ST. LOUIS — A portion of St. Louis County is under a cautionary boil advisory after a 20-inch water main break. Missouri American Water says about 3,600 customers are affected.

Missouri American water says this is just a precautionary measure.

“Water is okay to use without boiling for non-consumable use such as washing clothes and bathing. Customers will be notified when the advisory is lifted which should be approximately 48 hours from now,” statement from Missouri American Water.

The water main break has closed a portion of Gravois Road near Musick Road. Repairs are expected to take 10 to 12 hours. It is expected to be lifted Sunday night.

The precautionary boil, order is for the following area: 

Watson Road from Cheshire to south Laclede Station Road, Heede Road to south on McKenzie to Dorisann Court over to Tesson Ferry Road and south to Puttington Drive and up to Grant Road.

map of the area: