City of San Carlos - PG&E Inspection of Pipeline 147


PG&E Inspection of Pipeline 147

Home > ... > PG&E Pipeline 147 > PG&E Inspection of Pipeline 147

PG&E Inspection of Pipeline 147

SAN CARLOS, CA – May 20, 2015 – As part of its ongoing safety work in San Carlos, and at the urging of the City, PG&E initiated an inline inspection of the entire length of natural gas Pipeline 147, from its starting point on Commercial Street to its end point off Edgewood Road in March. The purpose of the inspection is to verify the integrity of Line 147.

PG&E began the safety inspection process by running a calibration tool through Line 147. The tool was unable to move properly through two sections of the line due to the orientation of the pipe. For the inspection to be fully successful, PG&E determined that two sections of the pipeline needed to be reengineered with new “elbows” installed to smooth out the transition and allow the tool to travel through the line. For this to occur, the line was excavated in two sections – at the west-bound lane of Brittan Avenue at Alameda de las Pulgas and in the wooded area between Brittan Avenue and Tasker Lane. When the pipe near Tasker Lane was uncovered, unexplained bulges were discovered. PG&E reduced the pressure in the line, and the section of pipe was removed and sent to Houston, Texas for testing.

In the meantime, PG&E is continuing retrofit work. The line is currently operating at a low pressure (less than 110 psig). When the results of the testing of the damaged pipe are known and when the CPUC authorizes an increase in pressure, PG&E hopes to resume the inline inspection process of Line 147. The inspection will include running another device called a “smart pig” through the line. PG&E’s “smart pig” tool is equipped with a variety of sensors allowing engineers to analyze the interior condition of the pipeline.

For questions or concerns about the details of this project, please call PG&E service representative Austin Sharp at (650) 730-4168 or send an email to