Transportation Infrastructure Projects

State Route 54 | San Diego County

This project involved major improvements to a section of the SR-54 freeway at the Reo Drive Overcrossing in San Diego near National City. Grading operations dug into a 30 to 40 foot thick sequence of Pleistocene river deposits that yielded well-preserved fossil remains of turtles, lizards, snakes, birds, and land mammals from over 105 individual discovery sites. The mammal fossils were especially significant and included bones and teeth of rodents, dire wolf, horse, camel, deer, ground sloth, mammoth, and mastodon.

State Route 76 / Interstate 15 Interchange | San Diego County

PaleoServices monitored improvements to the freeway interchange, including bridge widening, addition of loop-on on ramps, and widening of existing on- and off-ramps. Grading exposed a sequence of Pleistocene river deposits that yielded a small assemblage of terrestrial microvertebrate fossils (salamanders, lizards, snakes, and small mammals), as well as the skull and partial skeleton of a giant bison (Bison latifrons). Discovery and conservation of the bison generated local and national media attention for both the Museum and Caltrans.

Brawley Bypass | Imperial County

This project involved construction of the Brawley Bypass—a new four-lane expressway extending from State Route 86 to State Route 111 near Brawley, California. Monitored excavation work included mass grading along the right of way, and excavation of a large borrow site (depicted above). PaleoServices staff discovered and salvaged well-preserved freshwater ostracods, snails, oysters, and bony fish from deposits of early Holocene to late Pleistocene Lake Cahuilla.

Interstate 5 HOV Project Segments 1, 2, and 3 | Orange County

This project involved widening Interstate 5 along a 5.7-mile stretch for the addition of high occupancy vehicle lanes, and reconstruction of the Avenida Pico Interchange. Monitors inspected a diversity of excavations that yielded remains of 5 to 7 million year old marine clams, snails, fish, whales, pinnipeds, and terrestrial plants from the Capistrano Formation, as well as a high diversity assemblage of marine invertebrate and terrestrial vertebrate fossils from approximately 330,000- to 413,000-year-old Pleistocene terrace deposits. The Pleistocene marine invertebrate assemblage was particularly diverse and sampled a range of ancient intertidal and subtidal open coast habitats.