We're in the final stages before crews make major modifications to the I-5/Marvin Road overpass in Lacey. During fall 2018, workers will begin construction on a project that will benefit all users of the overpass. This is not just about cars and trucks. Bicyclists and pedestrians also will benefit.
The existing overpass will be converted into what's called a diverging diamond interchange. This type of interchange, while new to Washington, has proven effective in other states across the country. This upgrade is also a cost effective improvement for the growing community.
One of the key benefits to improve traffic flow is a free left turn onto I-5. Because drivers are directed to the left side of the road, there is no need to wait at a traffic signal before turning onto the highway on-ramp.
How to bicyclists and pedestrians use it?
This new interchange accommodates both pedestrians and cyclists. In addition, cyclists also get a choice. They can use bicycle lanes going in both directions or they can follow the pedestrian route that uses a series of crosswalks. There also will be a protected divider in the middle of the overpass where both bicyclists and pedestrians can travel.
This interchange is designed to be intuitive. Drivers will do what they already do: Follow the signs and lines. There will be clear lane markings and traffic lights that will guide drivers through the new interchange.
Let's take a look through these virtual drive throughs.
We plan to keep traffic moving by doing a majority of the work at night where possible. There also will be extended periods of time when the overpass will have narrowed, reduced, and shifted lanes. Drivers can also expect short-term and long-term ramp closures. Closures will be announced as they are scheduled.
We will announce these via a distribution list to provide advance notification of construction. We encourage all users of this interchange to self-subscribe. The work is expected to be complete in about two years.