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Frequently Asked Questions Archive

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Below are the most frequently asked questions fielded by our Communications staff. Click on the question or topic to find the answer.

HOT Lanes     

HOV Lanes    

Freeway Signs    

Travel Times 


Winter Driving 

Mountain Passes 

Ramp Meters 

Signal Timing 





HOT Lanes

Don't you think it would make more sense to charge more for using the HOV lane if the normal lanes were clear than if the traffic was heavy?

A. The tolls for the HOT lanes will increase depending on the level of traffic needed to make State Route 167 run more efficiently. For example, the idea is to increase the number of vehicles in the carpool lane when there is unused space. When congestion begins to build in the general purpose lanes, space in the HOV frees up and the demand for that space increases. In this case, WSDOT offers a fee for the commodity of space. The greater the demand, the higher the tolling price drivers will see. This aims to discourage more solo drivers from using the HOT lanes and allows WSDOT to maintain free-flowing speeds for carpools, transit and buses, which never pay a toll. 
Q. Will carpool / HOT lanes still be available to single occupant vehicles between the hours of 7 p.m. and 5 a.m.? Or will a transponder be required during those hours? 

A. Yes, the HOT lanes will be available to single occupant vehicles between the hours of 7 p.m. and 5 a.m. However, if there is congestion between those hours, a toll may be charged until congestion clears. 
Q. Why were the HOT lane sensors installed over the existing HOV lane and the lane next to it?

A. We installed two overhead sensors at each access point to ensure the Good to Go! computer system does not charge a toll to vehicles traveling in the general-purpose lane next to the HOT lane. When the sensors read a Good to Go! transponder, the computer system determines which lane the vehicle is traveling in by comparing signal strengths between the sensors. If the sensor over the general-purpose lane detects a stronger signal, the computer determines the vehicle is in the general-purpose lane and does not charge a toll. If the sensor over the HOT lane detects the stronger signal the vehicle is in the HOT lanes, and the system charges the toll.

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HOV Lanes

Q. Is it legal for a single occupant motorcycle to drive in any HOV or express lane? If not which ones are off limits?

A. One-person motorcycles are indeed allowed to use the HOV lanes. This is actually about safety rather than freeway efficiency. Our reasoning is that HOV lanes generally move along with fewer stops and starts than the general purpose lanes, and that it's safer for two-wheeled vehicles not to be in stop-and-go traffic. More information can be found on WSDOT's HOV Web site
Q. Is it legal for police to drive in the carpool lane without two people in non-emergency situations?

A. Police and other emergency vehicles are allowed to drive in the HOV lanes regardless of whether or not they are responding to an emergency. Often times with the State Patrol, troopers are driving in the HOV lanes to enforce the HOV laws and to look for other traffic violations. 
Q. We've all been told the HOV lanes take cars off the road....Why then is a person driving with a child in the car allowed to drive in the HOV lanes. The child can't drive, so that's not taking a car off the road.
A. HOV lanes have simple objectives: to maximize the number of people that can be carried on the highway and to provide a reliable trip to as many people as possible. Developing a more complicated definition of who is eligible to use HOV lanes would be difficult to explain and enforce and would reduce the number of people who benefit from the reliability that HOV lanes offer. Allowing adults with children to use the lanes enhances enforcement, simplicity, and efficiency.
Q. Why can't a person driving a Hybrid car drive in the HOV lane without a passenger in it?  

A. The main purpose of the HOV system is to move cars on the highways. Fuel efficient cars do not increase the number of people moved on a freeway HOV lane unless there is more than one person in the car. 
Q. On westbound 520, starting at Bellevue Way, signs for the HOV lane show a 3-person minimum. Can you tell me why? 

A.  This requirement on westbound SR 520 between I-405 and the Evergreen Point Floating Bridge helps keep traffic moving safely. The HOV lane on this segment of SR 520 cannot safely carry the kind of traffic that other HOV lanes do. Learn more about the SR 520 rules. 
Q. Can some with a 2-seat car use the 3-person HOV lane legally?
A.  No, it is not legal for a two-seater vehicle to use the 3+ HOV lane on westbound SR 520. Federal law allows motorcycles to use all HOV lanes because it is safer to keep two-wheeled vehicles moving than to have them in start-and-stop traffic conditions. This has nothing to do with how many people the motorcycle is designed to carry.
Q. What is the true purpose of the double white lines?

