I-10 Auxiliary Lane Addition Caltrans EA 49750

When completed in May 2012, this project will add 5 miles of auxiliary lanes to Interstate 10 (I-10) between Etiwanda and Riverside Avenues in San Bernardino County.  The $12 million project will provide safety and operational improvements on I-10 between Ontario and Rialto by providing an additional lane for weaving between merging and diverging mainline traffic.

This project was designed to complement interchange reconstruction projects along the I-10 corridor, including projects at Riverside, Cedar, Citrus and Cherry Avenues.  When all five projects are completed, there will be continuous auxiliary lanes in both directions of I-10 between Cherry and Riverside Avenues, which is approximately 7 miles long.  This project will provide a much needed weaving lane as well as a storage for traffic exiting I-10, which is now forced to queue in the outer mixed flow lane of the mainline, which causes additional congestion on the adjacent mainline lane.  This project utilized a retaining wall to achieve the auxiliary lane addition between Riverside and Cedar Avenues, which eliminated the possibility of a costly drainage channel reconstruction and kept the project within budget.

The project utilized Proposition 1B Corridor Management Improvement Account funds for development and construction.  This project also utilized Proposition 1B funds, which put strict deadlines on project delivery, and was achieved as originally scheduled.  The Southtstar project manager worked closely with all District 8 functional units to deliver the PA/ED, PS&E and Right of Way phases on-time and within the support budgets programmed for the project. This enabled the project to move to construction when funds became available.

Project Owner
State of California – Department of Transportation (Caltrans)
Point of Contact Name
Robert So
Point of Contact Telephone Number