Functional testing of septic system as part of a real estate transaction. Additional fee involved.
Types of Septic Systems
The two main types of systems seen in this area are conventional and aerobic. The main difference in the two systems is where the main treatment of the dirty water (effluent) occurs.
An aerobic system will usually have 3 to 4 or more chambers with an additional pump (aerator) adding oxygen to the water to aid in treatment. It will also have a port to be able to add either a liquid or tablet chlorine to the tank. The system will also have a pump and sprinkler heads in the yard where the treatment finishes. Occasional inspection and maintenance is required.
A conventional (or anaerobic) system has two to three larger tanks. It will also have a leach field somewhere in the yard (usually unseen until there is an issue). It can either be gravity fed or a low pressure dosing (LPD) system. In a gravity fed system, the effluent leaves the tank when it reaches a certain level and feeds out into the leach field. In a LPD system, a pump is actuated when the water gets to a certain level and it is pumped out under pressure into the field.
The inspection of system includes functionally testing the system to actuate the pumps, testing of warning systems and visual inspection of system. A reading of the depth of both the scum and sludge levels, when accessible, should also be part of the inspection.
In Comal county, the original permit can be a helpful way of locating information about the homes system.
Inspection does not include the digging out of the tank lids or pumping.
Pumping is recommended every 3 to 5 years or sooner based on usage.