We're told to watch out for drunken drivers. But a study in nine California cities – including Modesto, Fresno and San Rafael – suggests there may be more drivers out there impaired by drugs.

The state Office of Traffic Safety study found 14 percent of drivers on Friday and Saturday nights had drugs in their systems, twice as many as those with alcohol.

The study was unusual: Study leaders motioned drivers over to a parking lot and asked if they would be willing to participate. Seventy-seven percent said yes. They were told the findings would not be used against them. Impaired drivers were asked, however, to call someone to pick them up after the test.

"These results reinforce our belief that driving after consuming potentially impairing drugs is a serious and growing problem," said Chris Murphy, California director of traffic safety.

The drugs ranged from marijuana to prescribed medicine.

Murphy and other safety officials want more research and funding on drug-impaired driving. It's harder to detect than drunken driving, they say, and requires special test equipment as well as officer training.

Super Pedestrian

The city has launched an interesting crosswalk experiment on Stockton Boulevard and Sherman Way near the UCD Medical Center. Officials are giving pedestrians the power to stop cars – kind of like Superman – with a pedestrian-controlled light.

When a pedestrian wants to cross Stockton, he hits a button which sets off an overhead light that's yellow for a few seconds, then turns red. Cars must stop, allowing the pedestrian to cross. The light stays red a handful of seconds, then reverts to green.

The signal costs $85,000, far less than the $300,000 cost for a regular signal light. If it works, the city may try it elsewhere.

Bike trail additions

Progress continues on plans for a bike and recreation trail on the south side of the American River from downtown to California State University, Sacramento.

A section is already built near Richards Boulevard downtown. Next week, the state will grant the city funds to add a half-mile section in Sutter's Landing Park. And the city is beginning design work on the section that will run behind the River Park neighborhood between Sutter's Landing and Sacramento State.

That portion could be built in 2014, Councilman Steve Cohn said.

Most of it would be at the base of the levee on the river side, but part of it likely will have to be built on top of the levee, overlooking 29 backyards at the west end of River Park. That's because there isn't room there for a trail at the levee base, Cohn said. The city will gather community input next year during environmental review.

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