Donald Shoup may be known as a guru of smart parking policy, but even he has found a few surprises in the data collected so far from SFpark.
“The biggest surprise I got was that prices went up and down, but overall, they stayed the same. The average price actually declined by 1 percent,” said Shoup, professor of urban planning at UCLA and author of The High Cost of Free Parking, the bible of modern parking policy. “That surprised everybody. People thought it was just a way to jack up prices, but the city specifically said, ‘We are going to set prices according to this principle.'”
SFpark, which uses “smart meters” and ground sensors to measure parking occupancy and adjust prices accordingly, is providing valuable lessons for San Francisco and cities around the world that want to reduce the amount of time drivers spend cruising the streets for a parking space.
The growing body of data collected from the program is shedding more light on the complexities of parking demand. But overall, Shoup says, it’s providing hard evidence that raising and lowering meter prices is an effective way to keep enough parking spots available for drivers who need them — and to help ensure too many spots don’t sit empty.
Keeping, say, one parking spot open on every block “will make the transportation work best — it’ll reduce cruising, speed up buses, reduce air pollution,” said Shoup. “It’s easy to explain [a goal] like that — we’re aiming at what you want to see.”
In a recent report [PDF] published in the Journal of the American Planning Association, Shoup and UCLA doctoral student Gregory Pierce explain that since SFpark managers began adjusting meter prices in August of 2011, the “elasticity” of parking demand — the degree to which price changes affect parking occupancy — has varied across different locations and times of day (due to different trip purposes, they surmise), and that drivers changed their behavior most profoundly after the second price adjustment, possibly due to a spike in awareness of the program. As prices have been refined, elasticity has declined.
Prices appeared to have the lowest impacts in highly residential neighborhoods like the Mission and the Marina, while retail districts like Fisherman’s Wharf and the Fillmore saw the most drastic adjustments to new prices, according to the report.