Reasons That Systems Fail
Septic systems work because they ground absorbs water from the trenches. This water flows slowly through small channels and cracks between soil particles. Naturally occuring soil bacteria clean up the waste during this process.
Gradual Failure. As the system operates, bacteria in the septic tank digest most, but not all, of the solid matter. The undigested part sinks to the bottom of the tank in the form of sludge. If the sludge builds up too deep, it will plug up the pores in the trenches and keep them from absorbing water.
Intermediate failure. Each septic system has a maximum amount of water it can handle. If more water goes in than the system can absorb, either the system will quit working and back up into the house, or the water will find some other exit (usually to the surface of the ground). At first, this will only happen during rainy periods when the water table is high; later, the problem may become chronic. To avoid this type of failure, sources of excess water (sump pump lines, downspouts, pools drains, etc.) should not be connected to the septic system.
Raid failure. If the ground is heavily compressed, the channels in the soil close up and water can no longer percolate into the ground. This type of failure occurs when a massive structure (swimming pool, drivewat, patio, etc.) is built over the septic field, or when heavy vehicles are driven across the field.
If you are like most homeowners, you probably never give much thought to what happens when waste goes down your drain. But if you rely on a septic system to treat and dispose of your household wastewater, what you don't know can hurt you.
When septic systems fail, inadequately treated household wastewater is released into the environment. Any contact with untreated human waste can pose a significant risk to public health. Bacteria and viruses from human waste can cause dysentery, hepatitis, and typhoid fever. Untreated wastewater from failing septic systems can contaminate creeks, streams, lakes, nearby wells, groundwater, and drinking water sources. Read more at the Busseron Creek Watershed Website.