State Route 4 Wagon Trail Realignment Project


As a major east-west connector through southern Calaveras County, State Route 4 (SR 4) provides access from the San Joaquin Valley to the Sierra Nevada Mountains. Within the County, the two-lane highway traverses mostly rural farmland, characterized by a rolling terrain that supports rock outcroppings, seasonal streams, and natural vegetation, as well as agricultural operations. While much of SR-4 within Calaveras County has been improved in accordance with current design standards, the segment of SR 4 between Copperopolis and Angels Camp does not meet current design standards. The existing facility has the following features:

  • Pavement width varies between 18 to 20 feet for most of the roadway.
  • Shoulder widths vary from 0 to 4 feet with most of the project having no shoulders, except for the 0.6-mile, 40-foot-wide section near the Pool Station Road intersection.
  • Access to State Route 4 is currently uncontrolled. Vehicles can enter or exit the facility from connecting private driveways, commercial driveways, city streets and county roads.
  • The horizontal and vertical alignments follow the existing rolling topography, resulting in numerous curves and limited sight distance.

These features, combined with the traffic volumes, reduce the operating speed of the roadway and do not meet current highway design standards throughout this segment.


To enhance safety, improve sight distance, and limit access to State Route 4, the Calaveras County Department of Public Works, in coordination with Caltrans and the Calaveras Council of Governments (CCOG), is proposing to move forward with a project to realign the segment of SR 4 between Angels Camp and Copperopolis.

Project Description

The State Route 4 Realignment Project will improve the segment of State Route 4 from Bonanza Mine Way to Stockton Road from 2.6 miles east of Copperopolis to about 1.6 miles west of the State Route 4/49 junction in Altaville (Angels Camp), post miles 10.3 to 16.4, a total of about 6 miles. The project will to construct a new alignment with two standard 12-foot width lanes and 8-foot paved shoulders. The project would improve sight distance by increasing curve radii with the incorporation of longer, smoother curves.

Progress to Date

Caltrans initiated the SR-4 Wagon Trail Realignment Project, completing a Project Study Report/Project Development Support (PSR/PDS) document in April 2001. Subsequently, CCOG and Calaveras County led the effort to obtain project approval and environmental clearance for the project, resulting in the selection of a preferred alignment in December 2016. With an estimated construction cost exceeding $50,000,000, the project will be constructed in phases, and based on accident data, the 2-mile segment between Bonanza Mine Way and Appaloosa Road (Phase 1 – Westerly Segment) was identified to have the highest priority.

Next Steps

The Westerly segment from Bonanza Mine Way and Appaloosa Road has been advanced to the Final Design and Right of Way Acquisition phase. During this phase, construction plan sheets and specifications that describe how to build the project will be developed. In addition, right of way will be acquired, utility relocations (if any) will be coordinated, and permits will be obtained.

Once the construction plans and specifications are finalized, the necessary right of way is purchased, and the funding is in place, construction of the funded segments will commence.

Project Schedule

Following is the anticipated schedule of project milestones specific to the western project segment:

  • Design of Western Segment Begins—Feb 2019
  • Complete surveys/geotechnical investigations—August 2019
  • Right-of-Way Appraisals/Acquisitions— 2020/2021
  • Construction (Pool Station to Appaloosa) —2021/2022


Funding is available through State and Federal sources including SHOPP funds, the STIP Regional Improvement Program, and High Priority Projects. Funding is currently secured for the following expenditures:

  • Design: Bonanza Mine Way to Appaloosa Road
  • Right of Way: Bonanza Mine Way to Appaloosa Road
  • Construction: Pool Station Road to Appaloosa Road

Funding for subsequent segments of the project will be requested in accordance with the project’s programming schedule.

Exhibits and Documents

Exhibits and documents prepared for the project to date can be viewed at the following website:


Mimi Huie, Project Manager

Caltrans District 10

1976 Dr. Martin Luther King Jr. Boulevard

 Stockton, CA 95205

Phone: (209) 948-7972



Robert Pachinger, Deputy Director

Calaveras County Public Works

891 Mountain Ranch Road

San Andreas, CA 95249

Phone: (209) 754-6402



Warren Alford, Public Information Officer

Caltrans District 10

1976 Dr. Martin Luther King Jr. Boulevard

Stockton, CA 95205

Phone: (209) 948-3849



Amber Collins, Executive Director

Calaveras Council of Governments

444 E. Saint Charles Street/Hwy 49

San Andreas, CA 95249

Phone: (209) 754-2094