MARYSVILLE As city traffic grows, so do the headaches for traffic engineers as they try to keep up.
Last summer city workers installed a brand new traffic signal at the
three-way intersection of 67th Avenue and 84th Street, next to Grace Academy and Cedarcrest Golf Course. As soon as engineers switched it on two cars rammed right into each other, much to their chagrin.
And so it goes, as five more signals are slated for installation in the city limits this year and other road re-alignments and improvements go ahead.
Snohomish County will be spending $2 million to upgrade an intersection south of Shoultes Elementary School, at 51st Street and 122nd, and Marysville will pitch in $400,000 of its own funds to relocate city-owned utilities lines buried nearby. In addition to raising the road bed, the county will install a traffic signal.
That project is much more involved than most others in the city, according to Jeff Massie, assistant city engineer with the Marysville Public Works Department. Adding a signal to an intersection costs about $150,000 to $250,000 to start, and thats just to put up the stanchions and signals. If the city has to acquire right-of-way, the costs will balloon quickly. A typical improvement sets the city back by $500,000 to $1.5 million, according to Massie, but developers are often required to foot the bill for intersections near their projects. They must mitigate the effects of new traffic drawn to their projects by building new lanes, installing signals or building completely new intersections with all the bells and whistles, Massie said.
A new Wal-Mart store planned for the intersection of SR 9 and SR 528 will have to provide those, for example, including a new signal at SR 528 and 83rd Street, and possibly at 87th Street as well, Massie said.
Other new signals are expected at various locations, but city engineers are touting a new scheme at the current bottleneck west of Allen Creek at Fourth Street/SR 528. SR 528 will be re-striped to provide two lanes in each direction and a center turn lane, and the bridge over the creek will be re-striped as well. The Washington State Department of Transportation gave the city a variance to allow two lanes of traffic in each direction on the bridge, which is too narrow for WSDOT standards, Massie said. There will be no shoulders or turn lane on the bridge, which will retain its raised sidewalks.
Just west of the bridge is a double-trouble combination of two intersections where 47th Street crosses Third and Fourth streets. Third Street morphs into the busy Sunnyside Boulevard which carries an increasing load of traffic from new residential neighborhoods south of town, and a new strip mall at 47th and SR 528 was just built. That allowed the city to acquire another turn lane to be built, and engineers will improve both intersections at the same time.
The City Council on May 14 approved the purchase of an easement on the Exxon gas station property and will widen the street and provide more turning and collector lanes. Currently the Third Street intersection is a four-way stop and has too much traffic for cars to take turns waiting for each other to proceed.
We need to do the signal improvement at Third and Fourth streets to platoon traffic through more efficiently, Massie said, adding that both will be timed and coordinated with each other. Basically back-ups to each one affects the other one.
The wider roads will increase the road safety, but that is about all for now, Massie cautioned.
Theres no plans to increase the speed on that, at least this point in time, he said.
The $2 million intersection planned in county jurisdiction is at a T where 51st Avenue crosses the fork in Quil Ceda Creek. In addition to working around a sensitive waterway and riparian zone, the county plans to raise the roadbed to improve sightlines and level out a dip in the road. Another tool the city is thinking about using is the round-about, like the one at the intersection of 51st Avenue and 108th Street NE. They have worked better than signalized intersections in many cases and are much cheaper to install and maintain, according to Massie.