At 9:12 A.M., an explosion occurred in the hold. In an instant, all 27 volunteer firefighters were killed. Some of their bodies were disintegrated by the heat and pressure of the explosion. All that remained of their apparatus were piles of twisted metal. Texas City lost all but one of its firefighters and every piece of its apparatus in the explosion. Until the 9/11 terrorist attacks in New York City, this was the largest single loss-of-life incident experienced by any fire department in the United States.
In addition to the loss of life, there was extensive property damage. The force of the explosion - heard over 150 miles away - knocked two small airplanes out of the sky. Debris fell on homes and businesses, setting many buildings on fire. People on the streets of Galveston, 11 miles away, were knocked to the ground by the force of the blast. Chemical plants and petroleum storage facilities along the bay were set afire as well. The explosion set fire to the High Flyer, docked near the Grandcamp and also loaded with ammonium nitrate. An anchor from the Grandcamp that weighed over 3,000 pounds was propelled two miles away and created a 10-foot-deep crater. A seismologist in Denver, CO, recorded the shock waves from the explosion and thought an atomic bomb had been detonated in Texas. In Omaha, NE, the Strategic Air Command briefly elevated the United States defense condition (Defcon) believing a nuclear attack was taking place.
Following the explosion, firefighters responded to Texas City from communities across southern Texas, some from as far as 60 miles away. A lone Texas City firefighter, Fred Dowdy, who had not responded to the initial call, coordinated the mutual aid firefighters arriving in Texas City to offer assistance. Dowdy's late response likely saved his life, as he was the only member of the Texas City Fire Department who was not killed by the explosion. Eventually, more than 200 firefighters responded from as far away as Los Angeles, CA.
At approximately 1:10 A.M. the following day, the High Flyer exploded. By many accounts, the High Flyer explosion was greater than the one that occurred in the Grandcamp, but the dock area had been cleared and casualties were light in the second explosion. Additional property damage occurred from the force of the blast and more fires were set throughout Texas City. A small tidal wave created in the bay traveled over 150 feet inland.
It took almost a week to control and extinguish all of the fires caused by the two explosions, which destroyed the Grandcamp and High Flyer. The last body was removed from the debris nearly a month later. The Grandcamp and High Flyer explosions resulted in the worst industrial accident, producing the largest number of casualties, in the history of the United States.
When it was all over, more than 405 identified people were dead and more than 3,500 injured. There were also 63 people who died and could not be identified and more than 100 others were presumed dead, as their bodies were never found. Some believed that hundreds more were killed, but unaccounted for, including visiting seamen, non-census laborers and their families, and untold numbers of travelers - although some people who were as close as 70 feet from the Grandcamp when it exploded survived. Refinery infrastructure and pipelines, including about 50 oil storage tanks, were extensively damaged or destroyed from the blast pressure and resulting fires, which burned for days. A Monsanto chemical plant was heavily damaged and 143 of the civilian deaths occurred there among employees. Over 500 homes were destroyed and hundreds of others damaged, leaving over 2,000 people homeless. Property loss was listed at over $100 million. Bulk cargo-handling operations never resumed at the Port of Texas City. However, the Monsanto plant was rebuilt and back in operation within a year. The cause of the fire has never been officially determined, but it could have been caused by spontaneous combustion or, a carelessly discarded cigarette, or intentionally set.
Services for the dead who could not be unidentified were held on Sunday morning, June 22, 1947. Nineteen volunteer firefighters were listed as missing and some may have been among the unidentified buried on that morning. Even though there was little advance notice of the funerals, cars were parked 1Â½ miles on both sides of the highway leading to the cemetery. The crowd was estimated at 5,000. Sixty-three caskets were transported from Camp Wallace by separate hearses from 51 funeral homes representing 28 cities. It must have been a striking procession, likely one of the longest to have ever occurred in the United States. The caskets were carried by volunteer pallbearers provided by the American Legion, Veterans of Foreign Wars, labor organizations and volunteer firefighters. Each casket was decorated with flowers donated by the florist's association.