This project is a part of the Capital Southeast Connector, a regional collaboration to improve roadways. Construction on SR 99 at Grant Line Road in Sacramento involves realigning and raising the highway above active rail.

Once the overpass and new rail line is complete freight and passenger rail traffic will be diverted to the new line without down time. This is made possible by installing lightweight cellular concrete beneath the existing and new rail line. The self-compacting properties of cellular concrete allowed crews to backfill beneath active rail while coordinating install around utilities and structure abandonment.