A. The double white lines are areas where it is illegal to change lanes. WSDOT designates these areas to reduce side swipe collisions and improve safety. The state law is directed at passenger cars, motorcycles, toll payers, and transit and freight vehicles. Emergency vehicles with flashing lights on the way to an incident are the only exception. 
Q. The I-405 HOV lanes are restricted from 5 a.m. to 7 p.m., after that time they are open to all drivers. Does that also apply to the new HOV off-ramps?

A. All HOV direct-access ramps, including those on the Eastside, are only open to buses and vehicles carrying two or more people at all times. Learn more about our HOV program.

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Freeway Signs

When heading southbound on I-405 near Kirkland, can I legally take the 85th Street exit and proceed to the NE 70th Street exit since I technically never "re-enter" the freeway and I am in an exit lane the whole time?

A. It is illegal for drivers to take the 85th Street exit lane on I-405 in Kirkland and proceed to the 70th Street exit because it was designed specifically for drivers entering and leaving the freeway. 
Q: Why are there no "slower traffic keep right" signs on the freeways from Seattle to just south of Bellingham?

A. We currently have nine "keep right, except to pass" signs on I-5 between Seattle and Bellingham. There are five signs in the southbound direction from Bellingham to Everett. In the northbound direction, there are four signs from Mountlake Terrace to just south of Bellingham.

The "keep right, expect to pass" signs are not allowed to be within five miles of each other in the same direction, they can't be placed in an interchange area and they must be more than a half mile away from an interchange. These guidelines were designed to keep costs down, reduce clutter along the sides of the highway and allow drivers to safely merge from the on-ramps to northbound or southbound I-5. We currently do not have plans to add anymore signs.
Q: I spotted some graffiti on a highway sign. Who do I report this to? 

A. You can report graffiti on highways in the Puget Sound area by contacting your local maintenance office.


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Travel Times

Q. When traveling in the southbound direction on I-405 between Kirkland & Bellevue, the overhead traffic sign tells us how many minutes to Seattle on each bridge - but we want to know from where to where?

A. We measure travel times between cities using a central location within each city. For the SR 520 commute, we measure the time it takes to get from just north of the travel time sign on I-405 across SR 520 to the University Street exit on I-5 in downtown Seattle. For the I-90 commute, we measure the time it takes to get from just north of the travel time sign on I-405 across I-90 to the University Street exit on I-5 in downtown Seattle.
Q. Is there a way for people at home to be able to watch the live DOT cameras on their PCs?

The major news stations are the only ones have direct access to our live cameras. We have still shots for drivers that are updated every few minutes. View the full list of cameras

Q: What criteria does WSDOT use when deciding where to place traffic cameras?

Camera locations are determined by the local traffic operations staff throughout the state. They make these decisions based on traffic issues within the region, coordination with the other regions and other agencies, and available funding.

From region to region, traffic issues, which are typically linked to weather or congestion, vary considerably. This can result in different patterns of camera deployment, which is why there may only be two cameras in Yakima, but 10 or more in Everett or Renton. We monitor the cameras at our regional Traffic Management Centers and also post camera images on the Web. We only install cameras on state highways and at other state facilities (such as ferry terminals). Some cities, such as Seattle, and some counties, such as King County, also install their own cameras on their roads. We often work with these other agencies to share video when technically feasible.

If you would like a camera installed on a state road, you can inquire with the local regional traffic engineer about their current plans for camera installations.

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Q. What can drivers do to avoid wet paint?  

A. There are several things drivers can do to avoid wet paint. First, keep an eye out for striping crews and avoiding lane changes on freshly painted lines. Second, watch out for "wet paint" warning signs and warning trucks. Thirdly, check the Northwest region striping Web site to see where crews are striping for the week.

