Starting Monday, June 15, crews will begin daytime flagging operations on SR 702 at Harts Lake Road for roundabout construction. See detailed information below.
Project overview
Safety improvements are coming to two intersections on State Route 507 and State Route 702 in south Pierce County. Construction crews will build a single-lane roundabout on SR 507 at 208th Street near Spanaway and SR 702 at Harts Lake Road South near McKenna. Roundabouts help slow traffic and reduce the potential for collisions.
What to expect
SR 702 at Harts Lake Road South
From 7 a.m. to 5 p.m. Monday, June 15, through Thursday, June 18, and Tuesday, June 23 through Friday, June 26, travelers can expect daytime flagging operations at this location. Crews will place project signs and install silt fencing along the project area to prepare for roundabout construction.
Reduced lanes and speed limit
Starting Monday, June 29, the speed limit on SR 702 will be temporarily reduced from 45 mph to 25 mph from milepost 0.53 to 0.63. Travelers will see temporary traffic lights and single-lane alternating traffic around the clock.
SR 507 at 208th Street South
Temporary traffic signals are in place around the clock to alternate directions of traffic through the roundabout work zone. Travelers can expect wait times of up to 15 minutes during peak commute hours.
There is a temporary speed limit reduction from 55 mph to 25 mph between milepost 42.4 and 42.5 through the life of the project.
208th Street South is closed between SR 507 and 1st Avenue East for up to four months during roundabout construction.
Work hours are from 7 a.m. to 5 p.m. Monday through Friday until construction is completed later this fall.
Construction in stages
Crews will work in stages to build the roundabouts, primarily during daytime hours, from 7 a.m. to 5 p.m. Monday through Friday. Travel lanes will shift as crews finish each section of the project.
Some intermittent weeknight work may occur as needed between 7 p.m. and 5 a.m.
A map of SR 507 and SR 702 in south Pierce County near Spanaway and McKenna. Two orange dots indicate the location of two roundabout projects.
The intersections of SR 507/208th Street East and SR 702/Harts Lake Road South have a history of collisions. As a result, WSDOT conducted a pre-design study of these intersections. Following the study, crews will build roundabouts at these intersections.
Average daily traffic count during 2024:
- SR 702 - 8,500 ADT
- SR 507 - 16,000 ADT
Why Roundabouts?
Low travel speeds – Drivers slow down and yield to traffic. Speeds in the roundabout are between 15 and 20 miles per hour. The few collisions that occur in roundabouts are minor. Roundabouts also reduce the severity of injuries since they occur at low speeds.
No light to beat – Roundabouts promote continuous flow of traffic. Drivers yield to traffic before entering a roundabout. If there is no traffic in the roundabout, drivers are not required to stop. Drivers don't have the incentive to speed up to try and "beat the light".
One-way travel – Curved roads and one-way travel eliminate the possibility for T-bone and head-on collisions.
Roundabouts instead of traffic lights
The history of collisions at this location are typically T-bone crashes. A traffic signal doesn't eliminate the possibility of those types of collisions. A traffic signal may also increase the number of rear-end crashes. Roundabouts also help promote traffic flow.
Semi-trucks and roundabouts
Roundabouts on state highways accommodate semi-trucks. These roundabouts will have a mountable curb and truck apron. The curb and apron act as an extra lane for semi-trucks hauling trailers. The back wheels of the truck can ride up on the curb and apron to complete the turn.
Engineers consider:
- Collision history - The number of collisions, types of collision, speeds, and other contributing factors.
- Intersection operation - Current and projected travel delay and backups when comparing a traffic light, stop sign or a roundabout.
- Cost - This goes beyond construction costs. The considerations include requirements to buy land and long-term maintenance expenses.
