What is Category 1, Category 2, and Category 3 water?

Category 1 water comes from a sanitary source and poses no substantial risk from human contact. Typical examples are a burst supply pipe, an overflowing sink, or a leaking appliance supplied by clean water. It is the most common category in residential water damage.

Clean water can often be dried out of materials, which is good news for what can be saved. The catch is that Category 1 water can degrade into Category 2 or 3 if it sits, as it picks up contaminants from the surfaces and materials it touches.

Category 2 water contains significant contamination and could cause discomfort or illness if consumed or contacted. Examples include water from a dishwasher or washing machine overflow, water from a toilet bowl with urine but no feces, and water that has sat long enough to pick up contaminants.

Category 2 water requires more careful handling and more aggressive cleaning of affected surfaces. Some porous materials that could be saved from Category 1 water are removed instead.

Category 3 water is grossly contaminated and includes sewage backups, floodwater from outside, and water that has been standing long enough to support microbial growth. It can contain pathogens, chemicals, and debris, and no one should enter or touch it without proper protection.

Category 3 losses are handled with strict safety steps: occupants stay clear, the crew uses protective equipment, porous materials that cannot be sanitized are removed, and the affected area is cleaned and disinfected before drying and repair.

The category drives three things: safety, salvage, and documentation. It tells everyone what protective steps are needed, which materials can be dried versus removed, and how the loss is recorded for insurance. A technician determines the category at the initial assessment and rechecks it if the water has been sitting.

If you are not sure what category your water is, treat it as contaminated until a professional confirms otherwise.