Scale of widening project apparent in quantities required to complete it

The I-405 Sepulveda Pass Improvements Project is a large project by any measure: its length, its cost, its complexity. Another measure of its size is the amount of materials that will be required to complete the 10-mile-long project.

How much material?

• There will be 37,000 cubic yards of new concrete in the bridges alone.
• There will be 800,000 cubic yards of earthwork excavation.
• There will be 300,000 cubic yards of earthwork backfill.
• There will be 109,000 cubic yards of new concrete pavement.
• There will be 76,000 tons of new asphalt pavement.
• There will be 50,000 linear feet of new drainage pipes.
• There will be 1,000,000 square feet of new retaining walls.
• There will be 247,000 square feet of new sound walls.

If the drainage pipes were laid end-to-end, for example, their length is equal to approximately 139 football fields.

The 76,000 tons of new asphalt pavement would create thousands of asphalt driveways. For comparison, assuming an “average” driveway is 500 square feet and three inches thick, that driveway would require nine tons of asphalt pavement, according to Kent R. Hansen, P.E., Director of Engineering, National Asphalt Pavement Association.

That equals 8,444 driveways—more than enough to build a driveway for each man, woman, and child in Ojai, California.

Ned Racine