WSDOT's approach to reducing congestion
Urban congestion matters to all of us - moms with kids driving to soccer practice, commercial truck drivers moving our freight and goods, commuters rushing to get home to thier families, and workers in roadway construction zones. We all want to get where we need and want to go, and have the time to do the things we need and want to do.
Our transportation system is all connected - it isn't just about roads and it isn't just about transit - its about giving people better options that work for them. To be successful, we all have to work together - railroads, transit agencies, local governments, ports, and the Washington State Department of Transportation - to fight congestion and give people practical, reliable transportation options.
Find out what WSDOT is doing to tackle congestion:
Measuring Congestion
Over the last several years, the Washington State Department of Transportation has focused on developing congestion measurements and benchmarks to present a clear, more accurate picture of what's happening on some of our state's most congested freeways. Our approach to congestion is targeted to measuring efficiency, reliability and progress that people can see and experience. We are concentrating on reporting the effectiveness of congestion relief programs that support reliable travel times and greater system efficiency for commuters.
An annual report on congestion measurements is presented in the Gray Notebook, WSDOT's quarterly performance report. Our latest annual update for measuring congestion can be found in the index for Congestion.
Our principles for measuring the extent of congestion and our progress toward finding solutions include:
- Use real time measurements (rather than computer models) whenever possible
- Measure congestion due to incidents as distinct from congestion due to inadequate capacity
- Show whether reducing congestion caused by incidents will improve travel time reliability
- Demonstrate both long-term trends and short-to-intermediate term results
- Communicate possible congestion fixes using an "apples-to-apples" comparison with the current situation (for example, if the trip takes 20 minutes today, how many minutes shorter will it be if we add a freeway lane or improve the interchanges?)
Managing Congestion
Some want more freeways, some want more transit, some want both, some want to focus on freight movement, and some want nothing at all. Our goal is to make strategic improvements to achieve greater efficiency of the state's transportation system. This is accomplished through a balanced investment plan of programs and services that include:
Technology advances in motorist information
Our approach to reducing congestion is multi-faceted, focusing on reducing the causes of congestion, providing capacity improvements, and making the most efficient use of the existing transportation system. This includes giving motorists access to current information on roadway conditions, allowing them to make informed decisions about their travel route and plans:
- Real-time commute information
Estimated travel-times are updated every 5 minutes for 32 commute routes within the Central Puget Sound. This program uses traffic flow data to help predict travel times based on current traffic conditions
- 511 Travel Information
Know before you go. Current traffic and weather information is available by simply dialing 5-1-1 from most phones.
- Travel Alerts
Find out about lane closures or delays caused by construction, collisions or weather.
- Statewide Traffic Cameras
Check on weather and traffic conditions around the state from your home or office. New traffic cameras are being added all the time.
- VAST
Vancouver Area Smart Trek (VAST) provides travel information for the Vancouver, WA and Portland, OR urban area.
- Traffic Systems Management Center (TSMC)
Of WSDOT's six TSMC facilities, the Northwest Region TSMC, located in Shoreline north of Seattle, is the oldest and largest. In the Puget Sound area, the TSMC is the control center for several electronic devices used for traffic management such as variable message signs, ramp meters, and highway advisory radio to get information to motorists quickly.
Other TSMCs in Tacoma, Vancouver, Yakima, Spokane operate 24 hours a day, seven days a week. The TSMC in Wenatchee operates 24/7 during the winter months. Many TSMCs are co-located with the Washington State Patrol, which allows us to share information and respond quickly to highway incidents and roadway driving conditions. Our TSMC operators monitor traffic cameras and can program the highway advisory radio, electronic message signs, update web information, and dispatch Incident Response and maintenance crews from the center.
Incident Response
Almost half of our congestion on urban freeways is caused by crashes and broken down vehcles. For every minute a lane remains blocked, four to 10 minutes of congestion may result. To address this, we have expanded our Incident Response program in order to clear collisions more quickly and in doing so, reduce traffic backups and delays. Our Incident Response clearance goal is to clear all incidents within 90 minutes.
High Occupancy Vehicle Lanes - (HOV)
HOV lanes are designed to move more people in fewer vehicles than the full lanes next to them. By reserving these HOV lanes for people who share rides, we provide more reliable trips for buses, carpools and vanpools. HOV lanes also add capacity for general-purpose lanes when carpools move from the regular lane into the HOV lane.
- In the 1970s, the Department set out to build a connected system of HOV lanes on Puget Sound freeways, including I-5, I-90, I-405, State Route (SR) 167, SR 520, and SR 16 in the Puget Sound region. To date, we've invested over $1.5 billion in HOV lanes and ramps, building approximately 200 miles of a 300-mile core HOV system.
