State of California • Department of Transportation
NEWS RELEASE
Merced
Caltrans Receives 2025 San Joaquin Valley Blueprint Award for State Route 99 Plainsburg-Arboleda Mammoth Silhouettes
Merced – The California Department of Transportation (Caltrans) has received an Award of Excellence for Historic Preservation at the 2025 San Joaquin Valley Blueprint Planning Process Awards.
Caltrans District 10 received this year’s Historic Preservation Award in recognition of the Plainsburg-Arboleda Columbian Mammoth Silhouettes project that were installed across the Plainsburg Road and Le Grand Road overpasses on State Route 99 in Merced County.
In 2009, the eight regional planning agencies in the San Joaquin Valley came together in an unprecedented effort to develop a coordinated valley vision – the San Joaquin Valley Regional Blueprint. This eight-county venture know as the San Joaquin Valley Regional Policy Council have formed a preferred vision for future development throughout the Valley to the year 2050. To recognize construction plans, policies and projects that are “Blueprint friendly”, the Valley’s regional planning agencies created an awards program specifically designed for this purpose.
During construction of the original State Route 99 Plainsburg-Arboleda freeway project in 2012 nearly 1,000 Ice-Age fossils were discovered near the Plainsburg and Arboleda Road intersections including the Columbian Mammoth. In alignment with Caltrans steadfast commitment to the preservation of historical artifacts, the agency was firmly committed to finding a permanent home for the fossils here in the Central Valley at UC Merced where future generations could view and learn about the discovery.
The nearly $5 million Plainsburg-Arboleda Mammoth Silhouette project was then initiated not only to mitigate the paleontological impacts but also to foster a connection between the freeway project and fossil discovery along with increasing public curiosity and awareness of the region’s rich natural history.
Motorists should expect 5-to-10-minute delays and use alternate routes whenever possible. All work is scheduled to occur as listed but is subject to change due to traffic incidents, weather, availability of equipment/materials, and construction-related issues.
For the safety of workers and other motorists, please Be Work Zone Alert. For the latest highway conditions, visit quickmap.dot.ca.gov
