Precautionary Boil Orders

Naperville’s Water/Wastewater Utility is committed to providing high-quality, safe drinking water to its customers. Recently, the utility reviewed its procedures related to water main break response and testing due to the Illinois Environmental Protection Agency’s (IEPA) increasingly more stringent interpretation of the regulations on the requirement surrounding precautionary boil orders.

During this review, and based on scenarios with other communities in the region, the City became aware of the IEPA’s evolving stance and stricter enforcement on this issue, and as such, will begin issuing precautionary boil orders in June 2019.

What does a precautionary boil order mean?

Precautionary boil orders are meant to inform customers that there has been an incident that caused the water system to become more susceptible to outside contaminants. As a precaution, the City is notifying the impacted area to take precautions and not use tap water for drinking, brushing your teeth, cooking, or washing fruits and vegetables. Customers should only use bottled water or tap water that has been boiled for five minutes for these activities.

Precautionary boil orders do NOT mean water has tested positive for contamination. It is NOT the same thing as a mandatory boil order. Instead, it is a precautionary measure meant to empower customers to make the best choices for themselves, their families or their business customers until proper testing can be completed. A mandatory boil order has not been issued in Naperville since 1998.

When and why are you issuing these?

A precautionary boil order is most commonly issued when Water/Wastewater Utility crews need to shut down a segment of water main due to an emergency water main break or other maintenance activity. IEPA rules and regulations call for the immediate issuance of a precautionary boil order for any emergency which results in water pressures falling below 20 pounds per square inch. When pressure falls below that amount, there is a possibility that organisms outside of the water pipe could infiltrate the water system and cause illness (e.g. fecal or E. coli bacteria) or technical/physical problems in the water system have significantly increased the possibility of bacterial contamination.

The precautionary boil order does not mean that the water has tested positive for microbiological contamination. It is simply a precautionary measure until proper testing can be completed. Notification is made by the Water/Wastewater Utility to those consumers affected. The precautionary boil order begins once water returns to impacted customers and samples have been sent to the utility’s lab for testing.

How will I be notified?

During the day, Water/Wastewater staff will go door-to-door to affected customers to issue the precautionary boil order notification. Customers will receive an orange envelope that informs them of the precautionary boil order and includes a letter and FAQ sheet with more information adhered to their front door. An additional and identical envelope will be left on the garage or other prominent location in case a home owner does not enter through their front door.

On rare occasions, a precautionary boil order may need to be issued overnight. Utility staff will do their best to avoid this from happening. In the precautionary scenario above, Water/Wastewater staff will not ring door bells in the late evening or overnight hours, but will simply affix the door envelope to the front door and garage for residents to see in the morning.

Should a MANDATORY boil order need to be issued, emergency notification methods would be implemented, including use of the City’s Naper Notify mass notification system. But for a precautionary boil order with no confirmed contamination, only the door envelopes would be affixed overnight.

How long does a precautionary boil order remain in effect?

Each boil order situation is different, making it impossible to predict how long the precautionary boil order will remain in effect. It will not be lifted until testing shows that the water meets public health standards. (As a reminder, a precautionary boil order does NOT mean contamination has been found.) However, in general, a routine precautionary boil order and verification testing window will take between 24 and 48 hours to complete. Once a precautionary boil order has been lifted, Water/Wastewater Utility staff will go door-to-door again and issue green door tags to notify residents and businesses that the water has tested safe and the precautionary boil order is now longer in effect.

Should a MANDATORY boil order need to be issued, emergency notification methods would be implemented, including use of the City’s Naper Notify mass notification system. A red door envelope would be used in this instance. A mandatory boil order has not been issued in Naperville since 1998.

Where do I go for information if I’m a business and need help assessing next steps during a precautionary boil order?

Please contact your county’s respective health department if you have any questions or concerns about proper procedures for your business in the event of a precautionary boil order.

Precautionary Boil Order FAQs

Additional Resources