If you drive to work, you might start to wonder–as you’re sitting in bumper-to-bumper traffic, slowly watching minutes of your life tick by on your dashboard–why so many Americans subject themselves to car commuting every day. And while the answer is obviously complicated and has a lot to do with urban design, one part is pretty straightforward: Most employers offer free parking, and that makes people more likely to drive.
In a new study on commuters in Washington, D.C., researchers found that even when a company offered employees bus or subway passes, or incentives to ride a bike, those benefits didn’t make much difference if people also had the choice of free parking.
“There have been a lot of studies that indicated that benefits for public transportation or biking are effective on their own,” says Andrea Hamre, a PhD student at Virgina Tech, who worked on the new research with Ralph Buehler, an associate professor in urban affairs and planning. “But the positive effect they seem to have is rendered insignificant–it seems to go away–in the presence of car parking.”
Put another way, if your employer gives you a subway pass, and nothing else, you’ll probably get on the train. But if you have the option to park for free, you’ll almost definitely choose the car. In the D.C. study, people were actually more likely to drive if they had a mix of benefits, including public transit or biking incentives, than if they had no transportation benefits at all.
The researchers are gathering more data now to measure the impact of D.C.’s new bikeshare program, and new benefits like parking “cash-out” programs that pay employees if they choose not to use a parking space. They also plan to begin looking at other areas, starting with Atlanta. But it seems likely that the results will be similar: Research has been pointing to the fact that free parking makes people drive for a long time.
In a much earlier study, researchers found that when an employer in L.A. stopped paying for free parking, 98% of employees stopped driving.
“Policymakers interested in reducing commuting by driving should consider reducing the supply of free parking,” says Hamre. One place to start, perhaps: the tax code, which lets employers give up to $250 a month in pre-tax dollars for a parking spot.