Suspicious Device Found in UW Arboretum; Deemed Safe

  • Incident date: August 4, 2025, 9:30 am
  • Incident type: Information
  • Location/address: UW Arboretum, near Mills Street Entrance

On Monday, August 4, 2025, at approximately 9:30 a.m., a UWPD officer on routine patrol in the UW Arboretum was flagged down by a passerby who reported what they thought was a grenade sitting on a railing on the boardwalk near the Mills Street entrance.

The officer immediately went to the area to investigate and confirmed what the passerby reported. UWPD officers quickly cordoned off the area as a safety precaution and shut down nearby Arboretum Drive.

Our partners with the Dane County Sheriff’s Office Hazardous Devices Unit responded to assist. They were able to determine that the device was an empty training grenade and was not a threat. By 11:30 a.m., the Arboretum was reopened.

While it’s unclear why the device was left on the boardwalk, it’s likely that someone found it, didn’t know what to do with it, and left it for someone to dispose of. If you ever find a potentially dangerous device, please contact local law enforcement so it can be safely handled and appropriately discarded.