In a southbound view, commuters on the Md. Route 175 eastbound interchange barely move, waiting to exit onto northbound I-95, whose traffic crawls toward Md. Route 100. (Karl Merton Ferron, Baltimore Sun / May 1, 2013)

In the stop-and-go world of Baltimore-area traffic, there's a lot more braking than commuters and transportation officials would like.

Take Russell Allen, a Federal Hill resident who gets in his silver Ford Edge every weekday morning before 7:30 and steers south toward Fort Meade and the region's biggest bottleneck: Baltimore-Washington Parkway and Route 175.

The trip starts fine. But around Route 100, Allen's windshield relfects a dazzling array of red taillights. "And it stays that way until I get to work — four miles and 20 minutes later," said Allen, 52, who works for the Army.

Going in the opposite direction in late afternoon is even more excruciating, as northbound commuters try to merge with drivers who opted to leave work by Route 32, slightly more than two miles south. The resulting mixing bowl creates a daily backup that averages nearly 10 miles, according to the Baltimore Metropolitan Council.

Now that the General Assembly has approved a gas tax hike expected to generate $4.4 billion over the next six years, transportation officials see an opportunity to address some of the region's chronic trouble spots. They're planning to modify dangerous 1960s-style cloverleaf exchanges such as one at Harford Road and the Beltway — the second-worst bottleneck — and to make other localized remedies that cost a few million dollars.

But fixing some problems — like the B-W Parkway — will happen "when we make cars that fly," deadpanned John Powell Jr., Howard County's transportation chief.

For area travelers, that will mean more lost time and money. Congestion costs the average driver $908 annually in lost time and wasted fuel, according to a study by the Texas Transportation Institute. The same beleaguered motorist idles away 41 hours — a week's vacation — looking at the bumpers ahead.

"You don't know how much time to leave when you have an appointment. You can be early, be late or be on time," said Linda Alvarez, a home health aide from Towson who was filling her travel mug with coffee at a White Marsh convenience store before tackling the Interstate 95 construction zone. "You need a crystal ball."

The Baltimore region's top 10 bottlenecks come in all varieties. Half are on the Beltway and two are on I-95 north of the city, where thousands of commuters pour in from Harford and Cecil counties each day. Another trouble spot develops on I-95 in Harford County during November and December, as holiday travelers head home after visits with family and friends. And, in a twist, two of the congestion culprits are byproducts of construction aimed at making roads more efficient and safer.

As the region continues to grow — government estimates say that by 2040 the population will increase 38 percent and employment will rise 47 percent — officials will be hard-pressed to ease the congestion. Planning and paying for that future is moving as slowly as the traffic.

"There have been no major projects to alleviate the situation, and projects take a long time to get off the ground," said Todd Lange, the Baltimore Metropolitan Council's director of transportation planning. Four times a year, the council, which advises the region's governments on transportation, calculates the region's top 10 congestion magnets using a formula that takes into account the number of daily backups, the average duration and the average length.

"With new money comes a lot of expectations," Lange said. "There's a lot of needs and a lot of eyes watching what's going to happen over the next few years. It's time to focus."

Armed with GPS units, smartphone traffic apps and radio reports, drivers do the best they can. Government agencies such as the State Highway Administration and Maryland Transportation Authority pass along information from traffic cameras and through email and text messages, and dispatch tow trucks to clear breakdowns and accidents as quickly as possible.

That only goes so far.

"We're surrounded," said Charlie Alves, director of route sales for Baltimore's H&S Bakery, which has about 100 drivers who log a total of 2 million miles annually. "We try to find the back roads to meet our deadlines, but it is a major inconvenience. The traffic by itself is bad, and then you run into a fender-bender and — hello? — it's over."

Louis Campion, president of the Maryland Motor Truck Association, said congestion delays hit haulers, especially independent drivers, hard. The Texas Transportation Institute estimates the average cost of congestion for truckers at $88 an hour.

"One guy who runs his own truck is building business around moving loads, sometimes multiple loads, in a single day. You force him to sit in traffic, and he isn't making money. He's losing money," Campion said.

Truck drivers also risk running out of time. Federal safety regulations limit daily driving to 11 hours and no more than 82 hours within a seven-day period.

"With congestion, you can run out the clock and end up with truck drivers stuck on the shoulder of the road, which is not what anybody really wants," Campion said.

By all accounts, the Baltimore region's traffic congestion isn't as bad as in Washington or Los Angeles. In its score card released last week, INRIX, a traffic data collection company, ranked the region No. 17, without a single road in the Top 100.