There are three different types of water:
Clean Water – This is harmless to people and typically comes from leaky pipes or water heaters or overflowing bathtubs or drains.
Gray Water – This is contaminated water that can cause sickness. It was clean but became contaminated by traveling through your home. For example, an upstairs leak may become contaminated as it travels down through the drywall and insulation.
Black Water – Sources of this are ground surface water and sewage. It is highly unsanitary and can cause harm to people.