By CBS3 Staff

NORRISTOWN, Pa. (CBS) – A boil water advisory has been issued for portions of Montgomery County after a water main break. Pennsylvania American Water issued the advisory Monday for all customers in its Norristown water system.

That includes 33,500 customers in the boroughs of Norristown and Bridgeport and portions of West Norriton, East Norriton, Upper Merion, Plymouth, Lower Providence, Whitpain, Worcester, Whitemarsh and Perkiomen townships.

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Officials say there was a drop in positive water pressure due to the water main break on East Marshall and Markley Streets in Norristown. As a result there is an increased chance the water might contain disease-causing organisms.

Residents should not drink the water without boiling it first or use bottled water until further notice.

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Bring all water to a rolling boil, let it boil for one minute, and cool before using. You should use boil or bottled water for drinking, making ice, washing dishes, brushing teeth and food preparation.

Crews have isolated the main break, and water pressure is currently being restored to all customers.

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