California Department of Transportation

Pine Grove State Route 88 Improvements Project


Project Description
The California Department of Transportation (Caltrans), in cooperation with the Amador County Transportation Commission (ACTC), proposes to modify State Route 88 (SR 88) through the Town of Pine Grove in order to alleviate congestion, improve operations and enhance safety between the intersections at Climax Road and Mount Zion Road. State Route 88 is a principal arterial connecting the San Joaquin Valley with the State of Nevada. SR 88 is part of the National Highway System (NHS), which passes through Pine Grove and serves as the main street to this established foothill community. Increasing traffic volumes on SR 88 have created a need to address the issue of traffic congestion in Pine Grove.

SR 88 through Pine Grove is a two-lane facility with a third lane, or turn pockets, to facilitate left turn movements. Current and projected traffic volumes exceed those deemed by Caltrans and the ACTC to be acceptable traffic capacity service levels for this type of facility. Local residents are also concerned that current traffic is causing significant congestion.

Project components currently being studied include widening SR 88 through the Pine Grove and/or the construction of either a southerly or northerly two-lane bypass route.

Purpose and Need
The purpose of this project is to improve operations on State Route 88 (SR 88) through Pine Grove. Development, both residential and commercial, has added a commuter dimension to the Pine Grove traffic movement. Commuters from Pine Grove are commuting to employment centers in Jackson and beyond. SR 88 is a Terminal-Access Route on the California Truck Network, increasing the requirement to accommodate large semi-trucks. The capacity of SR 88 is constrained by factors that regularly limit rural roadways in the Sierra Nevada, including grade and available passing site distance. This segment is currently experiencing congestion due to increasing traffic volumes on Climax Road, Ridge Road, and Volcano Road. Due to these factors, there is a need to improve traffic circulation in the Pine Grove area.

Level of Service (LOS):
The proposed project is required to address existing and projected traffic congestion in Pine Grove. Existing travel volumes currently result in LOS E at peak periods. Projected increases in traffic volumes will result in an LOS F at peak periods. Caltrans target figure is LOS C in rural areas and LOS D in urban areas (i.e., downtown Pine Grove). Both the existing LOS E and projected LOS F are unacceptable.

Circulation Issues:
Pine Grove has been identified as a “bottleneck” for traffic using SR 88. The resulting congestion concerns both local and regional traffic. The limits of the current project include SR 88 from the intersection with Climax Road to the intersection with Mount Zion Road. Related issues, such as traffic flow on Ridge Road and Climax Road, will affect this project and will need to be examined. Commercial and residential access encroachments throughout the corridor have also been identified as an operational challenge to be addressed within this project. Access to the downtown area of Pine Grove is constricted, causing operational concerns for local as well as regional traffic traveling to destinations outside of the Pine Grove area.

Future Conditions:
The volume of traffic using SR 88 will continue to grow, and congestion will become increasingly severe. There is no existing viable alternative route for most of the traffic using SR 88, and no existing bypass for Pine Grove. SR 88, within the project limits, has experienced increased demand to accommodate additional commuter traffic and large semi-trucks. SR 88 currently carries approximately 19, 600 vehicles per day with about 2,000 vehicles during the peak hour. This is expected to increase to 36,400 vehicles per day (3,600 vehicles during the peak hour) by the year 2028.