California Department of Transportation

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District 8 Address:
Caltrans District 8
Attn: Public Affairs
464 W. 4th Street
San Bernardino, CA 92401

District 8 Telephone:
Toll-Free: (866) 383-4631
Main: (909) 383-4631
Fax: (909) 383-1009



Projects | San Bernardino County | SR-18 Planned Project

Project: State Route 18 Shoulder Widening and Rumble Strips

pdf gifClick Here for Newspaper Ad (English)
pdf gifClick Here for the Initial Study with Proposed Mitigated Negative Declaration

The California Department of Transportation (Caltrans) plans to widen the existing shoulders and construct centerline and shoulder rumble strips in each direction on State Route 18 and United States 395 junction to 0.9 miles west of Oasis Road, from post mile 101.5 to 11.59, in and near the City of Adelanto in San Bernardino County, California.

The purpose of this project is to address safety concerns caused by motorists who drift from lanes.

Caltrans is the lead agency under the California Environmental Quality Act (CEQA) for this project. Caltrans is also the lead agency under the National Environmental Policy Act (NEPA) for this project.


The Environmental Document for this planned project (an Initial Study / Categorical Exclusion [IS/CE]), as well as the related Technical Studies, are available for review and copying at:

Caltrans District Office (464 W 4th Street, San Bernardino, CA 92401) on weekdays from 9 am to 4 pm.


If you would like to make a comment on the IS/CE or regarding the planned project in general, your comments will be part of the public record. Written comments are due by Friday, May 4, 2018, and should be sent to:

Gabrielle Duff
Senior Environmental Planner
California Department of Transportation
464 W. Fourth St., 6th Floor Mail Station 827
San Bernardino, CA 92401-1400
Send comments via email to:

Please use “SR 18 Shoulder Widening and Rumble Strips Project” in the subject line of the email.

Please be sure to send comments by the deadline: May 4, 2018.


For the proposed project, a Build Alternative and a No-Build Alternative were evaluated in conjunction with preparation of the Initial Study / Categorical Exclusion.

Build Alternative

The major project feature of the proposed Build alternative is to widen the existing SR-18 roadbed to provide 8-foot shoulders in both east and westbound directions and install shoulder
rumble strips along the widened shoulders. The proposed Build alternative also includes removal and replacement of Aggregate Concrete dikes at spot areas within the project limits.
The installation of new guardrail along culvert and power pole areas, where clear recover distance is not achievable, is also proposed. The widened roadbed will require extending
and/or replacing cross culverts within project limits. Construction activities will consist of saw-cutting edge of travel way and constructing 8-foot shoulders. The pavement thickness of the new shoulders will be 0.10-foot of Rubberized Hot Mix Asphalt (RHMA) over 0.50-foot of Hot Mix Asphalt (HMA type “A”) and 0.35 Aggregate Base (AB) - Class 2. The embankment slope will be constructed at 4:1 or flatter.
Approximately 169 partial acquisitions of private property are needed to accommodate the widened roadbed.

No-Build Alternative

Under the No-Build alternative would maintain the facility in its current condition. No improvements or construction activities would be implemented. The No-build alternative would not require any property acquisition or need to relocate utilities.