What is Category 3 Water?

What Is Category 3 Water?

What You Should Know

Category 3 water defined

If you’re reading this blog, you’re most likely dealing with Category 3 water damage. What is Category 3 Water damage? Category 3 water is a classified as highly contaminated water that can pose a threat to life and health – whether that is for humans or pets. Often times referred to as “Black Water”, harmful bacteria, viruses, chemicals, pesticides, pollutants, and pathogens reside in the water.

Sources of Category 3 Water

There are a variety of sources that can lead to water being classified as Category 3:

  • Sewage Backups are an unfortunate but common occurrence that property owners experience. Collapsed main sewer lines, tree roots in sewer lines, clumped products that were flushed are the most frequent
  • Overflowing Rivers & Streams due to broken dams or heavy rains. Contaminants from outside (think pesticide, dirt, fertilizers, animal remains) can all end up inside your property. 
  • Storm Surges occur when a storm is the sole reason for the sea level to rise. Strong winds push water onto land above normal predicted levels. There are many variables that affect the severity of the storm surge. Similar to overflowing rivers & streams, storm surges collect many contaminants from outside and bring them inside.
  • Stagnant water can become category 3 even if the water was from a clean source. Mold can begin growing within 24-48 hours and that mold can spread throughout the standing water.
  • Contaminated property’s can come in many shapes and sizes. Pet urine & feces, “hoarder materials”, blood, and human remains can contaminant water in a home and spread the contaminants throughout the property. 
  • Ground Water can become category 3 quickly. Similar to storm surges, rivers, and streams, ground water can bring outdoor contaminants inside. Prevention measures can mean ensuring downspouts move the water away from the property and landscaping is sloped away from the foundation to help avoid water from entering.
  • Clogged Toilets that overflow with contaminated materials are classified as category 3 water due to the nature of the material being flushed. Upon overflowing, those materials move with the water, wherever it goes.


Category 3 water damage can occur on all levels of your property and it’s important to be safe when remedying the issue. We have posted about a DIY approach to solving water damage, but want to stress that personal protective equipment should be worn at all times and proper HEPA air filtration should be used when mitigating. If you don’t feel adequately prepared, call our trained teams for immediate help. Personal protective equipment can mean gloves, goggles, HEPA masks, waterproof clothing, and boots. Commercial grade drying equipment and air filtration can dry your property more efficiently, more quickly, and more thoroughly while removing the contaminants.

Post Category 3 Loss Demolition and Dry Out
Overflowing Toilet PPE Dry Out

(800) 478-0366

Immediate Help

Certified Restoration Specialists

Service Restoration is a IICRC Certified Firm with
Technicians Certified by the IICRC with a Triple Master Designation

On Reviews

Customer Reviews

Leave a Comment

Your email address will not be published. Required fields are marked *

Call Now

Review us!

Pick whatever is most convenient to you, we appreciate you sharing your experience!