Boil Advisories and Boil Orders

What is a boil advisory?

A Boil Advisory is issued by Columbia Water & Light when there is a water main break that causes the pressure to drop. A pressure drop could cause a back flow situation where a contaminant could be siphoned into the water distribution system. A Boil Advisory requires water customers boil their water in case the water is contaminated. The water quality tests take 24 hours to process so Boil Advisories usually last for one day.

What is a boil order?

A Boil Order is issued by the Missouri Department of Natural Resources when there are known problems with the water supply. This requires water customers to boil their water for safety purposes. A Boil Order will last a minimum of two days to allow for water testing results to confirm the water is safe to drink.

What should I do during a boil advisory/order?

A Boil Advisory is a precautionary measure. A Boil Order is for when there is known contamination. When either is called, customers are urged to take the following precautions:

  • Boil water for three minutes prior to using it for cooking or drinking.
  • Do not consume ice from an automatic ice maker. Remake ice with water that has been boiled for three minutes.
  • Wash dishes and food contact surfaces by immersing for one minute in clean tap water that contains one teaspoon of unscented bleach per gallon of water.

How will I be notified?

When Columbia Water & Light issues a Boil Advisory, staff will notify the customers directly affected or served by the water main that has been repaired. 

If it is a planned or minor water main repair, Water & Light will use door hangers for notification.

Phone calls will be made (as listed in the chart below) to the phone number listed on the Utility customer’s account.  Please make sure you have the correct phone number on file. You can update your contact information by clicking here.

If the boil advisory is widespread, Columbia Water & Light will utilize local media to inform the public.

Columbia Water & Light uses Rave Mobile Safety Alerts for direct notification to customers who sign up for the service. Customers can choose to receive alerts via text message, email and/or phone call.

What Is the notification procedure?

Customers Affected Notifications Time of Notification(s)
BOIL ADVISORY
Fewer than 50
  • Door Hang Tag
  • Rave Alert
  • 24 hours/day
  • 24 hours/day
50 to 200
  • Door Hang Tag
  • Rave Alert
  • Phone Call
  • 24 hours/day
  • 24 hours/day
  • 6 a.m. to 10 p.m.
More than 200
  • Rave Alert
  • Phone Call
  • Press/Media
  • 24 hours/day
  • 6 a.m. to 10 p.m.
  • 24 hours/day
BOIL ORDER
Any number
  • Rave Alert
  • Press/Media
  • 24 hours/day
  • 24 hours/day

What causes water main breaks?

Columbia Water & Light maintains approximately 3.5 million feet of water distribution lines ranging from 1.5 inches to 36 inches in diameter. The utility has an on-going maintenance plan and strives to provide reliable water service. There are factors that can affect the system that are beyond the utility’s control. For example, Columbia’s soil has a high clay content which can shift when there is high moisture content and/or drastic temperature changes. This shifting can lead to the pipes in the ground moving which can cause breaks.

How often do water main breaks usually occur?

The amount of water main breaks for the system has been less than two per week for the last 10 years. The average number of affected customers for each break is less than 20. During times of drought, high moisture or large changes in the temperature, the soil can shift more which causes more water main breaks.

What are the state regulations for boil advisories?

One of the Missouri Department of Natural Resources recommendations from the 2010 Compliance and Operation Inspection states, “Anytime the pressure in the distribution system drops below 20 psi, the system must notify affected customers, issue a boil water advisory until further notification for the affected area and send our office a low pressure report within 48 hours of discovery.” To comply with the recommendations, a Boil Advisory will be issued to all affected customers for every main break where the system pressure drops below 20 psi.

Water Division contact information

After hours water or electric emergencies: 573.875.2555

Water Administration Office, Monday – Friday, 8 a.m. to 4:30 p.m.

Contact Center: 573.874.2489

E-mail: Wlmail@CoMo.gov

NOTE: e-mails are not usually answered after hours or on the weekends