Q. Will WSDOT pay for drivers to remove paint from their vehicles? 

No. If a driver crosses wet paint when wet paint warning signs are present, the state will deny the reimbursement claim. In addition, when a driver crosses the wet stripe their tires remove the paint and thousands of reflective glass beads that help drivers see the road at night and in the rain.

Q. What can I do if I get striping paint on my vehicle?   

A. The paint we use on highways is engineered to last, which means it's nearly impossible to remove if it dries on your car. However, because the paint is water-based, drivers may have about one hour to wash it off with a high pressure hose.

Q. How warm does it have to be for the paint to dry? 

A.  The roadway must be dry and at least 50 degrees.

Q. How long does the striping paint take to dry? 

A.  WSDOT uses fast-drying paint that takes thirty seconds to five minutes to dry.

Q. Where can I find the latest striping schedule? 

A.  The latest striping schedule can be found in the 2009 striping season Web site.


Winter Driving

Q. When is it legal to use studded tires in Washington? 

A. Washington allows studded tires from November 1 through March 31. While sometimes providing additional traction on snow and ice, studded tires damage roadways.

Q. Are there any exceptions/ extensions to the studded tire season? 

A.  There is no individual exception to the studded tire season. The department will review the weather forecast and may extend the March 31 deadline. This information will also be available on the WSDOT's traffic Web site.
Q. I have a four-wheel/all-wheel drive vehicle. Do I have to install chains when signs indicate that chains are required? 

A. As long as your vehicle is equipped with traction tires, chain installation is generally not required on four-wheel/all-wheel drive vehicles. Under extreme weather conditions, the Washington State Patrol (WSP) can mandate that all vehicles chain up, including four-wheel/all-wheel drive vehicles. WSDOT posts signs to keep motorists informed of chain requirements.

Q. How do I find out about when WSDOT plans Avalanche Control?  

The best way to find out information is on our WSDOT Mountain pass reports Web site. You can learn more about the WSDOT Avalanche Control Team on our Avalanche Web site. We are also working on a typical "play by play" explanation on how they do avalanche control on Snoqualmie Pass and Stevens Pass.

Q. Where can I find what should be in a winter safety kit? 

A. Our Winter Driving Web site offers drivers everything about winter driving from what to include in a winter driving safety kit to current mountain conditions. 


Mountain Passes 

Q. Where can I find the latest conditions on the mountain passes? 

A. You can find all the mountain pass conditions by visiting our Mountain pass Web site. By navigating through the map, you find can current weather conditions, restrictions and weather forecasts. Learn more about winter driving
Q. When do crews try to conduct avalanche control on Stevens Pass?

We do avalanche control on Stevens when the avalanche chutes fill and are a safety threat to the highway below. Under ideal circumstances we can schedule our control activities between 3 and 6 a.m. so we have the least traffic impact. Again, when everything works right, traffic only gets held up for 20 minutes or so at a time. The avalanche crew will shoot, the maintenance crew will plow anything that reaches the roadway, and then they'll reopen the roadway to traffic.


Ramp Meters

Q. What are ramp meters? 

A. Ramp meters are stop-and-go traffic signals that control the frequency with which vehicles enter the flow of traffic on the freeway.

Q. Why does WSDOT install ramp meters? 

A. We use ramp meters to reduce accidents and decrease travel times for commuters. Most ramp meters allow only one vehicle through each green light, creating a 4 to 15 second delay between cars entering the highway. This delay helps reduce disruptions to freeway traffic and reduces accidents that occur when vehicles merge onto the highway.

Q. How do I use ramp meters? 
A. If the light is red, stop at the white line. When the light turns green, merge onto the freeway. If there is an HOV lane, buses, carpools and vanpools do not have to stop at the ramp meter signal. They have the right of way over vehicles merging into traffic from the metered lane.

