Mystery markers along highway
A number of people have been wondering what those 10-foot tall signs are that have mushroomed along Sonoma Hwy. and elsewhere in the valley. They are gas pipeline markers, installed as part of PG&E’s comprehensive survey of its 6,750-mile natural gas transmission pipeline system.
The markers, 10-foot poles with an orange and white striped “paddle,” are placed in agricultural areas in particular, and indicate the approximate location of the underground pipeline, serving as a reminder for people to be careful when working nearby. The paddle markers are aimed at providing a more visible line of sight indicator for both landowners and PG&E. The paddle part points downward to the location of the pipeline.
The underground pipeline in this case roughly parallels the highway, then heads down Dunbar Road, through Sonoma Valley Regional Park, and back up to Arnold Dr. near the Sonoma Developmental Center. Then the pipeline heads down Arnold Dr., crosses over at Agua Caliente Road back to Sonoma Hwy., and keeps heading into Sonoma and beyond.
You can view a map of PG&E’s natural gas pipeline transmissions by going to www.pge.com/pipelinelocations.
PG&E says that damage from excavation is a common cause of pipeline accidents, so anyone who plans on digging for a new septic or well system, or planting new vineyards or other crops, should call 8-1-1 at least 48 hours in advance. 8-1-1 is the phone number for Underground Service Alert, which then notifies underground utility operators, like PG&E, of the work being planned.