- Completion of the HOV lanes on I-5 is getting closer with pieces remaining to be completed through Everett. In July 2007, we completed the I-5 HOV lane from 320th in Federal Way to the Pierce County line. In 2002 we completed HOV lanes for teh entire 30-mile length of I-405. The HOV lane system on State Route 520 also needs to completed and/or upgraded.
- In Pierce County, we've completed the first of several projects to add HOV lanes on I-5 through the Tacoma area, from the SR 512 Interchange to South King County, including major reconstruction of the I-5 and SR 16 Interchange. Work on SR 16 from I-5 to the Purdy Interchange is under way.
- Sound Transit is the lead agency for construction of HOV direct-access connections at a number of key locations throughout the region. These projects are funded and programmed by Sound Transit and are scheduled to be completed by 2006.
- A HOT lane pilot project is being planned for the HOV lanes on SR 167. WSDOT is using the pilot project to assess whether or not HOT lanes are a viable solution to relieve congestion, and could be implemented on other highways in the Puget Sound region. HOT lanes maintain free, priority status to transit and carpools, but also allow solo-drivers that pay a toll to use the lanes. Toll rates will be variable and will depend on the level of congestion.
Ramp Metering
By using ramp meters to stagger traffic that is merging onto the freeway, bottlenecks at on-ramps are reduced. Without ramp meters, many cars try to merge at once. Drivers on the freeway slow down to let the cars enter, and these slower speeds quickly cause backups. If, however, cars enter the freeway in a spaced, controlled manner, they merge easily with less disruption to mainline traffic. A short wait on the ramp allows drivers to increase their average freeway speed and shorten freeway travel times. Ramp meters are used in 112 locations in the Central Puget Sound area. Ramp meters have also been introduced in Pierce County along SR 16.
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Washington State Ferries
Not only is Washington State Ferries (WSF) the largest ferry system in the nation, it is also Washington's second largest transit system, second only to King County Metro. In 2005, WSF transported more than 6 million walk-on passengers. In addition, WSF promotes bicycles as an alternative means of transportation through its Bicycle Pass Program, which offers a reduced fare for regular bicycle commuters.
WSF's Rideshare Program for vanpools and carpools provides priority boarding for registered users. In 2005, more than 300 vanpools (199) and carpools (114) were active participants in program in the Central Puget Sound area.
Transportation Demand Management (TDM)
Also known as trip reduction, TDM is an umbrella term for strategies that reduce or shift use of the roadway. TDM strategies include the Commute Trip Reduction (CTR) Program; park and ride lots; vanpools; and planning for land use that requires less driving.
- The CTR Program uses partnerships between employers and government to encourage change in commuting habits. The CTR Program encourages employees to ride the bus, vanpool, carpool, walk, bike, work from home, or compress their workweek. In 2005, CTR commuters took 20,400 vehicle trips off the state's roadways every morning. This saves space on the roads and reduces air pollution by about 3,800 tons and gasoline consumption by about six million gallons each year.
- Park and ride lots enhance the convenience of transit, vanpools, and carpools. WSDOT owns 62 lots in Puget Sound, with 12,000 parking spaces. King County lots have an average occupancy of 91 percent. WSDOT plans to increase the capacity of its park and ride lots.
- The Puget Sound region leads the nation in vanpooling. There are currently 1,353 vanpools in Puget Sound; they remove approximately 9,400 vehicles from area roads each morning. A recent WSDOT study has estimated the potential for nearly 11,000 new vans in the four counties-equivalent to 7 percent of total commuters in the region.
Projects to Reduce Congestion, Bottlenecks and Chokepoints
Several projects are funded and scheduled or already under construction to reduce congestion in these areas:
Central Puget Sound:
- I-5 Everett Expansion and HOV Lanes
Construction is underway on this project to fix one of our state's most notorious bottlenecks. Crews are widening I-5 through Everett to add an extra merging lane between 41st and US 2 and extend the HOV lanes from Boeing Freeway (SR 526) to US 2 (Hewitt Avenue Trestle). Crews will also build a new interchange at 41st Street, a new right-hand Broadway Avenue exit and will modify the existing left-hand exit for carpools, vanpools and buses to help eliminate sudden lane changes. Traffic will move more smoothly and safely when we complete this project, which eliminates chokepoints, reduces merging, and adds lanes.
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I-5 Shoreline Northbound Auxiliary Lanes (NE 175th St. to NE 205th St.)This section of northbound Interstate 5 in Shoreline is congested due to large traffic volumes and merging traffic. WSDOT is building an auxiliary lane (also called an add/drop lane) on northbound I-5 from the NE 175th Street on-ramp to the exit-only lane for NE 205th Street. The new lane will help relieve congestion and improve safety by providing more room for motorists to speed up and merge when getting on and off the freeway.
