INDIVIDUAL WASTEWATER TREATMENT SYSTEMS IN COLES COUNTY
A properly designed, installed and maintained individual sewage disposal system is a very efficient and cost
effective method of wastewater treatment. Whether you are installing an individual sewage treatment system for a new
home or replacing a failing existing system, you need to consider the soils, landscape features, natural drainage
patterns and boundaries of the lot. Not every type of individual sewage disposal system is best in every situation.
In addition, other factors such as initial (installation) cost, maintenance expense, sensitive environments, and
even esthetic values may be important to you. This is a short overview of the most common types of individual sewage
disposal systems, Conventional Septic System, Buried Sand Filter and Aerobic Treatment Units, installed in Coles
Conventional Septic System
The wastewater flows to a septic tank and then to a subsurface seepage field.
- Economical to install and maintain.
- No discharge of treated wastewater.
- Least visible system.
- Soils must be permeable without high ground water.
- Uses a large area.
- Limited landscape development in the system area.
- Extreme elevation difference can be limiting or restricting for this system.
Buried Sand Filter
The wastewater flows to a septic tank and then to a constructed deep bed of filter materials. The filtered
water is collected and discharged to a reduced size seepage field or chlorinated and discharged to the ground's
surface in a manner that does not pond or create nuisances on the property served. Discharging into road ditches
or adjoining property is prohibited.
- Economical to maintain.
- Uses less space than a subsurface seepage field.
- Kind to the environment by providing good quality treated effluent (treated wastewater.)
- More expensive to install.
- The treated wastewater discharges to the ground=s surface which may require a NPDES permit.
- Elevations can be limiting.
Aerobic Treatment Units
The wastewater flows to the aerobic treatment unit. This is an electrically operated unit that injects or
circulates oxygen to speed the treatment process of wastewater. The discharge then goes to a reduced sized seepage
field or is chlorinated and discharged to the ground=s surface in a manner that does not pond or create nuisance
condition on the property served. Discharging into road ditches or adjoining properties is prohibited.
- Requires less space than a subsurface seepage field.
- Will work in some areas, such as high ground water, where few other alternatives exist.
- Installation is quick.
- Maintenance costs are significant.
- Requires ongoing service and maintenance.
- The effluent (treated wastewater) discharges to the ground=s surface which may require a NPDES permit.
- Will have several small visible structures allowing access for maintenance.
There are other alternative type systems including:
- drip irrigation systems
- recirculating sand filters
- mound systems
- cluster systems
Contact the Coles County Health Department about these or any other systems in which you are interested.