The San Luis Obispo County Public Works Department confirmed Thursday that coliform bacteria, or E. coli, was detected in the Lopez Water Distribution System, which provides water to the Five Cities area.
On Wednesday, a boil water notice was issued to residents in Arroyo Grande, Grover Beach, Oceano, Pismo Beach, and Avila Beach, and other customers of the San Miguelito Water Company (Zone 3).
Public Works reported that routine water sampling found repeated positive samples of the bacteria.
“This is the first time we have found repeated levels of coliform bacteria in the Lopez distribution system that was above acceptable levels so this is unprecedented,” said Shelly Cone, SLO County Public Works representative.
She added that state officials will be on-site this week to help determine the cause of the contamination.
“If coliform or E. coli is detected, follow-up sampling is immediately conducted until no evidence of contamination remains,” Cone said.
County officials said Thursday that continued testing is "showing a downward trend of this contaminant."
The cities and community services districts under the boil water order are reportedly conducting their own water testing and officials said that the order could be lifted on a community-by-community basis.
WATCH: Public Works explains water testing procedures
E. coli symptoms
According to the Centers for Disease Control and Prevention (CDC), people at an increased risk for E. coli infection include kids under the age of 5, adults 65 and older, and people with weakened immune systems.
Symptoms of E. coli infection can include diarrhea, stomach cramps, vomiting, and a low fever.
Health officials say symptoms usually begin two to four days after drinking contaminated water. Most often, people will get better at home without medical treatment but, in some cases, illness can be severe.
The CDC advises contacting a doctor if you experience the following symptoms:
- Diarrhea or vomiting lasting more than two days
- Blood in the stool or urine
- Fever higher than 102 degrees
- Signs of dehydration
- Unexplained bruising or rash
- Feeling very tired or irritable
- Decreased awareness
WATCH: Public Health doctor explains when to seek medical treatment
Boil water tips
People in the affected areas are advised to use bottled water or boil their water following these instructions:
- Boil all water for one (1) minute (rolling boil).
- Let water cool before drinking.
- Use boiled or bottled water for drinking, brushing teeth, and food preparation until further notice.
- Boiling water kills bacteria and other organisms in the water.
See the tip sheet below for additional information on safe water use during a boil water order:
How to get notified
County officials say they will alert affected residents by Reverse 911 and AlertSLO when the boil water notice is lifted.
Click here to sign up for text message and email alerts through AlertSLO.
WATCH: Five Cities residents stock up on bottled water after boil water notice
