Residents on the Sussex Corner municipal water system are being told to boil their water before consuming it.

A boil water advisory was issued Friday after routine testing showed the presence of coliforms in the system.

“These tests have indicated the water system integrity has resulted in potential contamination of drinking water, and, as such it is necessary to undertake this advisory as a precaution,” said a letter distributed to customers.

All water destined for drinking, preparing infant formulas and juices, making ice, washing fruits and vegetables, cooking, or dental hygiene should be held at a rolling boil for one minute.

Adults, adolescents and older children may shower, bathe or wash using tap water but should avoid swallowing water.

Infants and toddlers should be sponge bathed to reduce the chance of them swallowing the water.

Officials said it is still safe to use tap water for washing your hands, doing laundry and washing dishes.