Week of Jan. 21, 2008

Roads east of Redmond to get smarter

Avondale Road

Work will begin by the end of the month on the Avondale/Novelty Hill Road project – a joint effort between King County, the city of Redmond, and the Washington State Department of Transportation (WSDOT). It includes the installation of fiber optic links and real-time traffic cameras that will allow the three jurisdictions to share traffic data, synchronize traffic signals, and remotely operate those signals when necessary.

Signal synchronization and other ITS elements can achieve significant reductions in travel time and fuel consumption, which also improves air quality, traffic safety, and eases stress for motorists. The Roads Division’s before-and-after studies on existing ITS corridors shows reduced travel times between 20 percent and 45 percent in the peak direction of travel. It’s also a cost-effective way to improve travel times for all motorists – including transit.

The corridor east of Redmond is a prime candidate for an ITS upgrade.

“Novelty Hill Road and Avondale Road are key commuter routes for residents of Northeast King County and Southeast Snohomish County,” said Linda Dougherty, director of the King County Road Services Division. “This project will link a 3.2-mile stretch that runs from unincorporated areas, through the city of Redmond, and connects with State Route 520. This is just Phase 1, but it will lay the foundation for future improvements.”

ITS projects throughout King County use high-speed data and video transmission to connect traffic control centers to the individual intersections in the corridor. The high-speed transmission takes place along fiber optic cable, which provides high bandwidth at a low relative cost.

Phase 1 of the project focuses on the Avondale/Novelty Hill Road corridor between SR 520 and 208th Avenue Northeast. The city of Redmond currently owns fiber optic cable along Avondale Road between Union Hill Road and Avondale Road. There is a need for additional fiber between Union Hill Road and State Route 202
where WSDOT has a fiber hub currently providing a communication link to its system. This project will expand the use of the WSDOT hub to provide a link between King County, Redmond, and the signals and cameras along the corridor. Total project cost is $975,000.

“We will also be upgrading eight signals and adding two new cameras in the corridor as part of Phase 1,” said King County Project Manager Aileen McManus. “Adding that equipment and linking our traffic control centers will provide us with much more real-time data, which allows us to provide more congestion relief for the vehicles traveling through the corridor.”

McManus said smooth operation of any ITS corridor is based on pre-written signal timing plans that are individualized for the traffic flow in that specific corridor. A single plan per corridor is not enough since traffic congestion can vary significantly between weekday and weekend, time of day, weather changes, and random events such as collisions and accidents.

She said the plans are in depth, individualized computer programs that evaluate traffic volumes, types of vehicles, distances between intersections, grade, number of lanes, turn signals, and all the factors that affect the flow in both the overall corridor and each segment of the corridor. Each plan must be tested in the field before it is finalized and added to the mix for that particular corridor.

Even though the county’s largest ITS corridor – the “Trans Valley” connecting Benson Hill area to Tukwila between 151st Avenue Southeast and Southcenter Parkway – has been in operation for several years, traffic engineers added a new timing plan to its repertoire in November. Working with WSDOT and the two cities, the engineers created a holiday signal timing plan to improve traffic movement for both shoppers and commuters in the corridor that was in effect from Thanksgiving to New Year’s.

The county also has a completed ITS project between Kirkland and North Redmond along Northeast 124th Street from 100th Ave NE to State Route 202. Traffic signal plans have been added on that corridor over the past two years to adjust for the WSDOT I-405 construction projects in the Totem Lake area.

“ITS connections let us develop more plans for a variety of scenarios, and they allow us to switch between plans more quickly when there is an accident or sudden change in traffic conditions along the corridor,” said McManus.

The work on the Avondale/Novelty Hill Road project will require little construction, but there could be occasional lane closures for the next two to three months while crews work along the roadway shoulder to install the fiber optic cable. Design work is also underway on three more ITS projects: Juanita-Woodinville Way near Northeast 160th Street; 100th Avenue Northeast in Juanita; and South 277th Street near Kent.

Round up on December storm repairs Holmes Point Drive slide. The storms from the first week of December may be a faint memory for most, but they are still keeping the King County Road Services Division busy. Emergency fixes were made shortly after the Dec. 2-3 storms, but more permanent repairs are underway at three locations: Holmes Point Drive Northeast – Work began last week to stabilize the slope supporting the roadway in the 13600 block of Holmes Point Drive Northeast. The road is closed through February until the project is complete. South 272nd Way – There was a slide on the east side of this road when a culvert was damaged during the heavy rainfall. The repairs start this week and should be done by mid-February. The road will not be closed during construction, but motorists should expect intermittent lane closures. Southeast Newport Way – A sinkhole was repaired in early December. Now, a temporary liner will be inserted in the culvert under the roadway to prevent further deterioration of the culvert. Weather permitting, construction is scheduled to begin in early February and be completed by the end of the month. The Road Division is exploring options and costs for permanent repairs.

Mercer Island Park-and-Ride has reopened The Mercer Island Park-and-Ride at 80th Avenue Southeast and North Mercer Way reopened Jan. 21, after the completion of a two-year project to increase parking, add bicycle storage, and improve other passenger amenities. Sound Transit was in charge of the $16.8 million construction project. The renovated park-and-ride will be will be operated in partnership with King County Metro Transit and serve both Sound Transit and Metro bus routes, including: Metro routes 201, 202, 203, 204, 205, 213, 216, and 942; and ST Express 550 and 554.

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