Drivers in metro Washington, D.C. are experiencing the new realities of commuting in the U.S., and it’s not pretty: It cost drivers $40 to drive 10 miles on I-66, a main commuter route into the nation’s capital from the western suburbs in Northern Virginia, at one point this week.

Is this the future for private car owners across the U.S.? The answer is yes.

Tolls on public roads aren’t new. But the I-66 toll, which fluctuates based on demand and doesn’t have a ceiling, is by far the most expensive per mile.

This toll at “the peak of the peak rate” reached $34 to drive those 10 miles on express lanes nside the Beltway on Dec. 4, the first day of the new tolls. It then hit $40 at one point during the orning commute a day later. In the next three days, morning tolls peaked at $23.50, at $25.50 and at $14.50. Pricing changes every six minutes during rush hour, or from 5:30 a.m. to 9:30 a.m. eastbound and 3 p.m. to 7 p.m. westbound on weekdays, the only time they are imposed. Those who carpool, with at least one other person, can drive for free.

The sticker shock felt by these drivers is not an outlier; it’s like a harbinger of the future.

Across American, government is facing the reality of a big revenue deficit at a time of huge spending needs for roads. As our roads get older and busier, they need replacement, improvement and much more maintenance. And that’s expensive.

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On the other hand, the Highway Trust Fund — the main way we pay for highways, through a tax on gasoline — is running out of money. The federal gas tax was last raised in 1993, to 18.4 cents per gallon of gas and isn’t indexed to keep up with inflation. At the same time, more fuel-efficient cars mean drivers don’t need to buy as much gas to cover the same distance. That will only accelerate as the shift to electric cars reduces the amount of gas-taxable miles traveled. According to Congress, even with a $143 billion transfer from other federal sources since 2008, the Highway Trust Fund is threatened with insolvency by 2020. Some states have raised their gas tax to shore up their own road budgets, but it is still not enough.

So we need to bridge the gap between declining revenue and the spiraling cost of infrastructure investment. Increasing the gas tax is one solution, but given the changes in car technology, it isn’t enough. That leaves congestion pricing that taxes motorists for driving at the busiest time. It is an alternative revenue source that won’t dry up because of improved fuel efficiency or the shift to electric cars.

Congestion pricing is likely to play a major part in a forthcoming infrastructure bill that under the Trump administration and this Congress will stress public-private partnerships to build toll roads. The private companies that build the roads will use tolls and congestion pricing as aggressively as they can. They will raise prices as high as the market can bear, and the gap between peak and off-peak prices will no longer be trivial.

Read:Why the tax bill is a missed opportunity to fulfill Trump’s promises on infrastructure

Congestion pricing has some positive features. Driving on public roads was never free. There were always social costs, such as congestion and air pollution, that motorists imposed on taxpayers, other road users and local residents. Car drivers were free riders. By adopting congestion pricing, motorists pay for use, especially during popular times. This approach is popular with states, as they look to life without the Trust Fund and meeting transportation needs with much less federal help.

Congestion pricing nudges people to drive at different times, use alternative means — such as public transit and carpooling — and to telecommute. At its best, makes people to think seriously about their work, housing and transportation choices.

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But there are negatives to relying more on congestion pricing and higher tolls.

As drivers, we must accept that private operators’ profit motives and responsibility to their shareholders doesn’t always align with the public interest. For example, Indiana had to pay the private operators of a toll road almost a half-million dollars to waive tolls during a flood evacuation.

Congestion pricing is an onerous tax on lower-income motorists because it constitutes a larger portion of their transport dollars. Public transport may be an unattractive or inconvenient option. Just ask Virginia commuters fed up with the frequent failures of Washington, D.C.’s subway system that has lost 135,000 daily riders in the last few years.

The wealthier have a greater ability to either move closer to work or to change their hours of work to avoid the steepest costs. Congestion pricing tends to make high-density neighborhoods close to good public transport even more attractive, leading to gentrification. Those with lower incomes are pushed further away, making them even more vulnerable to steep congestion pricing.

So congestion pricing nudges but it also redistributes. It is regressive if it comes without massive investments in public transportation and more forceful land-use planning. And these face their own obstacles. A $5.6 billion, 16-mile light-rail system first proposed for Washington’s Maryland suburbs in 1994 was finally approved after numerous lawsuits and appeals in 2016. Construction on what is known as the Purple Line began this August, but lawsuits are still pending and the project may miss its 2022 start date.

Read:Focus on better roads, not building Washington, D.C.’s Purple Line

Regardless of these drawbacks, congestion pricing is the future of commuting in the U.S. We better get used to paying more to drive on public highways at peak times.

John Rennie Short is a professor in the School of Public Policy at the, University of Maryland Baltimore County. Follow him on Twitter @JohnRennieShort

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