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I-5 – South King County HOV Lanes
Ask any driver who travels on I-5 in south King County -- this section of freeway is one of the busiest in the state. Crews are extending HOV lanes from S. 320th in Federal Way to the Pierce County Line to increase freeway capacity. Traffic often overloads I-5 in South King County, especially during the morning and afternoon commutes. This is part of WSDOT's comprehensive plan to add carpool lanes on Interstate 5 south through the Tacoma urban area. The project also adds traffic cameras, installs hardware needed to create traffic congestion maps, and improves the existing pavement.
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SR 18, Corridor from Auburn to I-90
This is a several phase project to widen SR 18 to four lanes from Auburn to I-90, including many interchange projects and other details. Our aim: increase capacity, reduce congestion and enhance safety. While major portions of the project are complete and others are currently under construction, other parts of the project are in earlier phases of development or lack funding. WSDOT estimated traffic delays during 7 hours per day by 2010 and 9 hours per day by 2020 if this project is not completed. Drivers can expect traffic delays one hour per day in 2010 and 2020 if the project is completed.
Pierce County:
- State Route (SR) 16 from SR 302 to Nalley Valley Viaduct: Six projects of the 22-project Tacoma/Pierce County Core HOV Program (http://edit.wsdot.wa.gov/NR/exeres/www.tacomatraffic.com) are located on SR 16. These six projects add High Occupancy Vehicle (HOV) lanes, improve intersections and build a new bridge over the Tacoma Narrows. Our aim: improve safety and mobility and reduce congestion on the SR 16 corridor. While portions of SR 16 are complete and others are scheduled for completion in 2007, other parts of the project are in earlier phases of development or lack funding. If no improvements had been constructed along the SR 16 corridor, WSDOT estimated that by 2020, during the peak commute periods it would take over 1 1/2 hours (98 minutes) to drive between Purdy and I-5. With the improvements being built, the 2020 drive time between Purdy and I-5 is estimated to be 26 minutes during the peak commute period.
Vancouver/Portland:
- I-5 – Salmon Creek to I-205
This project widens I-5 in Vancouver to three lanes, plus an auxiliary lane, in each direction from NE 99th Street (Salmon Creek) to the junction of I-205. Traffic flow in the I-5 corridor between the Main Street interchange in Vancouver and the I-205 junction will be improved. Through computer modeling, it is estimated that if this project is not built, afternoon travel speeds in 2010 and 2020 would be 42 and 26 mph respectively. Once completed, average travel speeds in 2010 and 2020 are projected to increase to 60 and 51 mph respectively. Construction began on August 20, 2003 and completion is expected by fall 2007.
- I-205, Mill Plain Exit – 112th Connector
This project will provide a direct connection to NE 112th Avenue from the off ramp of northbound I-205 to westbound Mill Plain Boulevard. It is a partnership project with the city of Vancouver. When completed, the new ramp will reduce delays around the intersection of Mill Plain Boulevard and Chkalov Drive and at the northbound I-205 off ramp to Mill Plain Boulevard by 50 percent during peak travel times in 2020. The project is scheduled to start in spring 2006 and be completed in December 2007.
Spokane:
- US 395, North Spokane Corridor
This project addresses the need for a major improvement to allow motorists and freight to move through metropolitan Spokane along the corridor from I-90 to US 395 at Wandermere. When completed, the North Spokane Corridor (NSC) will be a 60-mile per hour, limited access highway with a direct connection to I-90 just west of the existing Thor/Freya Interchange. Other interchanges will be placed at locations such as Trent Avenue (SR 290), Wellesley Avenue, Francis / Freya Street, Parksmith Drive, US 2, and US 395 at Wandermere. Computer models estimate that in the year 2025 the travel time on the NSC, for a northbound PM peak trip between Sprague Avenue and Magnesium Road, will be 7 minutes. If the NSC is not built, the same trip on Market Street (an urban arterial adjacent to the NSC alignment) will take 23 minutes.
- SR 270, Pullman to Idaho
In fall 2007, WSDOT completed a project that improves capacity and safety by widening SR 270 from a two-lane to a four-lane facility, with a center turn lane. Through computer modeling, WSDOT estimated that if this project was not built, traffic congestion would average 3 hours a day by 2010 and 4 hours a day by 2020. Without the project average afternoon travel speeds in 2010 and 2020 would be 44.5 and 39.5 mph, respectively. Speeds are projected to be 55 mph for each forecast year with the project completed.
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