February 13 - March 18, 2023 Drilling Will Close Sawyer Camp Trail
A team of engineers are drilling holes through portions of the San Andreas Dam to obtain core samples for further investigation. This drilling will require the closure of Sawyer Camp Trail from the North Gate at Hillcrest Blvd. to the Jepson Laurel. The trail will be closed every day.
Core Analysis and Model Building
The cores extracted will be about 3-inches in diameter. They will be used to determine the content of the bedrock and fill used to create the layers of the earthen dam. Once the analysis is made and the layers determined, the engineers will create a 3-D model of the dam. This model will be used to see if previous earthquakes have weakened or changed the characteristics of the dam in ways that will need to be corrected. Also, the model can predict if the current conditions will need to be supplemented in order to prevent future problems due to earthquakes or other natural disaster.
While the sampling will take just a few weeks of activity, the evaluation effort will extend for several years.
PG&E Gas Transmission and Other Projects Requiring Trail Closures through February 24, 2023
PG&E is excavating a portion of the San Andreas segment to inspect the subsurface gas transmission line and to install new monitoring and reporting devices.
For up-to-date information on trail closures, visit San Mateo County Park's Website.
