Power lines are part of the fire environment, especially in the wildland-urban interface. They are a recurring cause of wildfires in California, and along the coast, where lightning fires are rare, power lines are one of the most common ways that wildfires start. For example, power lines were the ignition source for several recent fires in the S.F. Bay Area:
Fortunately, these fires did not start under extreme weather conditions and were quickly suppressed.  
 
Power Line Fire Prevention Field Guide has been developed for California which includes the public resource code requirements designed to prevent power line fires.  The introduction sets the stage for understanding how high winds, in combination with power lines have led to some of California's largest wildfires.
 
Read more about power lines and wildfires in the National Park Service's July 2013 "Fire and Fuel News."