A broken 20-inch city water main put parts of south St. Louis under a precautionary boil-water advisory Sunday after low pressure rippled across several neighborhoods. The notice covers Lindenwood Park, Northampton and St. Louis Hills and will stay in place until tests confirm the system is safe. City crews moved to isolate the break and collect samples, and officials say lab results are expected in roughly 24 hours.
City: Broken main caused low pressure
According to the City of St. Louis Water Division, the advisory was issued after a broken 20-inch main led to low system pressure. The division says it "has not detected any contamination to the water supply" and that the notice is precautionary. The affected area is mapped as bounded by Jamieson Ave. on the west, Fyler Ave. on the north, Hampton Ave. on the east and Loughborough Ave. on the south.
What residents should do
Officials are telling residents in the advisory zone to boil tap water vigorously for three minutes before drinking it, using it for cooking or brushing teeth, and to discard any ice from automatic ice makers, remaking ice only with boiled water, as reported by KSDK. Businesses that prepare food are instructed to follow the city’s boil-order guidance until the advisory is lifted.
Not the first precautionary order
City officials characterize these precautionary advisories as a standard response when the system loses pressure. The approach mirrors a similar South City advisory in June 2025, which was lifted after tests found no contamination. Current guidance stresses that low pressure, rather than detected contamination, typically triggers these temporary measures while samples are analyzed.
Where to get updates
Residents with questions can call Water Division customer service at 314-771-2255 or report taste and quality concerns to 314-592-8222. Updates and an FAQ are available on the division’s advisory page at stlwater.com. The advisory will remain in effect until tests confirm the water is safe to use without boiling, and officials encourage residents to sign up for NotifySTL alerts for real-time messages about the situation.