Signal Timing

Q. Why are the red lights not set correctly on Highway 99 from Northgate Area to Everett? 

A.  We do what we can in terms of "working together" to operate the signals smoothly, especially as it pertains to SR 99. The signal along this corridor is owned and operated by, or under contract for, the respective local agencies, with the exception of the signals between Lynnwood and S. Everett at 156th St SW, 148th St SW and at Lincoln Way. Therefore, the Seattle signals are operated by the City of Seattle, the Shoreline signals are operated by King County, the Edmonds and Lynnwood signals are operated by the City of Lynnwood, and the Everett signals are operated by Snohomish County and the City of Everett.


Q. A new roundabout just opened on a road near my house and I don't understand how it works. Where can I find more information?

A. A modern roundabout is a circular intersection where drivers travel counterclockwise around a center island. There are no traffic signals or stop signs in a modern roundabout. Drivers yield at entry to traffic in the roundabout, then enter the intersection and exit at their desired street. You can read more about roundabouts and find links to a five-part video by visiting our roundabout Web page.

Q. Are roundabouts appropriate to use on high-speed highways?

In most locations, roundabouts are appropriate and effective on high-speed highways. Though drivers will have to slow down at a roundabout (much in the same way they would have to at a red light), slowing rather than completely stopping will ultimately allow more traffic to pass through the intersection at a time.

In Washington (and nationwide), more roundabouts are being built and successfully operated on major thoroughfares. The following is a partial list:

On I-90:
First roundabout on a high-speed roadway (SR 203) in the state:  
On SR 206 in Spokane:  
SR 240 in the Tri Cities:
In Arizona, roundabouts have been built at highway interchanges:  
A roundabout at the intersection of two major highways in Wisconsin:  
Maryland has many roundabouts on state highways:  
Several on state highways in Michigan:,1607,7-151-9615_44557_44558-140988--,00.html
And even a few in Alaska:  

For safety stats and more roundabout information, visit our roundabout Web site at

Signal Timing

Q.  Who has to yield to whom when a car turns across a bike lane?

A. Drivers are required to yield to cyclists prior to turning right or left. The Seattle Municipal Code (SMC 11.53.203) states that any vehicle operator approaching a cyclist or pedestrian shall pass to the left at a safe distance and shall not move to the right of the roadway until safely clear of the cyclist or pedestrian.

Q. Why are marine vessel openings on the Hood Canal Bridge allowed during busy commute times?

A. There are no restrictions on marine openings for the SR 104 Hood Canal Bridge. Federal Law (Title 33, Part 177 Draw Bridge Operations) gives marine traffic the right-of-way over vehicular traffic. WSDOT cannot give notice prior to an opening due to Homeland Security regulations, but does alert motorists in the area that an opening is in progress by Variable Message Signs, Highway Advisory Radio and through e-mail or text alerts. These e-mail or text alerts estimate the road-closure duration. The service does not alert subscribers when the bridge reopens to vehicular traffic.

To subscribe to the alerts, go to:, type in your e-mail address, then click on "Hood Canal Bridge Alerts," one of several WSDOT e-mail and text alert services

Q. What are the three parallel lines on each side of the right lane on many highways across the state?

A. These strips in the wheel paths of the right lane on some concrete highways contain steel bars called "dowel bars" that help hold the concrete panels together. The dowel bars were installed after the pavement was showing signs of rough edges and gaps between the concrete panels, caused by heavy use of the right lane, resulting in a rough ride and accelerated deterioration. The process of installing these steel bars is called dowel bar retrofitting. The process restores the structural integrity of the roadway and extends the life of the pavement.

You can see photos of this process on our Flickr site:  

Q. How do traffic signals detect motorcycles and bicycles?

A. Motorcycles and bicycles may have problems at some traffic signals when they encounter red lights because most traffic signals use induction loop vehicle detectors. The induction loop detectors sense the change in the magnetic field caused by vehicles that enter the signal detection zone. Motorcycles and bicycles do not have much ferrous metal and may have trouble activating a signal change at a traffic light. WSDOT keeps a record of and reviews locations at which motorists experience delays. Adjusting the existing detection equipment can sometimes improve detection. Typically, the best place to place your motorcycle (or bicycle) would be in the center of the lane within about one foot of the stop bar.


Still not find what you're looking for? Then e-mail our Public Affairs office to submit your question.