For previous day coverage of the fire on the Oceanside Pier, click here
Investigators have ruled out arson as a possible cause of a fire that engulfed the far seaward end of Oceanside Pier last week, causing extensive damage and forcing an indefinite closure of the historic seafront landmark in the northwestern corner of San Diego County.
The massive fire that started last Thursday and continued burning for several days afterwards was completely out by Monday morning, Oceanside fire officials said in a press conference that afternoon.
"There is no more damage being done to the pier," Oceanside Fire Department Deputy Fire Chief Jess Specht said.
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"After this afternoon operationally, we have nothing left to do from a firefighting standpoint, and we will fully transform into the recovery phase," Specht said on Monday.
The flames were completely out by 7 a.m., no smoke, no fire, Specht added. Fire officials could not give a definitive cause of the pier fire by Monday, but it is most likely an accidental cause, said OFD Fire Chief David Parsons.
"No evidence of an incendiary or intentional act was found," Parsons said.
"And everything leads us to believe, based on canine (searches), reports, videos, witness interviews, fire dynamics, which is how fire moves, and then also patterns that we see in the structure ... that an incendiary liquid, which could be indicative of potential arson -- none of that's present," Parsons said.
Investigators are working to determine more about what caused the fire, but at this time cannot rule out an electrical heat source, Parsons said.
Video evidence and witness interviews suggest that the fire started on the northwest side of the pier -- possibly underneath the promenade deck -- next to the former Ruby's Diner site, which was undergoing renovations at the time of the blaze, according to city officials.
More Oceanside Pier fire coverage:
A formal report on the investigation will be released to the public in at least a matter of weeks, but perhaps more, he said.
Just before the fire started, a restaurant on the pier, the Brine Box, was in operation with two people working at the time. Due to it being a small restaurant, they shared some operations with the former Ruby's Diner, a closed down, but not abandoned, restaurant on the pier, Parsons said.
Parsons emphasized that the old Ruby's was not an demolished building.
"Definitely not derelict, definitely not abandoned, just in a closed state awaiting permits and plans to get a new tenant into the space. Smoke alarms did activate in the Ruby's. Sprinkler system did activate in the Ruby's. Again, those are interior life safety systems not designed to stop a fire that's coming from the exterior," Parsons said.
"The fire suppression system that runs along the pier was brand new," Parsons said.
"With that being said, as soon as possible, we are going to reopen the pier to the public, and we should have 75% of this pier back open to the public as quickly as possible," said OFD Division Chief Community Risk Reduction Blake Dorse said.
During an all-out multi-agency effort that continued for more than 24 hours, crews were able to save roughly 95% of the iconic 1,950-foot-long wooden structure, according to city officials. Emergency-services personnel from agencies across the county battled the flames from atop the burning pier, aboard a pair of firefighting boats and in water-dropping helicopters as the blaze sent a towering plume of black smoke to the east. The Coast Guard sent in a cutter to aid in handling the emergency.
Over the course of the around-the-clock firefight, crews put a "trench cut" in the deck, removing a section of it to allow for access to flames burning underneath it and to prevent the blaze from traveling any farther down the pier to the east, the fire chief said.
The city has been working with a contactor on installation of temporary fencing to block off the damaged end of the pier, allowing for a partial reopening during repairs, officials said.
PHOTOS: Fire erupts on Oceanside Pier
Coast Guard-enforced restricted areas around the pier -- 100 yards for vessels and 100 feet for swimmers and surfers -- remained in effect this week.
Exactly when the public will regain access to the tourist-attraction structure remained unclear Monday, though city leaders were committed to reaching that goal "as quickly as possible," Parsons said.
At this time, there is no definite timeline on when the pier will be reopened, officials said.
Oceanside Mayor Sanchez speaks
"There is no other city that could boast this kind of public safety," Oceanside Mayor Esther Sanchez said at the press conference. Sanchez thanked local, state and federal agencies for stepping in to help.
"That is something that I've heard all over Oceanside, that we want her [the pier] back as soon as possible," Sanchez said.
Oceanside City Manager Jonathan Borrego said they expect Oceanside's city council to formally ratify an emergency proclamation this week which would allow the city to expedite its process of getting federal and state reimbursement for the pier.
The wooden structure was first built in 1888 but has been destroyed twice in its lifetime, once in 1890 by rough seas and, after it was rebuilt, again in 1902.
Thursday's fire is not the first building to burn on the site. In 1976, "a fire broke out in the Pier Fish Market, located halfway out on the pier and in December the Pier Cafe was completely destroyed by fire," according to the Oceanside Chamber of Commerce. The current pier was built in 1987.