Richard Sepolio, 24, faces a host of charges including four counts of vehicular manslaughter while intoxicated and three counts of causing gross bodily injury in a DUI crash.
He was headed north on Interstate 5 when he lost control of his GMC pickup while transitioning onto the bridge about 3:45 p.m. He smashed through a concrete retaining wall and plunged into the park, where hundreds were gathers for the La Raza Run motorcycle rally.
Two couples, Andre Banks and Francine Jimenez from Hacienda Heights, Calif., and Cruz and AnnaMarie Contreras from Chandler, Ariz., died in the crash. Nine others were injured, three seriously.
Sepolio, an aviation electrician, was arrested afterward on suspicion of causing injury or death while driving drunk. He remains hospitalized with major injuries.
Blanca Sepolio, the man's mother, said family members didn't wish to comment on the crash when reached Monday.
A military spokesman said it is too soon to say what next steps the Navy will take.
"The Navy is supporting the investigation as they can, and we can't speculate from there," said spokesman Brian O'Rourke.
Sepolio enlisted in the Navy in September 2014. He went to boot camp at the Recruit Training Command Great Lakes in Illinois and attended apprenticeship schools in Pensacola, Fla., and Norfolk, Va.
He was stationed in San Diego in September 2015 as an aviation electronics technician, or a J130, and was assigned to Helicopter Combat Squadron 6. Aviation electronics technicians troubleshoot and repair a number of electronics in Navy aircraft.
When he was 19 years old, Sepolio was arrested in Texas on suspicion of possessing or delivering drug paraphernalia. He was jailed on $600 bail. It's unclear how the case was resolved.
On Monday, several community members tended to a growing memorial of candles and flowers in Chicano Park, where the crash occurred.
Family members mourned the loss of AnneMarie and Cruz Contreras, who were married for 35 years and described as "two beautiful souls" in sentiments posted to a GoFundMe page.
AnneMarie was a teacher's assistant at Jane Dee Hull Elementary school in Chandler, and Cruz spent the last decade mentoring teens in the couple's community. They spent their free time cruising on their motorcycle.
"Together, they spent many years providing a loving home for many of Arizona's foster children," nephew Jacob Contreras said on the page.
Andre Banks, who was a biker, had gone to Chicano Park to enjoy the festival, said long-time friend David Sloane of Sacramento. Banks was a member of the Life Support Alliance, a group of former life-term prisoners who have been granted parole.
Banks was paroled about seven years ago after more than two decades behind bars. He turned his life around while serving time, Sloane said.
Saturday's incident marked the fifth time a vehicle has plummeted off the iconic San Diego-Coronado Bridge since 1980, when a car plunged into the bay after a crash with another vehicle. The three sailors inside died.
More than a decade later, on Nov. 16, 1992, William Wylie Jr., 27, a Navy enlisted man being pursued by police was fatally injured when he lost control of his sporty Mazda and plunged 150-foot from the bridge into Chicano Park.
On Christmas morning in 2003, a 19-year-old sailor struck a concrete barrier with her car and fell 50 feet from the bridge. The car caught fire near Chicano Park. She survived the crash.
Less than a month later, on January 13, 2004, a tour bus making a lane change on the bridge hit a pickup and knocked it over the bridge railing. The vehicle landed more than 140 feet below, near Harbor Drive and Cesar E. Chavez Parkway, killing the driver, Orlando Casinio, 49, of San Marcos.
Caltrans officials said in a statement Monday that the bridge was inspected and was found to be structurally sound. Spokeswoman Cathryn Bruce-Johnson said the results of the California Highway Patrol's investigation into the crash will help the organization determine whether any further action should be taken.