Wednesday, December 22, 2010

City of Sierra Madre Responds to Debris and Mudflows

City of Sierra Madre Responds to Debris and Mudflows

Portions of the Sierra Madre have experienced small mudflows this afternoon in the northern most portions of the canyon. Public Works crews are prioritizing tasks to address situations to protect life and property first. Crews will work to clear public roads when it is safe to do so and equipment can be effectively used.

The National Weather Service has issued a Flash Flood Warning for areas including the City of Sierra Madre. This Warning is in effect until 6:00pm this evening. Residents are instructed to not drive any vehicle into areas where the water covers the roadway. The water depth may be too great to allow your car to cross safely.

The City is currently at Green Flag Alert as the Los Angeles County of Public Works has rescinded their Phase 1 mudflow forecast. Please understand that a Green Flag Alert means that residents should be ready for evacuation and monitor weather developments closely. Very heavy rain and thunderstorms, like the City has experienced this afternoon, can happen with very little warning.

City of Sierra Madre’s Three-Color Flag Alert System:

GREEN FLAG - Activated under a prediction of 80% - 100% chance of precipitation. Affected residents should get “READY” for potential evacuation. This includes keeping a close watch on weather forecasts.

YELLOW FLAG - Activated with an LA County Phase 1 mudflow forecast, or deemed consistent with the County’s forecast thresholds. This is described as small, isolated debris and mudflows possible at specific locations. Affected residents should get “SET” to leave their homes and may choose to voluntarily evacuate. Please note that all vehicles must be off the streets in potential mudflow areas during Yellow Flag alerts.

RED FLAG - Activated with an LA County Phase 2 or 3 forecast. Phase 2 includes moderate debris and mudflows at more widespread locations. Phase 3 - the potential exists for significant debris and mudflows to be widespread. Affected residents should “GO”, meaning they should immediately evacuate, and vehicles should not be parked on the streets.

For more information about mudslide and debris flow preparations, please visit and click “Emergency Preparedness Information” on the home page. Updates will also be issued on SMTV3 (Time Warner-channel 3), Sierra Madre Community Radio (AM 1630), and the City’s Emergency Blog (