Richardson Grove Improvement Project

US 101 highway shield. Text reads Richardson Grove Operational Improvement.


Caltrans proposes to make minor adjustments to the roadway alignment of Route 101 through Richardson Grove State Park. This project will allow access by industry standard-sized trucks conforming to the Surface Transportation Assistance Act (STAA), which are currently prohibited north of Leggett.

Purpose and Need

Route 101 is the primary north-south route serving the north coast of California and is critical to the commerce of the region. Route 101 through Richardson Grove is a narrow two-lane road with large old growth redwood trees adjacent to the traveled way.

Industry standard-sized trucks conforming to the Surface Transportation Assistance Act (STAA) are currently prohibited from traveling Route 101 north of Leggett due to the narrow alignment at Richardson Grove. This location is one of the few remaining areas of the state in which these trucks are not permitted. As STAA trucks have become the national standard, communities with routes unable to provide STAA access are at an economic disadvantage. Truck cargo must be unloaded and transferred to shorter trucks, making goods movement more expensive.

The truck restrictions at Richardson Grove are due to the tightness of the curves, making it difficult for longer trucks to stay within the traveled way. The 1.1 mile stretch of Richardson Grove is the only remaining location on Route 101 restricting access of STAA trucks traveling into Humboldt County from the south.

This project will adjust the roadway alignment to accommodate STAA truck travel through Richardson Grove. Improvement of goods movement will help local businesses stay competitive in the marketplace.

Project Construction

  • Date to be determined

Public Notice

The 2017 Addendum to the Final Environmental Impact Report is being circulated for public review and comment. The 2010 Final EIR is being provided for background and context only (see documents section below). Written comments on the Addendum will be accepted through November 19, 2021. Comments may be mailed to Caltrans, Attn: Environmental Management, P.O. Box 3700, Eureka, CA 95502 or emailed to

Public Notice - Announcement of Availability (PDF 206K)

Addendum to the Final Environmental Impact Report - May 2017 (PDF 746K)


Accessibility Assistance: Caltrans makes every attempt to ensure our documents are accessible. Due to variances between assistive technologies, there may be portions of this document which are not accessible. Where documents cannot be made accessible, we are committed to providing alternative access to the content. Should you need additional assistance, please contact us at (916) 654-2852 or visit Contact Caltrans District 1 (707) 445-6600 for information about this project. 


Supporting Documents

Responses to Comments on the Supplement to the Final Environmental Assessment, January 2014

Supplement to the Final Environmental Assessment and Final Tree Report, September 2013

Final Environmental Impact Report/Environmental Assessment and Programmatic Section 4(f) Evaluation, May 2010

Photo Simulations

United States Fish and Wildlife Service's Biological Opinion, 2009

Feasibility Study for a 4-lane Freeway/Expressway, September 12, 2001

For more information, contact:

Environmental Management
(707) 445-6583, TTY 711

Media Inquiries - PIO
Myles Cochrane
(707) 498-4272, TTY 711