A grenade-type improvised explosive device was discovered and detonated in an Alabama reservoir that serves as the sole drinking water source for roughly 350,000 people, officials said Thursday.
Divers surveying the Converse Reservoir Dam for routine maintenance discovered the bomb, which the Mobile Area Water and Sewer System (MAWSS) described as a "grenade-type IED," and immediately alerted the Mobile County Sheriff’s Office (MCSO), according to authorities.
The device was secured and detonated by a multi-agency team of operators including personnel from the FBI Bomb Squad, Mobile Police Department Explosive Ordnance Detail, Alabama Law Enforcement Agency's Bomb Squad, MCSO and the Daphne Search and Rescue Team, according to MAWSS.
MAWSS Director Bud McCrory called the IED discovery "an unprecedented threat" to the area's drinking water, adding "we are fortunate that this device was discovered before it could cause serious damage to our water supply or harm to individuals."
The Converse Reservoir is the sole source of drinking water for the Mobile area's 350,000 residents, law enforcement partners – as well as the quick thinking of our contractors and divers – in identifying this device and safely destroying it," McCrory said.
MAWSS said it is working with law enforcement agencies to investigate how the bomb got in the reservoir and how long it had been there. The agency will also work with law enforcement to increase security around the dam.
The Converse Reservoir and its dam are federally designated critical infrastructure. The dam is classified as a high hazard potential, Federal Emergency Management Agency (FEMA).
Fox News Digital contacted MAWSS, MCSO and the FBI for additional comment.