This information is preliminary and subject to change.
Updated 9/4/2024
On August 11, 2024, about 6:48 a.m., a natural gas explosion destroyed a single-family residence at 2300 Arthurs Woods Drive, Bel Air, Maryland. [1] Two people died, and three people were injured. Several nearby residences were damaged, and families were displaced. (See figure.) At the time of the explosion, it was daylight and clear, with calm winds; the temperature was 67°F with no precipitation.
Before the explosion, on the evening of August 10, 2024, the affected home experienced an electrical power outage. A Baltimore Gas and Electric (BGE) representative (electric service technician) responded to the scene and referred the repair to a contractor.
Two BGE electrical contractors were working to repair electrical service when the explosion occurred. The homeowner and one of the contractors were fatally injured; the second contractor escaped the explosion with minor injuries.
On the evening of August 10, 2024, BGE’s responding electric service technician reported an outside gas odor at the affected home to its electric dispatch operator. One neighbor reported smelling a strong gas odor about 0.2 miles from the affected home to BGE, which responded to the area (about 0.2 miles from the explosion) and did not find a leak. In an interview with National Transportation Safety Board (NTSB) investigators, another worker stated that he smelled gas in front of the home about 6:05 a.m., immediately before the explosion.
BGE provided natural gas and electrical service to the affected home, with a natural gas distribution system near the home consisting of a 1-1/4-inch diameter plastic main, installed in 2006, and a 1/2-inch diameter plastic service line, installed in 2007. The operating pressure of the gas system at the time of the explosion was about 89 pounds per square inch gauge (psig), below the maximum allowable operating pressure. [2]
Electrical service to the home was supplied by a set of three electrical cables, installed in a common trench together with the gas pipe. [3]
Before NTSB investigators arrived, BGE completed a pressure test. BGE also recovered damaged electrical service lines and the plastic service line with a hole on the bottom. After NTSB investigators arrived, BGE tested for and detected subsurface gas in the area surrounding the exploded home.
While on scene, NTSB investigators examined the site where the explosion occurred, reviewed BGE’s operational procedures, gathered documentation, conducted interviews, and recovered physical evidence for examination by the NTSB Materials Laboratory. NTSB investigators also examined the remaining gas and electrical facilities to the affected home after they were excavated. The electrical and gas service lines were found to be between 3 to 15 inches apart.
The NTSB’s investigation is ongoing. Future investigative activity will focus on BGE’s construction practices, its process for recording and responding to odor complaints, and its pipeline safety management system, as well as other causal factors.
Parties to this NTSB investigation include the Pipeline and Hazardous Materials Safety Administration, the Maryland Public Service Commission, Harford County Sheriff’s Office, the Office of the Maryland State Fire Marshal, the International Brotherhood of Electrical Workers Local 410, and BGE.
1. All times in this report are local times.
2. The maximum allowable operating pressure was 99 psig.
3. A common trench is an installation practice where several utilities are installed in a single trench.