There are different types of check valves. The one type that you will want to make sure that it is working in excellent condition is a backwater valve. This type of valve is used for sanitary drainage systems. If you have ever had a sewage backup then you know exactly how important it is to make sure that this type of valve is functioning properly.
A backwater check valve protects lower located rooms against flooding caused by return flow of sewage waters. Backwater valve prevents rodents and rats to enter the sanitary and rainwater drainage system as well as the building interiors. Preventing a sewage blockage is something that is important to prevent. The smell is un godly as well as the clean up.