Types of Flood Water: Greywater and Black Waste

Brad LackeyWater Damage, Water Damage Prevention

One of the worst things a homeowner can find in their home is a couple of feet of water.  Water damage is the most common type of property damage that homeowners experience and indoor flooding in particular can cause very extensive structural damage and lead to the presence of mold and mildew.

When people discover flooding in their home, it is natural to feel frustrated and immediately focus on removing the water.  It is also important to consider that the flood water in your home could be contaminated and a danger to your health.

Flood Water is a Serious Problem That Needs to be Handled as Soon as Possible

Not all flood water is the same. Standing water in your home could be contaminated depending on how it got there in the first place. The most common causes of home flooding are natural floods, rain seepage, broken appliances, pipe bursts, and sewage backups.

In each one of these scenarios, the water comes from a different source and is therefore subject to different levels and types of contaminants. Contaminated flood water is generally categorized as greywater or black water which is differentiated by the types of contaminants it contains.

It is important for homeowners to understand the different types of flood water as well as how to recognize when the flooding in your home may be contaminated.

Flood Water Categories

The water inside a home or building is categorized as one of three types; clean water, greywater, or black water.  The following descriptions will help you recognize which type of flood water you may be dealing with.

Clean Water

Water is considered clean water if it is clean and safe enough to drink. Clean water includes tap water, water from appliances and plumbing fixtures, and rain water or snow melt.

If there is a leak from your refrigerator, a busted pipe, or washing machine, then the water is clean, at least initially.

Clean water can quickly become contaminated when it comes into contact with objects and surfaces that may contain chemicals or other substances that can turn it into greywater.  A clean water leak or flood may become contaminated within 48 hours.


Greywater, also known as sullage, is water that contains a level of harmful contaminants such as chemicals and other pathogens. This type of water does not contain fecal matter or sewage, but the contaminants it does contain can be harmful to your health.

The most common sources of greywater include showers, sinks, dishwashers, and washing machines and the water for each may include different types of contaminants.

Water from sinks, bathtubs, showers, and washing machines may contain excreta which is a type of human waste that can be treated.  Water from kitchen sinks and dishwashers are likely to contain fats and grease.

Greywater causes more damage than clean water because of the contaminants it contains, and it can turn into black water within 48 hours.  Greywater can also cross the line into black water if it is mixed with sewage or more harmful human waste.

Black water

Black water is the most hazardous type of water.  The most common types of black water in the home are wastewater from the toilet and sewage that contain human waste such as feces and urine.

Water from natural floods is also considered black water because it may contain sewage and other harmful pathogens like bacteria and viruses.

The possible health effects of black water are quite severe as exposure can lead to serious illnesses including Norovirus, hepatitis, and cholera.  If you suspect that the water in your property is black water, you must avoid any contact with the water and immediately call our water damage restoration professionals.

Black water is very dangerous because the contaminants that threaten your health can also make the damage worse.  Once the water is removed, the contaminants may still remain in the air and on the affected materials.

This is why it is important to contact a trusted water damage restoration professional who can effectively clean and sanitize the area and reduce the risk of negative health effects.

Responding to Black Water and Greywater

If there is black water or greywater in your home, you should not waste any time calling a professional to have it cleaned up. The damage caused by the water will only get worse and the risk of experiencing negative health effects will increase.

Call ServiceMaster by Restoration Contractors now at (260) 420-1502

The harmful pathogens within the contaminated water thrive in moist environments and they feed on organic materials the include cellulose like wood and drywall.  Make sure you take the following steps to protect your health and clean up the damage from black water or greywater:

  • Contact ServiceMaster by Restoration Contractors immediately to start the water extraction and removal process. If the flooding was started by a broken pipe or plumbing fixture, then you also need to call a professional plumber to repair the damage.
  • Try your best to avoid any contact with the water, especially if you do not have the proper personal protective equipment (PPE). Our restoration professionals have the PPE needed to safely deal with the water.
  • Do not use the water system in your home, including the toilets, until the problem is located and repaired.
  • Plug all drain openings to avoid additional backup.
  • Do not run your heating or air conditioning and cover your vents so the water does not get into your HVAC system.
  • Turn off the power in your home if you can safely reach the circuit breakers.
  • Do not try to clean up any of the mess yourself because you will be putting yourself at risk for negative health effects.

It may be difficult to tell if the water in your home is greywater or black water, especially if you cannot tell the source of the flooding.  A good rule of thumb is to avoid contact with the water if you suspect that it may be contaminated or if you aren’t sure.

Our water damage restoration professionals at ServiceMaster by Restoration Contractors are prepared to deal with greywater and black water in homes and businesses.

We use advanced equipment to safely remove the water and we can properly clean and sanitize the affected areas so that they are safe to use afterwards.  You can contact us anytime to deal with flooding emergencies in Fort Wayne, IN and the surrounding areas.