Fire alarm at Grand Terrace High School Heard on: San Bernardino County CA Fire Dispatch 00:09 Commercial fire alarm, medic engine 23 at Grand Terrace High School, 21810 Main Street between Michigan Avenue and Main Street. Transcript This transcript is auto-generated from live dispatch audio and may be incomplete or inaccurate. It is not an official report and may change. Commercial fire alarm, medic engine 23 at Grand Terrace High School, 21810 Main Street between Michigan Avenue and Main Street. 2026-11-06 20:17 UTC Fire Main St, Grand Terrace, CA 92313 View on map