Bridge fire in Hesperia

San Bernardino County firefighters douse hot spots amid the devastated remains of the Ranchero Road overpass on Interstate 15 in Hesperia.  (Gina Ferazzi / Los Angeles Times)

Sparks fly as workers cut through twisted metal and rebar as cleanup of the collapsed Ranchero Road overpass on Interstate 15 in Hesperia begins.  (Gina Ferazzi / Los Angeles Times)

Northbound lanes of Interstate 15, left, are stacked up as traffic is diverted at Ranchero Road in Hesperia, while southbound vehicles diverted in the other direction merge back onto the freeway headed to Los Angeles.  (Gina Ferazzi / Los Angeles Times)

Oscar Avilia of Security Paving heads back to a smoky, ash-covered worksite after getting a fresh breathing mask during cleanup of the collapsed Ranchero Road overpass on Interstate 15 in Hesperia.  (Gina Ferazzi / Los Angeles Times)

A worker from Security Paving gives directions at the collapsed Ranchero Road overpass on I-15 in Hesperia.   (Gina Ferazzi / Los Angeles Times)

The Ranchero Road overpass continues to smolder on Tuesday as crews work to clear mangled and burned rebar after the bridge caught fire a day earlier.  (Gina Ferazzi / Los Angeles Times)

Mounds of fallen steel and wood hover above workers on Tuesday as they try to clear the debris after the under-construction Ranchero Road overpass caught fire above the 15 Freeway in Hesperia on Monday.  (Gina Ferazzi / Los Angeles Times)

Mangled rebar hangs from cement columns on Tuesday as workers clear the ruined Ranchero Road overpass.  (Gina Ferazzi / Los Angeles Times)

Crews on Tuesday manually clear mangled and burned rebar from the destroyed Ranchero Road bridge over the 15 Freeway.  (Gina Ferazzi / Los Angeles Times)

Crews work on Tuesday to clear mangled and burned rebar after the Ranchero Road overpass bridge caught fire on Monday.  (Gina Ferazzi / Los Angeles Times)

A San Bernardino County firefighter makes his way down a dirt slope on Tuesday while monitoring the smoldering Ranchero Road overpass as workers clear debris.  (Gina Ferazzi / Los Angeles Times)

Workers on Tuesday remove debris by hand from the burned Ranchero Road overpass at the 15 Freeway.  (Gina Ferazzi / Los Angeles Times)