The Steptoe roundabout is breaking new ground once again.
Tuesday afternoon, the Washington State Department of Transportation will turn on a new traffic meter on westbound Columbia Park Trail. The new signal is about 100 yards from the roundabout entrance.
It is Washington’s first permanent traffic meter at a roundabout.
The stop-and-go light should make it easier for drivers leaving eastbound Highway 240 to enter the roundabout by creating “gaps” between vehicles in the roundabout.
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That should minimize the evening backups that breed dangerous traffic conditions on the off-ramp.
“We’re very excited,” said LisaRene Schilip, a DOT traffic engineer working on the Steptoe update.
A win for public safety
Steptoe debuted in 2007 at the intersection of Columbia Park Trail, Steptoe Street and the Highway 240 off-ramp.
It replaced a four-way intersection that had several fatal wrecks and, during rush-hour, backed up onto the highway.
The roundabout draws plenty of criticism, but there have been no deaths. Engineers consider it a win for public safety.
The most serious collision was two years ago, when an impaired driver lost control of his car going about 100 mph.
The young driver careened through the intersection and destroyed his car. He ended up pleading guilty to drug charges. Most importantly, he survived.
Still, the original two-lane configuration confused drivers so much that it led to calls for DOT to rethink the design. There were 129 fender-benders between 2011 and 2013.
DOT narrowed the Columbia Park Trail approaches to a single lane in 2016.
Today, 35,000 vehicles pass through each day. Traffic peaks at 3,300 per hour during the evening rush, with 1,200 coming off the highway, commuters headed home — many from the Hanford nuclear reservation.
Engineers have seen cars waiting on the off-ramp for up to 2 minutes and 15 seconds.
The backups extend the entire length of the off-ramp -- shortening or eliminating the slowdown zone. That creates dangerous conditions, with vehicles going at highway speeds suddenly coming up to slow-moving off-ramp traffic.
That’s the problem engineers want to solve.
How it works
The $100,000 traffic meter and associated equipment are in place and ready to go. An engineering crew will calibrate the system Tuesday and turn it on.
Sensor “loops” embedded in the off-ramp will detect stopped traffic and activate the red-green meter on Columbia Park Trail.
When the meter is active, westbound drivers on Columbia Park Trail will have to wait for a “green” to proceed to the roundabout entrance.
A green light is not free admission to the roundabout. Drivers must still follow the roundabout rules, which includes yielding to traffic approaching from the left and semi trucks which turn wide and can’t stop quickly.
Schilip said the meter is programmed to come on when traffic is backed up. It should only work during the afternoon peak.
“We don’t want it turning on and off all day long,” she explained.
It should come on during the Monday to Thursday evening commute. Friday is a non-work day for Hanford, so traffic isn’t as congested.
A “Ramp Metered When Flashing” sign alerts Columbia Park Trail drivers to the coming signal. The alert is near the spot where the road passes beneath Highway 240, near the Ben Franklin Transit headquarters.
It is unclear what if any relief the meter will offer other drivers, such as those driving east on Columbia Park Trail or south on Steptoe.
Officials hope the added “gaps” will help all sides of the intersection.
Morning backups on Steptoe and Columbia Park Trail are common and even annoying. But engineers say they’re less critical because they don’t mix high-speed highway traffic with slowing drivers.
But if the traffic meter is a success, DOT may consider replicating it on other sides to speed up morning traffic.
In the interim, South Richland residents can avoid Steptoe by using the newly renovated Queensgate Drive to access Interstate 182 and Highway 240.
The city of Richland recently updated the southern stretch of Queensgate. The road, complete with roundabouts at I-182 and Columbia Park Trail, opened in August.