Incident Type: 
Tuesday, May 9, 2023 - 5:54pm
Tuesday, May 9, 2023 - 5:58pm
900 South Gammon Road
Madison, WI

The Madison Fire Department Fire Investigation Team (MFD FIT) spent several weeks re-examining the scene where the explosion occurred, gathering witness statements, and conferring with outside agencies and private investigators to attempt to piece together what led to this incident. Investigators determined the area of origin for this explosion was the garage of 941 Gammon Road.

While two potential fuel sources (a propane tank and natural gas-fueled appliances) were found or known to be in the area of origin, MFD investigators could not safely excavate or access certain areas to fully examine the damages. Multiple hypotheseswere explored. Currently, the specific cause of the explosion remains undetermined.
One area of focus was a 20-pound propane cylinder attached to a grill. The cylinder was found with the valve turned on, and one of the burners on the grill was also found in the “on” position. The propane cylinder was determined to be empty upon investigators’ examination of it, indicating the possibility that the propane had off-gassed into the garage.
The ignition source of the explosion remains unknown. The MFD FIT; The Federal Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF); the State Division of Criminal Investigation (DCI); and Madison Police detectives maintain that no evidence of a crime was found on the scene.

Private insurance investigators for the property continue to examine other appliances that were in the garage as potential fuel or ignition sources.
--PIO Cynthia Schuster (7/20/23, 8:47am)


The MFD Fire Investigation Team, with assistance from ATF, DCI, and the State Fire Marshal's Office, spent the day clearing debris and examining the scene to attempt to determine what caused the explosion on Gammon Road.

The investigation is not complete; however, at this time, the leading hypothesis is that the explosion is traced to a propane source located within the garage. The explosion is not believed to have been an intentional act. Additional investigation is still underway and is anticipated to remain ongoing for some time.

The Madison Fire Department wishes to thank City of Madison Engineering for its assistance in clearing debris to allow investigators to safely enter the occupancy and examine the scene.

--PIO Cynthia Schuster (Wed., May 10, 5:24pm)


The investigation into the cause of this explosion is ongoing. The Madison Fire Department Fire Investigation Team (FIT) expects to be processing the scene throughout the day.

A neighboring 8-unit building also suffered damage Tuesday evening as a result of the explosion, and occupants from that building were also displaced. A total of at least 21 occupants were displaced from both buildings.

During the response, firefighters rescued three pets, none of which appeared to be injured. A fourth pet, a cat, had been missing but was located, unharmed, around 11:00 p.m.

Damage estimates are not available at this time.

NOTE: The building where the explosion occurred is an 8-unit complex. An earlier version of this release erroneously described it as a 6-unit building. The release has been updated to reflect the correct information.

Updates will be posted as new information becomes available.

--PIO Cynthia Schuster (Wed., May 10, 9:34am)

Posted 07/20/2023 - 8:47am

At 5:54 pm, multiple callers reported an explosion to a townhome on S. Gammon Road and Park Ridge Drive to Dane County Dispatch. Arriving crews confirmed an explosion had occurred with significant damage to the structure. One resident was transported to the hospital by Madison Fire; three others transported themselves.
Due to the extensive damage to the 8-unit townhome, the on-scene crew called for Madison Fire Department's Heavy Urban Rescue Team (HURT) to respond to assist with the search of the affected structure. The Heavy Urban Rescue Team shored up the collapsed structure and deployed listening devices to search for trapped victims. At approximately 10:30 pm, crews announced they had cleared the affected structure with no additional injuries reported. 
MFD's Heavy Urban Rescue Team, MPD, Water Utility, Building Inspection, City Engineering, Animal Control, and Red Cross responded to the scene to assist. MG&E also checked the neighborhood to ensure residents in nearby buildings were safe. In total, 19 crews assisted in stabilizing the incident.
Currently, this incident is under investigation, but at this time, the cause is unknown.
At the time of this press release, South Gammon was being cleaned and expected to be reopened to traffic shortly.

Posted 05/10/2023 - 12:24am

Amy Lampe, (608) 243-0180