Traffic meters planned for SR 16

In another sign that transportation improvements are coming to Pierce County, next week the Washington State Department of Transportation will activate its first ramp meters on State Route 16. Starting at 6 a.m. on Tuesday, August 30, WSDOT will begin metering the five eastbound SR 16 on-ramps between State Route 302 (Purdy) and the Tacoma Narrows Bridge in an effort to reduce chronic eastbound traffic congestion worsened somewhat by roadway construction associated with the bridge project.

Although SR 16 traffic volumes are still in their “summer” (lower volume) phase, activating ramp meters now will allow WSDOT to fine-tune the timing of the meters, and allow drivers to become accustomed to driving with the meters, before the expected higher traffic volumes come with the beginning of the school year.

Ramp meters are stop-and-go traffic signals placed on highway entrance ramps. They create a short delay between cars entering the highway system, resulting in faster overall travel times due to decreases in collisions at merge points, and a more even traffic flow that maximizes highway capacity.

WSDOT has used ramp meters for years in King and Snohomish counties to manage congestion. Because of their effectiveness, WSDOT is extending their use into Pierce County.

The five eastbound ramps to be metered include SR 302 (Purdy), Burnham Drive, Wollochet Drive, Olympic Drive NW, and 36th Street NW. At the four latter ramps, meters will allow one car to proceed with each green light.

At the SR 302 on-ramp, the meter will allow two cars to proceed on each green light to accommodate the high volumes of traffic using that ramp. The ramps will be metered during morning peak commute hours and at other times as traffic conditions warrant. In general, motorists can expect to see the meters operating on weekdays between 6 a.m. and 10:00 a.m., with ramp meter timing adjusted to reflect real-time traffic conditions.

WSDOT staff will closely monitor the effects of the meters on highway and ramp traffic both on site and remotely, especially during the initial turn-on phase. Meter rates will be adjusted from WSDOT’s Traffic Management Center in Tacoma, with the goal of providing the best balance of ramp traffic to highway traffic to keep people moving. Motorists can help the process by remembering to pull up to the stop bar at each ramp meter. Loops embedded in the pavement at the stop bar signal the meter to be activated.

Studies completed by WSDOT traffic engineers indicate that the ramp meters will not eliminate morning traffic congestion on SR 16, but they will reduce the amount of time necessary to get from the ramps to the bridge. For example, during the peak weekday traffic hour, 7:30 – 8:30 a.m., drivers using the SR 302 on-ramp can expect to reach the bridge about two minutes faster when the meters are operating.

Even drivers using the 36th Street NW on-ramp, the ramp closest to the bridge, can expect to get to the bridge about two minutes faster during that peak hour (between 7:30 – 8:30 a.m.) when the meters are operating. While two minutes may not seem like a big time savings, when multiplied by the typical 15,000 vehicles that cross the bridge eastbound during the daily morning commute period, this savings adds up.

Construction of new highway capacity along SR 16 is underway. In the interim, using proven tools to manage traffic demand that will reduce the severity of backups and delays will provide an incremental improvement.

Motorists are also reminded that earlier this summer, WSDOT activated traffic cameras along the same SR 16 corridor to extend live camera coverage. These images are downloaded to WSDOT’s website and available for viewing at http://www.wsdot.wa.gov/traffic/gigharbor.

For more information on the benefits of ramp meters, visit http://www.wsdot.wa.gov/projects/sr16narrowsbridge/misc/meters.