1: Clean water
Clean water, although still damaging, is the least polluting and pure water that will enter your home. All water colors will do damage such as warping wood, high humidity causing flooring to warp, damage to furniture and belongings and will destroy drywall. Clean water however, is the least damaging, so at least you've got that if this is the case. You can enter the water (watch for electrical outlets and avoid getting shocked!) and is is usually safe to work in being clear of most bacteria and chemicals.
2: Gray water
Gray water generally has impurities and needs more treatment once the area is cleared of water and dried out. Gray water tends to originate from sump pump pits (sump pump isn't working), water coming through foundation cracks, etc.
3: Black water
Black water is the worst water damage to see in your basement. This is a very serious issue. the first thing you need to do in this event is to call your local sewer and drain expert, as this problem is mostly due to a sewer back up. Once the issue is taken care of and the water drained, you need a very experienced water damage expert. Do not hire some "waterproofing" guy, they will not have the right experience or equipment. Black water has bacteria and other pollutants and is not safe to enter - period. Black water, again, usually a sewer backup, can enter from floor drain, a bad ejector pump in your basement (overhead sewer systems), or sometimes even from a sump pump if your sewer line is connected to your drain tile (old homes). If you see "sewer flies" - tiny flies with jagged wings, you've definitely had a sewer back up. Debris of various sorts will be visible including feces, paper products and female products (which is disturbing if you have no females living in your home). This will usually means that your city main sewer has backed up into your home and is very dangerous. Call only a water damage restoration expert!
Prevention
When seeing the starting point of any types of water in your home, you should take action and have it inspected before it gets serious. Sings of pending problems include water spots on the walls and ceilings, water evidence around floor drains in basements, slow drains in your basement and water seepage from foundation cracks.
how can you prevent any of this?
- Home inspections done regularly are a good start. They're cheap (relatively to water damage) and can save you a lot of headaches.
- At any sign of water evidence, call a water damage specialist to inspect and address.
- Ensure your home insurance policy covers rain and sewer backups, this is usual for most good insurance policies.