State Route 108 Corridor Map
State Route 108 Corridor System Management Plan (CSMP)
Download the SR-108 CSMP by clicking here
State Route (SR-108) is an east/west principal arterial from its western terminus at the junction of State Route 99 (SR-99) in Stanislaus County (District 10) to Yosemite Junction at East State Route 120 (SR-120), and a minor arterial from Yosemite Junction across Tuolumne County (District 10) to its eastern terminus at the junction of United States (U.S.) Route 395 (District 9). State Route 108 is an important trans-Sierra route connecting the eastern Sierra Nevada region of California with the Central Valley and other parts of the state.
In District 10, SR-108 is unconstructed from Interstate 5 (I-5) near Crows Landing in Stanislaus County to the junction of SR-99/State Route 132 (SR-132). The constructed portion of SR-108 runs from SR-132 in Modesto through Stanislaus and Tuolumne counties to U.S. Route 395 at Sonora Junction in Mono County. SR-108 has concurrent routing along portions of: SR-132 in Modesto; SR-120 between Oakdale and Yosemite Junction; and SR-49 from west of Jamestown to Sonora.
State Route 108 is an important farm-to-market corridor in the San Joaquin Valley. It serves commuter and local traffic in the cities of Modesto, Riverbank, Oakdale, and Sonora. It also serves the unincorporated communities of Jamestown, East Sonora, Twain Harte, Sugarpine, Mi-Wuk Village, Sierra Village, Pinecrest, and Strawberry. It also serves the Dodge Ridge Ski Area near Pinecrest.
Corridor Specific Issues
- Limited parallel roadway capacity
- Lack of right-of-way (“Main Street” highway) and environmental and financial constraints through communities for capacity increasing improvements
- Difficult Context Sensitive Solutions for roadway improvements
- Limited seasonal access due to chain control, snow gate closures, snow removal equipment, and closures due to special events, traffic incidents, and natural causes (i.e. rock slides, fallen trees, etc.)
- Heavy resort/recreational traffic all year long
- Recurrent highway and roadway traffic congestion at particular locations
- Roadways have many irregular horizontal and vertical alignments
- Minimal shoulders widths in many areas, which may restrict safe bicycle and pedestrian/equestrian traffic
- Gaps and barriers within bicycle, pedestrian/equestrian facilities, and crossings
- Limited off-road parking in recreational areas
- Limited formal Park-and-Ride Facilities and Rest Areas
Corridor Mobility Improvement Account (CMIA) Projects
The CSMP requirement is noted in the Baseline Agreements of all projects receiving CMIA funding. CMIA funds have been allocated for the following improvement project on the SR-108 Corridor:
- East Sonora Bypass, Stage 2
