At the tail end of a three-hour drive from upstate New York to Boston, Professor José Holguín-Veras stared morosely through his windshield at the signs of a transportation apocalypse. “I’m surrounded by trucks and nothing is moving,” he grumped into his cellphone. “This is what the future looks like.”

Then he couldn’t help but chuckle at the irony of running late for his presentation at the Massachusetts Institute of Technology on the subject of — you guessed it — traffic jams.

But not just any traffic jams. Holguín-Veras’s particular expertise is understanding why our favorite means of avoiding traffic — online shopping — is making gridlock worse. After all, when we buy on the net and virtualize our carts, aren’t we all avoiding driving? Shouldn’t that make traffic better?

In a word: No, Holguín-Veras says. We create a truck trip each time we click that enticingly convenient “Buy” icon. And we click that button a lot. The old way of shopping lists and a single car trip to the mall or the market to make multiple purchases is fading away. Now we are lured by unlimited free shipping — and next-day and same-day delivery — to impulse-buy one item at a time, spread out over many days and many separate truck deliveries.

Holguín-Veras, director of the Center of Excellence for Sustainable Urban Freight Systems at New York’s Rensselaer Polytechnic Institute, says our city streets and parking resources are being swamped by this new retail reality. Cities simply are not designed to handle the daily tidal wave of deliveries produced by our have-it-now online economy.

“If we all keep on buying as we are year after year, without regard to the impact,” he predicts, “we are doomed.”

The data is stark. The number of freight deliveries per person in America has doubled over the last decade, Holguín-Veras says, with almost all of that growth attributable to internet buying. From 1963 to 2009, the U.S. per capita rate of deliveries of all kinds of freight — commercial and residential — remained remarkably stable, declining a small fraction over those five decades to .12 daily deliveries per American. That’s slightly over one freight trip a day for every ten people in the country.

Between 2009 and 2017, that figure rose to an average of 2.5 freight trips for every ten Americans. At current growth rates, that number will double again by 2023. This time of year, the holiday shopping rush is already double the average rate of deliveries per person. “This is unsustainable,” says Holguín-Veras. “It will only get worse. There is literally no room for all those trucks.”

The aggravating, costly and polluting effects of all these deliveries on traffic congestion already are being felt in medium and large cities across the country. University of Washington (UW) researchers in Seattle, the birthplace of both Amazon and United Parcel Service (UPS), have found that about half of the trucks making deliveries downtown are forced to park in unauthorized spots — blocking alleys, double parking on already congested streets or parking in bike lanes and other no-parking zones.

Apartment and office towers are particular chokepoints because they receive large numbers of daily deliveries from Amazon and other retailers. Yet they typically have no loading docks or reserved parking for the UPS, Federal Express and U.S. Postal Service delivery trucks streaming to their curb-fronts.

According to Anne Goodchild, director of UW’s Supply Chain Transportation and Logistics Center in Seattle, research shows about 80–90% of delivery drivers’ time in urban areas is spent on foot, searching for the right apartment or office, riding up and down elevators and haggling at reception desks where employees don’t want to be responsible for the flood of boxes. And all the while, their trucks are blocking lanes and slowing traffic.

Logistics researchers used to worry about the first and last mile as the most problematic and least efficient part of freight movement. “Now,” Goodchild says, “we worry about the last 50 feet.”

The result: trucks, which represent 7% of total traffic, account for 28% of the nation’s congestion, according to the latest Urban Mobility Scorecard from the Texas A&M University Transportation Institute. That cost the economy about $160 billion in 2014 in terms of fuel waste, pollution and lost time, up 9% since 2009. During that same span, the amount of time Americans spent collectively stuck in traffic rose 600 million hours while fuel waste due to congestion rose 700 million gallons. Convenience has its price: other studies suggest emissions from traffic congestion account for 2,200 premature deaths and 30% of greenhouse gas emissions from cars and trucks.

The good news is that there are cures for the unintended consequences of our have-it-now online economy that are being tested or have already been adopted. And everyone can play a part, from retailers to carriers to online shoppers.

Holguín-Veras’ favorite fix is to time-shift deliveries so that they occur during hours when traffic is light even in downtown areas. Domino’s Pizza is one of a minority of companies that has taken this approach, sending its franchise supply trucks out for graveyard shift deliveries long before their pizza parlors open for business. Drivers have keys and stock the stores like pizza elves in the night. Delivery drives take a fraction of the time they would need during rush hour.

Holguín-Veras’ study of truck traffic in New York shows that making such time shifts systematically would cut freight-related emissions by 60% while removing trucks from rush-hour congested streets. About 30% of businesses surveyed would love to have that sort of delivery, Holguín-Veras says, but few are given that option.

Goodchild, meanwhile, is working with delivery companies, online retailers and the City of Seattle on several pilot studies intended to solve that “last 50 feet” problem. Her team is measuring the effect of installing street-level lockers so an entire building’s daily package deliveries can be quickly dropped off in one place rather than forcing drivers to wander big office and apartment towers. This could dramatically cut the time trucks double park, prevent porch piracy and also pair nicely with time-shifted deliveries.

Another pilot study near Seattle’s iconic — and nightmarishly congested — Pike Place Market has UPS deploying electric bikes with trailers capable of carrying 400 pounds of freight. A single big-rig trailer is given precious parking space near the market every day. Inside are preloaded bike trailers (they look like cute mini-versions of the familiar brown delivery trucks), which the UPS bikes move over bike lanes and sidewalks without slowing down street traffic. If the time and cost of two-wheel deliveries are as favorable as expected, UPS plans to deploy this system nationwide.

Goodchild says consumers can do their part, too, by easing up on the single-item same-day and one-day deliveries when buying online. Instead, she says, make a list and purchase multiple items at a time, then choose the shipping option that allows sufficient time for those items to be combined and delivered in one shipment.

Now for the bad news: At the moment, there are few compelling financial reasons for companies or consumers to make any of these traffic-fixing changes. In fact, the incentives are so out-of-whack that online retailers are willing to lose money on free shipping just to keep up with the competition. If Amazon offers it, so must Walmart, Nordstrom, Macy’s and Target. The true cost of free shipping and peak-hour deliveries — bad traffic, more smog, greenhouse gas emissions, wasted resources — is not reflected in our online shopping carts.

It will take an unprecedented level of cooperation between the private sector, government, labor and consumers to fix this mess with meaningful financial incentives — and leadership at the top that makes it a national priority. We can still have our convenience with a few tweaks that, in the long run, will be better for our economy, our commutes, our health and our climate.

Until then, every time you gripe about city traffic or your frustrating commute, just remember it’s your online shopping traffic that’s really driving you crazy.

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