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System seeks to improve traffic flow on Division

MONDAY, JULY 29, 2013

Adaptive signal offers real-time control

Spokane city traffic engineers hope to improve the flow of vehicles on North Division Street with a new computerized signal system that adapts to hourly changes in traffic volume.

The city plans to spend up to $1 million for the “adaptive signal control.” Once the new system is in place by winter, it will become the first traffic control system of its kind in Washington.

“The goal of the system is to adjust to traffic and flows in near-real time,” said Valla Melvin, senior traffic engineer on the project.

The Federal Highway Administration is providing $850,000 for congestion management and air quality. The city is paying the balance as its required match for the grant.

Adaptive signal control is used in Europe and Australia and is gaining in interest in the U.S., Melvin said.

The system will adjust signal timing to keep traffic moving more smoothly as volumes and directions of travel change throughout the day. The adjustments should prevent long waits at busy intersections such as at Francis and Wellesley avenues.

Studies have shown the system could bring up to a 40 percent decrease in delays, a 25 percent improvement in travel time and a 22 percent reduction of volatile organic compound pollution. Fuel savings could be 10 percent.

Melvin said traffic along Division has been difficult to manage because it ebbs and flows unpredictably.

The old pattern of morning and evening rush hours has given way to heavier traffic at midday. Drivers use the corridor for a wide range of needs, including dining and shopping.

Traffic typically peaks from 11:30 a.m. to 5 p.m. weekdays and from 11 a.m. to 3 p.m. Saturdays.

The FHA has studied various types of adaptive systems and issued guidance to states and local governments on what to consider.

Melvin and a consultant developed a 40-page request for proposals specifying features for the system. Aegis ITS, of Anaheim, Calif., was chosen as the vendor.

The Aegis product has elaborate data collection to help engineers manage traffic. “The system is big on performance measures,” Melvin said.

It also has an interactive feature that allows buses to gain a few seconds of green light time so they can stay on schedule. Buses in Spokane are expected to be equipped to use the feature in the future.

City street crews are installing the system, including upgraded signal cabinets and controllers.

Lane striping

Lane striping this week in two locations in the Spokane area will cause lane restrictions.

Crews will place stripes on the Hamilton Street on-ramps and off-ramps for Interstate 90 and on the Spokane River bridge leading to Trent Avenue and Hamilton Street.

The off-hours work is scheduled for today through Friday from 7 p.m. to 6 a.m.

In the other job, workers will be restriping the intersection of Newport Highway and Mount Spokane Park Drive on Tuesday through Friday from 7 p.m. to 6 a.m.

County projects

Spokane County commissioners last week approved spending $249,000 to replace a bridge over Sanders Creek on Cheney-Plaza Road. The job will involve county road workers supplemented with day labor, commissioners said.

Commissioners also approved an extension of a sanitary sewer trunk along U.S. Highway 2 from Perry Road to Pittsburg Street for $645,000. The contractor is Big Sky Development Inc., of North Idaho.

Valley closures

In Spokane Valley, Fourth Avenue from Progress to Sullivan roads will be closed from 7 a.m. today through 5 p.m. Wednesday for utility work.

Bettman Road between 11th and 14th avenues will have lane restrictions and brief driveway closures during daytime hours Mondays through Fridays through August. Drainage improvements are being installed.

Montgomery Drive just east of Pines Road will have lane reductions and minor delays on Thursday from 7 a.m. to 6 p.m. for utility work.

Portions of University Road between Fourth and 16th avenues will be reduced to one lane in each direction on Tuesday and Wednesday from 6 a.m. to 5 p.m. for utility work.

Downtown sidewalk upgrades

Spokane city officials last week announced a $1.3 million project to replace and improve downtown sidewalks through a federal grant and city matching funds.

The work is planned for Howard Street, the area around the Spokane Transit Authority Plaza, and the arts and entertainment district.

Bike racks, planters, new street trees, new street tree grates and garbage cans are included. Handicapped-accessible features are also part of the job.

The Downtown Spokane Partnership is providing $49,600.

Argonne repaving

Repaving work on Argonne Road is set to start today from Wellesley to Bigelow Gulch. Traffic will be routed onto a single lane in each direction.

The contractor is adding 962 feet of sidewalk on the east side of Argonne, along with signs and striping for bicycles.

The project costs $2.5 million, with $2.1 million coming from a grant.


The repaving and sidewalk work on Pines Road from 32nd to Trent avenues will move onto the Pines overpass on Interstate 90 starting today and continuing on Tuesday. Work is being done during off-hours from 7 p.m. to 7 a.m.

Work is continuing on other state highway projects, including a new Francis Avenue overpass bridge east of Market Street and repaving of Francis west of Division and continuing north on Nine Mile Road.

Division work Tuesday

Division Street in the vicinity of the former Burgan’s Furniture store in the north 1100 block will have two lanes closed Tuesday from 7 a.m. to 3 p.m. for utility work as part of a redevelopment of the property.

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