California High Speed Train: A Statewide Geo-Seismic Evaluation using GIS

The California High Speed Train Authority, created by the state Legislature in 1996, plans to provide more than 42 million annual commuters with a means of cross-state travel, reduce highway demands, and improve air quality by creating a statewide High Speed Train (HST) system. The HST will be a 200+ mph (320 km/hr) steel wheel, electric system traveling 750 miles (1200 km) on at-grade, elevated, and underground steel track rails, extending from Southern to Northern California in about 2.5 hours. A backbone infrastructure system of this nature is highly sensitive to environmental factors and requires cautious examination and planning, especially given California's complex geology and seismic activity. Geologic and seismic studies were performed as part of the Program Level Environmental Impact Statement (EIS) for the proposed statewide using a Geographic Information System (GIS). GIS was used to compare statewide geologic and seismic data for the various alternatives. GIS data included geologic formations, active faults, ground motion, soils, oil and gas fields, and mineral resources. Active fault crossings, areas of high ground motion, unstable formations, and large landslides were avoided by realignment where feasible. Tunnel sections were realigned to avoid fault crossings at depth. Mitigation of at-grade active fault crossings and associated ground motion will include speed reduction at crossing and modern ground motion sensors use SCADA (Supervisory Control and Data Acquisition) systems to reduce the possibility of derailment. A request for appropriation of statewide funds for the first segment of the HST project will be placed on the November 2004 ballot for Californians to vote on their future transportation system.