SHANGHAI'S traffic is getting worse: It's moving slower, jams are taking longer to untangle, the din of horns is getting louder, and, of course, it's getting more dangerous for everyone on four wheels, two wheels or two legs.

Critics say Shanghai traffic makes the streets of Bangkok and Manila look good - that may be an exaggeration - but with 5,000 cars added every month to a road system that isn't expanding, it won't be long before the city holds some disturbing records. One in five households owns a private car and 1.7 million license plates have been issued in Shanghai, according to police.

There's endless talk and not much improvement - it's a car-centered city and pedestrians and bicyclists don't get priority. Perhaps only a mass brain-transplant would help.

In the meantime, Weng Denghai, head of the traffic police in Zhabei District, is doing his best to at least get the cars flowing smoother and faster. Some of his ideas have been applied at more than 90 downtown intersections around the city.

Once the Shanghai native was assigned to busy intersections, wearing white gloves, making sweeping gestures and blowing a whistle. Now, though he does go on patrol, the 52-year-old spends more time poring over traffic flow diagrams, using a timer and trying to change traffic patterns.

"They call me 'magic' on the road," said Wang, speaking confidently, with a cigarette cradled between two fingers. "For the past 20 years, I have been trying to break the habitual mindset of most drivers and improve traffic flow.

"I can handle the traffic but I cannot stop the increasing number of vehicles on the roads. I hope to manage them in better ways," he said, acknowledging that road widening isn't feasible in many areas.

Drawing a line

"It's hard to watch traffic jams every day," he said, gazing down at the intersection of Tianmu and Wuzhen roads, one of the most congested in the city, from his office in downtown Zhabei District.

He used to walk to the crossroads and stare at the lanes for hours while trying to think of a solution.

Then one day last December, Wang carried a can of white paint and a roller brush to the intersection and painted a new stop line around 60 meters behind the original one on the four lanes of Tianmu Road that go eastwards. Of the four lanes, one is for U-turns, two are for straight-ahead traffic and the other is for vehicles turning left.

When the left turn signal is green, the cars turning left can use all four lanes between the new and old stop lines, thus enabling traffic to move faster. The same principle applies when vehicles going straight or making a U-turn have a green light. A traffic officer is on hand to guide vehicles at the intersection.

Wang said the four lanes technically become 12 and that his idea has increased capacity at crossroads by as much as 300 percent, adding rush periods that once lasted as long as two hours are shortened to 30 minutes.

"It's like a water reservoir. Once the gate is lifted, the vehicles can go faster," Wang said.

"Drivers have told me it's a brilliant idea."

It's the first time such a method was used in China and it has been applied citywide at around 90 key intersections, all downtown. It's especially effective at intersections near the off-ramps of elevated roads.

This is not Wang's only idea that has changed how traffic flows in the city.

Back in 1988-89, about four years after Wang joined the traffic department, he extended the left-turn lane into the middle of the intersection. It allowed more vehicles to line up and make the turn move quickly once the light turned green and is still used at numerous crossroads in Shanghai.

"Being an (Thomas) Edison is not easy," said Wang, with a smile.

In 2007, Wang and a team from Tongji University set up traffic lights on the elevated traffic circle on Tianmu Road in Zhabei. The signals are timed according to traffic volume and direction.

"Maybe I was born to be a traffic police officer and I know what it means to spend my career handling the traffic," he said.

Wang attended a technical school in Shanghai and after graduation he joined the army in an artillery division. He spent his early 20s in an army camp in northern China during the 1970s when the tumult of the "cultural revolution" (1966-76) was near an end. He became one of his unit's best gunners.

"The experience gave me a strong sense of space, trajectory and calculation," said Wang, who joined the traffic department after leaving the army.

Reflecting on how things have changed from 10 years ago, Wang said that even though it may not seem like it, drivers are somewhat more conscientious of the rules these days.

"Back then one car could scare off a bunch of cops," said Wang, noting that drivers "just did what they wanted."

He said there is still a long way to go despite the improvement and talks about a trip he took to the United States several years ago.

"Drivers would wait and give way to pedestrians even if there was no traffic light," Wang said. "No one seemed to be in a hurry. It's hard to imagine that happening here.

"Of course we have more people in Shanghai, but as citizens it's a lesson we should learn."

As for the challenges facing the city's road network, Wang said he has no illusions about how difficult the job is.

Every month, about 5,000 more cars appear on city streets. If they were lined up they would stretch from Hongqiao International Airport to the downtown Yan'an Road Tunnel, he said.

"In four months, the city would have to build another 15-kilometer stretch of Yan'an Elevated Road to handle that volume," said Wang, who enjoys playing sports such as badminton and doing amateur magic tricks in his spare time.

But prohibitive costs make building more roads and street-widening projects unfeasible. Removing one wire pole for road enlargement costs around 150,000 yuan (US$23,155) and adding one lane can cost millions of yuan, he said.

"Imagine the cost of adding two lanes or more, then add the costs of house demolition and road construction. It would easily cost billions of yuan," he said.

Meanwhile, traffic is moving more slowly downtown during morning and evening rush hours. A recent study found that the morning rush hour speed inside the Inner Ring Road was 17.44 kilometers per hour in 2004 compared to 16 kph today. During the evening rush hour, the average speed dropped from 15.45 kph to 15 kph.

More than 7,000 traffic police citywide deal with 500,000 traffic violation cases each month, which is probably only a fraction of the transgressions that occur.

Meanwhile, Wang said he's still thinking of new ways to better manage traffic and find a little quiet time between shifts.

"It's important to find inner peace in my job," said Wang, who was gearing up for a night time street patrol.