BOULDER CREEK (CBS SF) — Nearly two months after dry lightning strikes ignited a massive wildfire that swept through the Santa Cruz Mountains, evacuation warnings for the fire-ravaged Boulder Creek neighborhoods have finally been lifted, officials said.
Cal Fire announced late Thursday that all warnings have been removed for areas in Santa Cruz County.
“Boulder Creek residents served by Big Basin Water Company need to monitor water quality tests” were the final words of caution issued by fire officials.
The lightning-sparked fire broke out on August 16, and charred more than 86,000 acres in San Mateo and Santa Cruz counties, an area spanning some 135 square miles.
One person died in the fire, thousands forced to evacuate and 925 homes were destroyed in Santa Cruz and San Mateo counties.
With the showers in the forecast for Friday and the rainy season beginning in the Bay Area, there were new concerns over possible mudslides and debris flows in fire scarred regions of the mountains.
Debris flows, essentially massive landslides, are triggered after high-intensity but short-duration bursts of rain. Short can mean as little as 15 minutes of heavy rain fall.
While landslides have always been a threat in steep, hilly areas of the Santa Cruz Mountains; the threat has been exacerbated in and around burn areas following the CZU Fire.
The fire burned away flora and their roots, leaving loose soil and rocks that, when saturated by rainfall, create a moving mass that can travel over 30 miles per hour, or at avalanche speeds.
“The debris flow threat affects not only homes on hillsides or within the burn area, but also homes on flat ground a mile or more from charred slopes,” county Senior Civil Engineer Carolyn Burke said during a late September presentation to the Board of Supervisors.