Bumper to Bumper | Cable barriers going up in 8 counties

Q: Snohomish County resident Ron Adrianse has noticed, while traveling on Interstate 5 north of Seattle, signs that proclaim that median cable barriers currently under construction "save lives."

Those signs got him to wondering how many people are injured or killed on average annually as a result of vehicles crossing the freeway median and colliding with oncoming traffic, and how much it costs to install those median cable barriers.

A: Since I-5 runs the length of the West Coast, from Canada to Mexico, compiling numbers of injuries and deaths would be a mammoth project, says Travis Phelps, a spokesman for this state's Department of Transportation (DOT).

But in general, he says, his department thinks cable barriers help keep motorists safe. And that's why the state installs them, in addition to guardrails or concrete barriers.

But before installing barriers in a median, Phelps says DOT engineers consider whether a barrier would improve safety, and which type of barrier might work best for that site. The department considers the site's accident history, traffic volumes and speed, the road grade, and how much median and shoulder space is available.

Phelps said the state is in the process of installing about 70 miles of cable guardrail in eight counties and on nine separate highways across the state. That work — it's an $8.8 million project — is being paid for with gas-tax money from the 2005 Legislative Transportation Funding Package.

Details about where the state is installing cable guardrail are online at www.wsdot.wa.gov/projects/cablebarrier.

Q: Traffic questions are not always a matter of life or death. Sometimes questions are just a matter of curiosity.

Bellevue resident Diana Sigalla is curious about all the little colored flags she's spotted around the area. Each flag, she says, appears to be about a foot-high wire with a small, colored plastic square on the top. "They seem to come in all colors and sometimes there are just a few here and there."

At other times, there are whole fields of them, she said, such as the cluster she spotted near an onramp to Highway 518 in the Burien area.

A: Matt Clifton, a spokesman for Puget Sound Energy, says such flags are often used to mark underground utility lines.

An independent utility-locator service uses red flags to mark underground electric utilities; yellow for natural-gas or oil lines; orange for communications lines, such as cable TV, fiber optics and telephone; blue for water lines; and green for sewer lines.

Such markers are often used in construction projects. Sometimes you might see spray-painted markings. But little flags are frequently used in areas where the ground is unstable or where water might wash paint away.

Bumper soapbox

Dean Norton of Portland says it sure would be helpful if signs posted for northbound I-5 traffic approaching downtown Seattle were placed so that drivers had more warning before reaching the start of express lanes.

Access to the express lanes when headed north is on the left side of the freeway. "You have traffic moving into the left lane to take the express lanes, as well as other people moving into the left lane trying to take the Seneca [Street] exit," Norton pointed out. "It's not until you approach the actual exit for the express lanes do you have [a] sign that warns you whether or not the express lanes are open/closed.

"If the express lanes are closed, then you have to quickly try and merge back into the right lanes, as the left lane ends."

Norton suggests placing the open/closed signs several miles ahead of the exit.