The West Valley Fault Line in Laguna begins by crossing the Tunasan River at the boundary of Muntinlupa and Laguna. Several fault lines are formed commencing from Susana Heights Estate then traversing La Marea and and splitting into two fault lines north and west of Alaska Milk Corporation at the South Luzon Expressway San Pedro Exit.
On a wider scale, West Valley Fault Line in Laguna imperils the town of San Pedro: in Susana Heights, La Marea, Reaville, San Antonio Public Cemetery, United San Pedro Subdivision and Adelina 1-A.
The first fault line starting from the public cemetery passes through Holiday Hill Subdivision; while the second fault line extends from Adelina 1-A to Adelina 1 Complex.
Both lines converge at GSIS Village in the vicinity of New Year Avenue/ Fiesta Boulevard, and another fault line forms at Circle Avenue as it enters Barangay Sampaguita Village.
From Barangay Sampaguita Village, the fault line stretches in to Molave Steet and Ilog San Vicente in Barangay Calendola before reaching Harmony Homes.
Stonecrest is also bisected with several fault lines in and around its area. One is in Purok 5, Barangay Magsaysay, a second one extending from Harmony Homes from the north, a third one from Villa Oympia 6 and finally, one from the south in Juana 3.
San Jose Elementary School, which lies within General Mariano Alvarez (GMA), Cavite, is situated between two fault lines – one within Barangay San Jose that runs through the public market and the second one in Juana 3.
The fault line in Laguna is marked in several areas including portions of Carmona, Cavite which will be presented in the last part of our series.
The West Valley Fault Line in Laguna appears once again in Barangay Biñan, Biñan, Laguna crossing Ayala Westgrove Heights and portions of South Forbes Gold City which is part of Silang, Cavite, then skirts back to Sta. Rosa, Laguna. It intersects at Sta. Rosa – Tagaytay Road near the Santo Domingo National High School.
The final extension of the West Valley Fault Line in Laguna is found in Calise in Cabuyao, north of Canlubang Golf & Country Club. It passes along the left side of the park and ends at Mabato near Riomonte in the west side of Calamba.