Private Sewage Disposal System Options
If you plan to build a new house, Macoupin County Public Health Department (MCPHD) highly recommends that you determine what type of private sewage disposal system (PSDS) would best suit your property and your family’s needs prior to construction of the house. It is important to plan ahead because backfill from the basement shouldn’t be placed in the area where you are proposing to place the septic system. There are several different types of PSDS that are commonly installed in Macoupin County.
1. Install a septic tank with laterals (subsurface discharge). This option is highly recommended IF there is the “right” soil type that is suitable to absorb wastewater liquids. The septic tank collects waste from toilets, sinks, showers, and laundry wastewater. The solids remain in the tank and the liquids flow out into the lateral field. Septic tanks are recommended to be pumped out every 3-5 years depending on the number of people in the home. The lateral field is a system of trenches with perforated pipe. The wastewater liquids flow out of the perforated pipe and are absorbed by the surrounding soils. The soil type is the determining factor if this system is the best option for your property. A soil investigation is necessary to determine the soil type. This method is preferred because the seasonal high water table is identified. A soil scientist or other qualified person should conduct a soil investigation. A percolation test (perc test) is also allowed, but not recommended.
2. A septic tank followed by a buried sand filter. Again, the septic tank collects all the waste from the house and needs to be pumped out regularly. The liquids flow out of the tank and into the sand filter that filters the liquid. Then it is comes in contact with chlorine tablets in the chlorine chamber and is discharged onto the surface of the ground or into a stream, river, lake or pond. The filter is designed to have different layers of gravel, sand and pea gravel along with a distribution and collection pipe system. The discharge flows out of the chlorine chamber and causes an area of the ground to be wet all year long. The point of discharge needs to be located in a way to prevent it from becoming a nuisance for the homeowner or for the neighbors. A sand filter system should be considered when the soils for a lateral system are not adequate. A sand filter works well on a property with some slope; it may be installed on a flat or level piece of property but a mechanical lift station must be installed to pump the discharge to the surface of the ground.
3. Class 1 aeration units are usually installed on properties with limited space or may be considered when repairing a failed system. Aeration units are specially designed septic tanks that have a motor which forces air to be introduced to the wastewater. There is a settling chamber, a mixing chamber (with the motor), and a filtering chamber. The liquid exits the tank and comes in contact with chlorine tablets and then is discharged onto the surface of the ground or stream, river, lake or pond. The manufacturer is required to service the motor and add chlorine to the system for the first 2 years after installation. After that time it becomes the responsibility of the homeowners to pay for a service contract or to maintain it themselves. The homeowner needs to keep in mind that the motor will require electricity and an alarm system and there will be a wet area on the property all year. Again, the point of discharge needs to be located in a way to prevent it from becoming a nuisance for the homeowner or for the neighbors.
These are some of the most commonly used PSDS in Macoupin County. There are other approved PSDS available and we would be willing to discuss various options with you.