With Whatcom County moving forward with the installation of a $3.8 million roundabout at the intersection of Birch Bay-Lynden Road and Blaine Road, some residents are questioning whether a roundabout is the best choice for the busy intersection.
When Birch Bay resident Henry Wernecke learned of the project, he had concerns about the impact a roundabout might have on traffic.
Wernecke, who’s lived in the area for about 10 years, drives through the intersection at least once a week on his way to the grocery store. He said he’s glad that the intersection is getting some kind of upgrade, as the four-way stop is a hassle.
Traffic can pile up quickly at the intersection, he said, especially during busy weekends and holidays.
His main concern is that during busy times, a constant stream of traffic from Birch Bay-Lynden Road could make it difficult for drivers on the less busy Blaine Road to enter the roundabout, he said.
“Once you get a line of traffic, they don’t let anybody in,” Wernecke said of his experience with roundabouts.
Wernecke said he typically prefers traffic signals over roundabouts. He was one of two Birch Bay residents who submitted letters to the editor regarding the roundabout. Both asked whether the county considered a stoplight.
Whatcom County Project Engineer Andrew Tischleder said that the county did consider a traffic signal alternative, but the roundabout won out for a few reasons.
One reason was safety. Tischleder said studies show that roundabouts are safer than traffic signals.
“The main benefits are that a roundabout slows down vehicles approaching the intersection and reduces conflict points. A traffic signal allows some vehicles to travel through the intersection at the posted speed limit (45 MPH at this intersection),” Tischleder wrote in an email.
He continued, “A roundabout, on the other hand, slows vehicle speeds down to 15 mph through geometry, creating a safer environment for both vehicles and bicycles and pedestrians.”
He cited a study titled “Roundabouts: An Informational Guide,” which found that head-on and T-bone collisions are mostly eliminated with roundabouts. Roundabouts also limit high-speed collisions. The referenced study can be found on the county’s website at: bit.ly/4yxzfY1
Tischleder also said the safety of pedestrians and cyclists played a role in choosing a roundabout over a stoplight.
Neither option would have had a dedicated lane for bicycles, he said.
Because a roundabout reduces drivers to 15 mph, that makes it safer for pedestrians and cyclists looking to cross the roads, Tischleder said, though he noted that the intersection doesn’t currently see much use by pedestrians or cyclists.
Wait times were another factor in the county’s decision to go with a roundabout, Tischleder said.
Based on a 2021 study conducted by the county, it takes vehicles an average of 18 seconds to get through the intersection during peak-traffic on weekdays, but if the intersection were to remain a four-way stop, that time would increase to 105 seconds by 2045.
Whatcom County’s Comprehensive Plan projects that by 2045, Birch Bay’s population will increase by 2,662 from its 2023 population, bringing its total population to 11,570. Blaine’s population is expected to increase 3,500, bringing its total to 10,228 by 2045.
The study projected that by 2045, it would take vehicles an average of nine seconds to get through the intersection if a stoplight were installed, while that time will be just seven seconds with a roundabout.
But by 2045, during peak-hour traffic on weekdays with seasonal increases taken into account, it will take drivers 18 seconds with a stoplight, and 10 seconds with a roundabout.
“This information tells us from an operations perspective the signal and roundabout will perform similarly, but that the signal does start to get larger delays as the traffic volumes increase,” Tischleder wrote. “This means the signal is less resilient to population growth in the area.”
Finally, Tischleder said that the cost of installing a roundabout was cheaper than a stoplight.
He said that during the planning phase of the project, construction costs of a roundabout appeared to be about $500,000 less than a traffic signal alternative at this intersection.
The estimated construction cost of the roundabout is about $2 million, he said. Construction is expected to begin in summer 2027.
Washington Traffic Safety Commission Communications Lead Doug Dahl said that in his work writing weekly traffic safety articles, he gets asked about roundabouts more than any other topic.
Dahl said he thinks a roundabout is a good fit for this intersection, and it's in line with the growing trend of traffic engineers favoring roundabouts over traffic signals.
“If an intersection is busy enough to where a four-way stop is no longer working for it, kind of the default position is: You go with a roundabout unless there’s a reason not to,” Dahl said.
He echoed many of the same points Tischleder mentioned, but safety is where roundabouts really shine. He said roundabouts reduce fatal crashes by about 90%, while also being safer for pedestrians.
Dahl also mentioned that generally, roundabouts greatly reduce vehicle idling, with some intersections saving 30,000 to 50,000 hours more than a traffic signal would.
Because of this, roundabouts are better for the environment and long-term sustainability.
He noted that once installed, roundabouts typically require less maintenance and upkeep than signalized intersections, providing further cost savings.
But to make roundabouts effective, it’s important that drivers understand how to use them properly.
He encouraged people who might feel uncomfortable driving in roundabouts to be open to learning about them. He recommended the state Department of Transportation’s webpage on roundabouts as a good resource for drivers looking to brush up on their roundabout etiquette. The webpage can be found at wsdot.wa.gov/travel/traffic-safety-methods/roundabouts.
Before entering a roundabout, drivers should yield to the people already in the roundabout. Once in the roundabout, drivers should stay in their lane if it is a multilane roundabout, and don’t stop – even if you miss your exit, Dahl said. You can just go around again if needed.
