Initiating an Advisory

Drinking water advisories are issued for reasons identified in federal or state regulations or by decisions made by the water system. The situation and characteristics of the contaminant(s) of concern determine what type of advisory to distribute:

Essential Information

  • Who you are
  • What action customers should take
  • What event occurred and a description of the problem
  • Where it occurred
  • When it occurred
  • Expected duration
  • Why it happened
  • Who is affected
  • Basic information about the water system
  • Current actions being taken
  • Requested agency responses
  • What public notice is required when appropriate
  • Where to get more information
  • Informational
  • Boil Water
  • Do Not Drink
  • Do Not Use

Use the Essential Information list to collect data and develop communication materials.

Each state that has primacy specifies particular mechanisms for state notification. Be familiar with your water system’s protocols for notifying your primacy agency. See Appendix C: Online Resources, Primacy Agency.small key representing resources


A key component of a drinking water advisory is to communicate clearly the area affected. Many customers do not know which water system provides their service and broadcast media usually reach a large audience beyond the affected area.

Clearly describe the boundaries of the affected area using street names, place names, building identification information (e.g., building numbers, unit numbers, wings, etc.) and well known reference points.


Maps help illustrate the affected area. Water systems can generate maps using internal or online mapping tools (e.g., geographic information system [GIS]). These maps can be posted on agency websites, or distributed electronically or as printed material. Update the map as the situation changes.

Figure 5: Example of a Simple Map to Designate an Area Affected by a Drinking Water Advisory

a simple map to designate an area affected by a drinking water advisory

Activate your internal communication SOP. Use information collected to brief staff. Depending on the situation, also brief your partners:

  • Wholesale, consecutive, and neighboring water systems
  • Public health department
  • Critical customers (see Critical Customer Checklist Cdc-word[DOCX – 1 page]small wrench icon representing tools to assist in identifying at-risk populations served by a water system)
  • Public officials
  • Emergency management
  • Community organizations
  • Businesses, childcare facilities, correctional facilities, food service, healthcare providers and facilities, and schools

Provide the Call Center Data Checklist Cdc-word[DOCX – 1 page]small wrench icon representing tools to call center or customer service staff and partners.