The idea behind high-occupancy toll lanes is pretty simple: Carpoolers ride free, but single riders pay a toll rate set by the principles of supply and demand. The more crowded the lane becomes, the more expensive the toll.
Tolls that automatically adjust to traffic do help pay for the roads they are on, but their main purpose is to reduce congestion on highways, said Neil Gray, director of governmental affairs for the International Bridge, Tunnel and Turnpike Association, an industry group.
But now many of the companies and agencies that run toll roads are discovering that even high prices sometimes aren’t enough to keep traffic flowing as fast as they would like.
In many cases, they’re looking for new ways to satisfy demand, or even drive it down, without building even more lanes.
“At this point, we may be a victim of our own success in terms of the amount of people and the volume of the vehicles using it,” said Rick Jager, a spokesman for Los Angeles County’s Metro, which operates two toll roads in the area. “But that’s the beauty of the system. You can monitor it and adjust it to better manage that infrastructure.”
Driving the agency’s 11-mile Harbor Freeway toll lanes at peak times -- typically Tuesday and Wednesday mornings, between 7 a.m. and 8 a.m. -- can cost more than $15 (the average morning driver pays $9). But traffic is so heavy that the agency frequently closes the lanes to toll-payers for five to 15 minutes, so there’s enough room for vehicles carrying two or more people. About 65 percent of vehicles in the toll lanes carry more than one person; the remaining 35 percent to toll-lane users are solo drivers.
The toll lanes on the Harbor Freeway and the San Bernadino Freeway are little more than three years old. Metro opened the toll lanes on those highways in November 2012 and February 2013, respectively. Like similar projects in other metro areas, the new lanes were part of a larger effort to improve commutes that also involves more transit options. Metro offers $5 in toll credits to any rider who uses buses along the same route 32 times during rush hour. About 2.7 percent of its users have signed up for the program.
Still, the agency may also revisit its toll rates in the near future. Depending on traffic, Metro charges drivers 25 cents to $1.40 a mile, but its board may consider raising the top rate later this year, Jager said.
The Atlanta region is also looking for ways to curb peak traffic, because its Peach Pass toll lanes on Interstate 85 have become so popular they are running slower than they're supposed to. Traffic during peak times falls just short of the 45 mph benchmark the Georgia’s State Road and Tollway Authority is aiming for, to comply with federal standards. The six-month average is closer to 41 mph.
The 15.5-mile drive in Atlanta’s northern suburbs can reach $10 at peak travel times on weekday mornings. Since the toll road opened in October 2011, its volume has gone from around 7,000 vehicles a day now nearly 23,000.
“But we’ve received very few complaints,” said Chris Tomlinson, the agency’s executive director. Why? The toll lane is moving faster, and paying drivers notice that they are constantly passing cars in the regular lanes.
“People see value in that. But it’s still not good enough for what we want,” he said.
So the agency has three new initiatives to reduce congestion along the tolled portion of the road, especially during rush hour.
First, it launched a pilot program in February directed toward the people who drive during peak times -- and pay peak tolls -- four or five times a week. Only 30 percent of Peach Pass motorists use the lanes that many days a week. So the toll authority is exploring ways to encourage 270 of its heavy users to shift their commutes to different, less crowded times or to skip the commute altogether and work from home.
Meanwhile, the Georgia agency is adding a new program, called “Ride Transit-Earn Toll Credits,” similar to those in place in Los Angeles, for people who use public transit along its route. Participants can earn toll credits of $2 per trip, up to $10 per month, for taking the bus to get and from work. During morning commutes, buses make up only 2 percent of vehicles in the toll lanes, but they transport 26 percent of the people. But the buses are only half full, Tomlinson said, which means there’s a lot of available capacity without putting any more vehicles on the road.
The more people try using transit, the more they like it. When gas prices fell, the decrease in ridership on those buses was smaller than for other agencies, said Tomlinson, who oversees them as head of the Georgia Regional Transportation Authority. “It reminds me of being on plane in economy, with better leg room,” he said.
Finally, the agency is promoting an existing program that gives commuters who carpool or take public transit $3 a day for avoiding traveling alone in their cars. The Georgia Department of Transportation started the program, called Georgia Commute Options, in 1996 to reduce air pollution in the Atlanta area. Starting in May, the toll agency will match those cash incentives with toll credits.
Keeping traffic moving quickly on tolled lanes requires other basic services. Transurban, a company that operates tolled lanes in Northern Virginia, for example, dispatches its own crews to clear debris and help motorists with vehicle problems. It can also change speed limits to react to hazardous conditions and use electronic signs to warn motorists of delays ahead of time.
So far, though, Transurban, has not yet run into the congestion in Atlanta and Los Angeles. It first opened its toll lanes on the Beltway in 2012 and on Interstate 95 in December. The average speed along both roads is 65 mph.