No parking within 30 feet: That's about two car lengths

The posted signs warn: "No parking within 30 feet." But how is a motorist to judge that distance — and where should it begin and end?

Jeff Aimar of Seattle says that concern has bugged him for about three decades. And why, he wonders, is the parking restriction, most often near corners, listed in feet with a compass direction rather than painted in red on the curbing?

"I wonder how many people can accurately gauge 30 feet from the corner," Aimar said. Steve Erickson of Seattle recently expressed nearly the same concern.

Both Aimar and Erickson suggested that painting the curb might be the simplest solution.

"I know that painting curbs requires periodic maintenance. However new-technology paints are probably available that last many years," Aimar said. "If curb painting is simply not an option, how about a second sign at the 30-foot point that says 'No Parking Between Signs'?" Aimar said.

Answer: Rob Spillar, the Seattle Department of Transportation's traffic-management director, says both Washington state and Seattle law are clear that vehicles may not park within 30 feet of a stop sign (or within 20 feet of a crosswalk or 15 feet of a fire hydrant).

"The basic rule of thumb for estimating 30 feet is to leave approximately two car lengths between the front of your car and the stop sign or the curb of the intersecting street," Spillar said.

That distance, he said, is necessary to ensure that visibility is maintained for drivers approaching intersections, to allow them to see cars coming toward them from other directions and to allow them to be seen by other drivers.

Seattle's transportation department does not mark curbs to indicate the 30-foot zone. Spillar said doing so for the more than 9,000 stop-sign locations "would pose a significant challenge from both a funding and maintenance perspective."

The city, Spillar said, relies on drivers to use common sense and leave a generous distance, and he thinks most drivers are able to estimate 30 feet.

John Mahlum of Seattle says he's perplexed by a traffic light in the Interbay area. During rush hours, the signal at West Dravus Street and 15th Avenue West operates as flashing red lights. At other times when traffic is lighter, it's a regular three-color stoplight. At the west end of the Dravus bridge across the train tracks, the light at 21st Avenue West operates as a stoplight all the time.

"This arrangement is puzzling," he said, because when the system switches to red-yellow-green mode during off-peak hours, lengthened signal cycles produce long lines that often must wait for little crossing traffic. The long lines also block cars approaching Dravus from intersections and parking lots.

"I am one of those who fume at such a needless waste of time," he said. "Why can't each of these intersections operate as blinker signals all the time?"

Answer: The intersection of West Dravus Street and 15th Avenue West used to run in a typical signal operation at all times, including rush hours, said Spillar of Seattle's Department of Transportation. However, engineers found that was causing rush-hour backups.

The Seattle transportation department staffers met with community members, Spillar said, and agreed to try flashing red lights at the intersection during the busiest periods.

Contrary to Mahlum's experience, Spillar said traffic is flowing more smoothly than before. "This change has been in place and working well for several years."

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