'No Shoulder Driving' means exactly what signs state

Q: Why does King County (and possibly other local jurisdictions) use the ambiguous phrase "No Shoulder Driving" to prohibit a tempting swing around left-turning vehicles on some two-lane roads (Juanita Drive in Kenmore and Kirkland, for example) instead of the more direct "No Passing on Right?"

A: King County public-affairs guy Tim O'Leary checked with the roads division for an answer, and here's what he got: A "No Passing on Right" sign is used only when there's a second lane someone could actually use to pass in.

Because you're talking about a two-lane road, the "No Shoulder Driving" sign is used. Shoulders are not made for passing, and the sign is far from ambiguous, O'Leary said. If there's a shoulder, and the sign says no shoulder driving, you're supposed to stay out of the shoulder unless it's an emergency.

Of course, if you feel you were ticketed wrongly or that the sign is truly confusing, you can always take a picture and contest your ticket.

Q: Do you know of any movement to make the car-pool lanes on Highway 520 consistent with those of the other freeways in this state (where the car-pool lane is on the left side and not the right)? I don't understand the state Department of Transportation setting up an inconsistent policy like this.

A: First, the car-pool lane along Highway 520 was placed on the outside, or right side of the road, because of tight space west of Interstate 405. The three-person-plus car-pool lane between I-405 and the 520 floating bridge is actually a converted roadway shoulder, explained Melanie Coon, state DOT spokeswoman. The shoulder was converted so that buses could bypass the toll booths back in the 1970s, and technically, it's a substandard lane (it's very narrow, has no shoulder and many merge points).

The car-pool lane could not be moved to the inside without bringing the outer lane up to standard, Coon said.

Here's why: The surface of the outer lane is less thick than the other two lanes and couldn't handle the higher volumes of traffic from a regular lane, Coon explained. Even though car-pool lanes handle buses, they still carry less weight than the other lanes, she said.

Also, because of all the freeway bus stops along 520, it would be difficult for transit to drive on the inside lane.

East of I-405, the 520 diamond lanes are kept on the right for consistency. Coon said the DOT wants to update the entire system and move the diamond lanes to the inside with a rebuild of the floating bridge, but the lanes won't change until then. That project remains mostly unfunded.

You can check out what's being considered by going to: www.wsdot.wa.gov/projects/Translake/

Early warning

• ISSAQUAH — One lane of I-90 in each direction through Issaquah will be closed weekdays next week during daytime hours.

• RENTON — Weather permitting, the exit from southbound I-405 to southbound Highway 167 will be closed from 10 tonight to noon tomorrow for paving operations.

• BELLEVUE — Freeway ramps adjacent to the Northeast Eighth Street overpass at I-405 will be closed nights next week from Monday night to Friday morning. Closures will begin at 9 p.m. and last until 6 a.m.

• HIGHWAY 520 — There will be frequent single-lane and shoulder closures on eastbound Highway 520 on the Evergreen Point Floating Bridge from 10:30 p.m. to 5 a.m. on weeknights next week.

• REDMOND — On weekdays next week from 9 a.m. to 3:30 p.m., sections of Woodinville-Redmond Road (Highway 202) north of downtown will be reduced to one lane with flaggers directing traffic.

Natalie Singer: 206-464-2704 or nsinger@seattletimes.com