An 8-inch water main near Graphic Packaging ruptured before dawn on Aug. 19, causing rapid reservoir drawdown and prompting the City of Pacific to issue a townwide precautionary boil advisory.

Public Works Commissioner Bergman told the Board of Aldermen the failure was detected by the city SCADA monitoring system at about 3:10 a.m. and “we lost approximately 665,000 gallons of water total.” He said Blackburn Reservoir briefly read zero on the telemetry (he said full is seven feet) and Oak Ridge Summit Reservoir fell to roughly 24 feet (full about 39.5 feet). Bergman said crews isolated the leak by about 5:30 a.m. and restored service to the affected large customer, Graphic Packaging, by 2:30 p.m.

The city issued the precautionary boil advisory because pressure in parts of town dropped below 20 psi, a threshold that triggers Missouri Department of Natural Resources guidance, Bergman said: “DNR mandates a precautionary boil advisory for any affected areas of the pressure drops under 20 PSI and for water samples to be taken before lifting it.” He added that the bacteriological samples require a 24-hour incubation and that he expected results “by about 3:45 p.m. tomorrow.”

Bergman described the physical damage: “About half, right at half of the 8-inch main for about 4 feet…literally half of the 8-inch main was completely blown off of the ductile line,” and he estimated flow during the break at roughly 77,400 gallons per minute. He told the board he had isolated the leak, cut out the broken section and installed a replacement section. Staff plan to investigate replacement of the larger stretch of 8-inch line in the near future.

Mayor Filley and members of the board thanked water and public-works crews for their overnight work. Chief Klingler and staff assisted with notifications and public-safety coordination; Bergman said he used the city’s Regroup alert system, the city website and social channels to notify residents and asked residents who have not already done so to sign up for Regroup.

The advisory covered the entire town because officials said it would be difficult to determine precisely which low-pressure pockets had been affected and to notify only those households. Bergman said the advisory is “precautionary” under DNR rules, distinguishing it from a DNR-issued boil order that would follow confirmed positive samples.

City staff said they flushed the repaired main, submitted bacteriological samples to the lab and would lift the advisory once samples are clear and pressure is restored.

Residents with questions were told to consult the city website, sign up for Regroup alerts or call city hall for assistance.