That means motorists can expect to see a number of projects aimed at improving safety throughout the city. All four projects are fully funded by the City Safety grants with no local match required. The four projects were approved by the City Council during its Monday meeting.
Here is a look at the four projects:
1) 176th Street SW between 52nd Avenue W. and 44th Avenue W. The proposal is to modify existing lane striping. The project will convert (re-stripe) this roadway from four lanes to three lanes (two through lanes and one center turn lane) with bicycle lanes between 52nd Avenue W and 44th Avenue W. This is commonly referred to as a “road diet.”
Various studies have determined that road diets reduce total crashes by 6 percent or less. Road diets can offer benefits to both vehicles and pedestrians. On a four lane street, drivers change lanes to pass slower vehicles (such as vehicles stopped in the left lane waiting to make a left turn). In contrast, drivers’ speeds on two-lane streets are limited by the speed of the lead vehicle.
Thus, road diets may reduce vehicle speeds and vehicle interactions during lane changes, which potentially could reduce the number and severity of vehicle-to-vehicle crashes. Pedestrians may benefit because they have fewer lanes of traffic to cross, and because motor vehicles are likely to be moving more slowly.
The City Council approved Public Works’ request to prepare design plan, specifications and estimates.
2) Safety improvements throughout the city. The project will complete the following safety improvements:
a) Implement flashing yellow arrow traffic signal heads. Flashing yellow arrow (FYA) traffic signal heads for left-turn movements during permissive turn intervals will be implemented at select signalized locations (estimated 30 intersections). The FYA have been found to have a higher level of understanding and correct response by left-turn drivers. FYA have been found to reduce both collision rates and collision severity. Other benefits of FYA include greater flexibility in signal coordination and the ability to vary phasing by time of day.
b) Install pedestrian countdown traffic signal heads. Pedestrian countdown traffic signal heads let the crossing pedestrian know how much remaining time they have to cross the intersection. They have been found to improve pedestrian safety and are also a federal requirement for all new pedestrian signal heads.
c) Install permanently mounted speed radar signs. The project will implement speed radar signs at approximately 3 to 5 locations around the city. The speed radar signs will be solar powered and will display the speed of the passing vehicles.
3) Highway 99 and 196th Street SW. The proposal is to improve the existing lane striping and signing. The project will complete the following safety improvements:
a) Installation of advanced street name signs. The project will install advanced street name signs with “next signal” lettering (white on green) on the two primary approaches at each signalized intersection along the Highway 99 (212th Street SW to 164th Street SW) and 196th Street SW (76th Avenue W to 24th Avenue W) corridors. Advanced street name signs provide road users with improved guidance, reducing the attention required to find street names and giving drivers more time to plan their actions prior to intersections. These benefits are especially valuable at wide, high-volume intersections. Additionally, driver frustration is reduced as they can more easily find their destination without getting lost.
b) Installation of internally illuminated overhead street name signs. This project will install LED internally illuminated overhead street name signs on the traffic signal mast arms of the two primary approaches at each signalized intersection along the Highway 99 (212th Street SW to 164th Street SW) and 196th Street SW (76th Avenue W to 24th Avenue W) corridors. The benefits are similar to those listed for advanced street names signs above.
c) Replacement of thermoplastic intersection pavement markings with Methyl Methacrylate (MMA) pavement markings. Pavement markings provide important guidance and information to the road user. Pavement marking durability is very important along high traffic volume roadways. Over time, pavement markings become worn, making them much less visible to the road user, thereby affecting the safety of the roadway. Crosswalk and stop line pavement markings are particularly susceptible to wheel wear. The project will replace thermoplastic crosswalks, stop lines, and arrows with Methyl Methacrylate (MMA) at each signalized intersection along the Highway 99 (212th Street SW to 164th Street SW) and 196th Street SW (76th Avenue W to 24th Avenue W) corridors.
d) Installation of “Bus Rapid Transit” type lane line markings (SR-99 only). The project will replace Raised Pavement Marker (RPM) lane lines along the NB and SB curb lanes of the Highway 99 (212th Street SW to 164th Street SW) corridor with wide profiled MMA lane lines to improve visibility and emphasize the existing Bus Rapid Transit (BRT) lanes. BRT pavement markings consist of wide dotted lane lines through mid-block areas and wide solid lane lines approaching intersections.
4) Highway 99 and 196th Street SW.
This project will implement adaptive signal control along Highway 99 and 196th Street SW through the entire city limits.
Highway 99 and 196th Street SW are the most congested and highest collision corridors in the city. The project will reduce congestion (and in effect collisions) by implementing real-time adaptive traffic signal control along Highway 99 (238th Street SW to 164th Street SW) and 196th Street SW (76th Avenue W to 24th Avenue W). Additionally, Lynnwood is partnering with the City of Edmonds to include the four Edmonds Traffic Signals located within the project limits along Highway 99. Lynnwood will be the lead agency.
Adaptive traffic signal control is the process by which the timing of a traffic signal is continuously adjusted based on the changing arrival patterns of vehicles at an intersection. Benefits include:
– Reduced collisions due to reduced congestion (less stopping cars means fewer conflicts)
– Reduced congestion due to smoother traffic flow
– Green light time can be equitably distributed for all traffic movements
– Traffic signals adapt to changing traffic conditions in real time
– Improved travel time reliability by progressively moving vehicles through green lights (some have experienced a travel time reduction of more than 20 percent and a delay reduction of more than 40 percent)