Aerobic Sewage Systems -- What are they, and how do you take care of one?
If you are new to country living, and just moved into a house that has an aerobic system for sewage, relax. Aerobic systems are very reliable and with minimum care will give you years of trouble-free service. In many rural areas in Texas, aerobic sewage systems are now the preferred method for residential waste disposal. Traditional septic systems require long "leach lines" which require porous soil, and digging up large portions of the area around each home to install the drainage pipe. Aerobic systems are much more efficient, do not require leach lines, and can actually be used as part of a landscape plan since the "gray water" released by the system is safe for watering your plants.
Aerobic systems are basically individual sewage treatment units, and work in a manner similar to the treatment plants of the public utilities. There are two working areas inside the aerobic treatment plant. The first is an aeration zone where air is introduced, agitating and adding oxygen to the liquid waste. This promotes the growth of bacteria, which in turn digests the organic matter in the liquid. The second area is the "quiet" zone, where the liquid rises upward. As the water rises upward, the suspended solids settle back into the aeration zone. The process continues until the final discharge of a clear odorless liquid is released thorough sprinkler heads. In the most modern systems, homeowners can determine if they want the sprinklers to go off "on-demand" -- that is, whenever the holding tank is full enough to discharge the liquid, or on-timers, sprinkling at designated times during the day.
All aerobic systems must be installed by licensed companies, and must pass inspection by a licensed inspector. The county of Denton records all installations of aerobic systems, and requires the homeowner to keep the system on a regular maintenance contract with a licensed company. Aerobic systems are very low maintenance. There are no moving parts inside the treatment plant. Chlorine tablets must be added periodically, and the homeowners can test the liquid and add chlorine tablets themselves, or have the regular maintenance company handle the chlorine tablets. Periodically, the maintenance company will clean the screen around the pump arm in the tank if the system is designed with one internally, and will clean the filter at the pump motor if the selected system has an external filter. All systems have some type of alarm to notify the homeowner if the water in the "quiet" zone is too high and not getting discharged properly. The alarm may be audio only, or both audio and visual. Periodically, every 1-3 years depending on usage, the main tank is pumped out. This task is easier than with a traditional septic system. A large hose is put into the tank through the top, after the lid is removed, and the contents are pumped into a disposal truck. There is no digging required.
