Car pool and bus lanes are cheap and might be worth a second, long-term chance, officials said in the fallout of the six-day Interstate Bridge closure that ended early Monday.
The evaporation of traffic also raised questions about assumptions that the region should move quickly to build more expensive light rail, freeway lanes or a third Columbia River bridge to handle the population boom in Clark County, Wash.
Planners had warned of traffic jams as long as 40 miles. Businesses formed van, bus and car pool service, and transit agencies offered increased or free service. Print and broadcast media went to great lengths to report about the closure.
The closure of the northbound span provided the first test of express lanes on Portland-area freeways in more than 15 years as well as the first-ever trial of commuter rail.
"I think that this has shown that there is an incredible amount of capacity in our existing system, should people decide to use it in a different way than they're using it today," said Thayer K. Rorabaugh, Vancouver's traffic engineer.
Transportation department leaders, exhausted after long hours of managing the bridge closure, hesitated to draw too many early conclusions about the startling success with traffic. They plan to spend the next several days crunching numbers so they can begin to understand the commuting experience of the past week.
Political leaders were more willing to draw more sweeping conclusions.
"The big lesson here is, we don't need massive and costly road capital projects," Gov. John Kitzhaber said at a news conference Monday announcing the bridge's reopening.
"This is a victory for transit. It is a glimpse of what could be done to make the roads work better if we provide transit alternatives."
Vancouver Mayor Royce E. Pollard said he sees a need to look for alternatives to adding more lanes for cars. "This community's proved we can change the way people think about cars," he said.
Some predict a surge in public and political interest in freeway bus and car pool lanes, which often are called diamond lanes because of the diamond markings on the pavement.
The state recorded in the range of 3,000 new car poolers during rush hours on I-5 and I-205, enough to absorb about 20 percent of the traffic drop recorded on the Interstate Bridge. The car pool numbers were typically double the combined count of new riders on Clark County's C-Tran buses and the free Amtrak commuter trains.
The popularity of car pooling is explained partly by the region's increasingly scattered job base. Only 16 percent of Clark County residents who commute across the Columbia River work in downtown Portland. The rest are spread out throughout the metropolitan area, typically in areas poorly served by transit.
Tektronix Inc. is keeping in service a fourth van pool added for the bridge closure because of its popularity with commuters. About 300 people a day took the Freightliner Corp. shuttle from Clark County to Swan Island -- nearly 9 percent of the company's work force of about 3,500.
"I guess we've learned that there's definitely an interest in people using some sort of mass transit," said Harry Smith, who helped coordinate Freightliner's transportation alternatives.
The temporary express lanes gave car poolers and bus riders an advantage they don't ordinarily enjoy on congested I-5 and busy I-205. One reason they worked well was heavy enforcement by police.
But after the bridge reopening, highway workers began removing the diamond lanes from the freeways.
"I think they'll be back before too long," Portland City Commissioner Charlie Hales said.
Car pool lanes have been used in the Portland area only once, and that was on the Banfield Freeway (I-84) between 1975 and 1982.
The Amtrak commuter rail service operated at far less than capacity, perhaps because of the isolated location of the Amtrak station in Vancouver and the availability of C-Tran service from suburban Clark County locations. The fare-free Amtrak shuttle averaged 1,335 riders a day, at a cost to Oregon and Washington of $15,000 a day.
The analysis of the commuter rail service will be watched closely by planners who are examining the feasibility of using freight train tracks for passenger service in several parts of the metropolitan area.
They'll get good readings from riders such as Dan Martin, a sales engineer for Halbar-RTS in Tigard, who rode the train daily from Vancouver. Martin suggested a $5 or $6 round-trip fare would be reasonable.
One big question for the future is whether a system of imposing rush-hour tolls on travel to reduce congestion would gain political acceptance in the region.
Advocates argue that people will continue to clog roads as long as the system does not offer incentives to change their travel habits. Metro is studying whether to test congestion pricing in the Portland area.
Russell Hancock is vice president of the Bay Area Council, a San Francisco business-backed group that is active in transportation issues. He said the six-week closure of the Bay Bridge after the 1989 Loma Prieta earthquake created a huge demand for Bay Area Rapid Transit and temporary ferry service. But most people returned to their cars once the bridge reopened.
"Once things go back to normal, people take their cars," said Hancock, an advocate of congestion pricing. "People are willing to sit in traffic. They complain about it, but they are not willing to do anything about it."
Holley Gilbert Corum and Don Hamilton of The Oregonian Staff contributed to this story.