The new metering system on Mercer Street ramps to I-5 isn’t working quite as efficiently as the state hoped. But the system isn’t the problem.

Chokepoints: Milestones on the horizon for I-5 project

One month of testing the ramp meters from Mercer to I-5 on weekends apparently wasn’t enough prep time for drivers. The state pushed back the date weekday traffic would be metered to April 17, originally scheduled for April 10.

“We observed on Saturdays and Sundays that drivers heading northbound onto I-5 were hesitant to use the left lane,” the state wrote on its website.

Pushing back the date will give driver more time to become aware of the change and give the state time to install additional signage. The state will install an electronic sign on the northbound ramp to “further alert drivers” that they can use both lanes on the ramp to I-5. Temporary signs for both north and southbound ramps will be installed to alert drivers of the change.

The meters on the north and southbound ramps were activated on weekends since early March. It was supposed to have an immediate positive impact on I-5.

“We should see the number of crashes go down about a third and we should see the volume through the area go up maybe three to five percent,” State traffic engineer Morgan Balogh said.

The change isn’t expected to have much — if any — impact on Mercer Street itself.

The goal of ramp metering is to create a safer and easier merge onto I-5. Travel times for drivers on I-5 are also expected to improve.