiles all lining up to get into and out of downtown.

However, while pricing offers an opportunity to eliminate traffic congestion, it will be difficult for our officials to come to grips with it.

Elected officials never want to convey unpleasant news to constituents, and pricing roads that were formerly free is, at first blush, bad news. This is why our federal elected officials set up institutions like the base closing commission.

If we are ever to adopt congestion pricing, it will have to come as a demand from voters, and that will only come when they eventually understand the advantages of it.

The greatest danger in congestion pricing here is that elected officials will want to spend the added toll revenue on pet projects, and the last thing we need is another tax. But we could remedy this by way of a Congestion Pricing Commission that would reduce gas taxes to offset the toll income. The commission's mandate would require it to ensure that, administrative costs aside, the scheme be revenue neutral.

Britain's minister of transportation announced recently that such a plan would be in place nationwide by 2014. Britain will eliminate gasoline taxes and instead charge motorists a basic small amount per mile for highway maintenance, and an additional congestion charge per mile according to time and place. To be motoring around London's busy Piccadilly Circus at noon will be very expensive, while traveling on rural roads at 3 a.m. will be cheap.

Congestion pricing now has a solid foothold both nationally and internationally, and it is just a matter of time — maybe a long time — before we see that it will also make sense for us.

Cliff Slater is a regular columnist whose footnoted columns are at: www.lava.net/cslater.