Step 2: Identify the Source
When addressing water damage, it is essential to first determine the source. Professionals and homeowners commonly classify water incidents into three categories based on contamination risk and origin. Correctly identifying the category informs what immediate steps are safe to take and when to call in trained professionals.
Category I refers to clean, potable water. This includes water from overflowing sinks or bathtubs, broken water supply lines, or a failed fixture shut-off valve. Category I water is the least hazardous and poses minimal contamination risk. When the source is Category I, homeowners can often take immediate actions to stop the leak and begin drying and cleaning, provided it is safe to do so.
Category II is commonly called “gray” water. This is not safe to drink but is not heavily contaminated with sewage. Typical examples include dishwasher or washing machine discharge. Gray water often contains soap, food particles, and other contaminants that increase the risk of bacterial growth and odors. While limited cleanup may be possible for Category II events, proper drying and disinfection are important to prevent mold and lingering contamination.
Category III describes “black” water, which is heavily contaminated and can contain harmful bacteria, viruses, or chemical pollutants. Sources of Category III water include sewer backups, water that has flowed across exposed ground before entering a building, and water involved in chemical spills. Because of the high health risk, Category III incidents require professional remediation teams equipped with appropriate personal protective equipment and immunizations. Do not attempt to clean or dry black water without professional assistance.
After identifying the water category, move directly to the next step: stopping the source.
Step 3: Stop the Source
Once you know the category, take action to stop the flow of water when it is safe. For Category I and II leaks, locate and shut off the supply. Familiarize yourself with your home’s main shut-off valve and test it at least once a year to ensure it operates correctly. If the leak originates from an appliance or fixture that has a dedicated shut-off valve upstream, close that valve to isolate the problem rather than shutting off water to the entire building.
If you are dealing with continuous sewage discharge from a drain, this typically indicates a blockage in your sewer line or an issue with the municipal sewer system serving your neighborhood. In such cases, contact your city waste water or public works department immediately to report the problem so they can dispatch crews to prevent ongoing sewage flows and public health hazards.
After stopping the source, assess the situation and begin planning drying and prevention measures if the water is Category I or II. If the incident is Category III, wait for professional remediation teams to manage the cleanup and drying safely.
In Part III of this series, we will cover strategies for preventing the spread of water damage and setting up effective drying systems for minor water damage events.
Water Damage Series
1. Check for Danger
2. Identify the Source
3. Prevention & Drying