After a delayed start date, PG&E will begin to prepare this week for testing its natural gas transmission pipeline that runs through Palo Alto, according to Debra Katz, acting communications manager with the City of Palo Alto Utilities Department.
Staging and excavation preparations will begin "possibly as early as Monday or Tuesday," Katz said. The project is expected to continue for two months.
Testing will not disrupt service, as an alternate source will temporarily provide all necessary gas, according to the Utilities Department website. But residents should expect to see above-ground signs of testing such as detours, traffic cones, testing equipment and machinery, as well as notice "noise and some gas smell," Katz said.
Last month, PG&E announced it would be conducting hydrostatic pressure-testing on its gas lines in order to "validate a safe operating pressure for the pipeline and ... reveal weaknesses that could lead to defects and leaks." Hydrostatic tests involve running water through the pipeline at a much higher pressure than it will ever operate with natural gas.
The pipeline is divided into two sections, known as T-29 and T-30. T-29 starts at Alma Street and zigzags south to Middlefield Road. T-30 starts at the intersection of Alma and Page Mill Road and goes up Page Mill to Foothill Expressway.
Staging and excavation will be carried out on both sections of pipe simultaneously, though T-29 will be tested first on Aug. 15 and T-30 "a week or two later," Katz said.
Dig sites for the T-29 section of pipe are located at 2573 Alma, 3672 Middlefield and 3860 Middlefield. Dig sites for T-30 will be located 500 feet north of the intersection of Page Mill and Foothill Expressway and at 650 Page Mill, 925 Page Mill and the corner of Page Mill and Hanover Street.