The sand filter media needs to be a minimum of how many inches thick?

For sand filter media used in the context of private sewage systems, a minimum thickness of 24 inches is required. This thickness is critical because it provides sufficient depth for effective filtration and treatment of wastewater. A thick layer of sand allows for more efficient removal of contaminants as the wastewater percolates through, ensuring that harmful pathogens and solids are effectively filtered out before the effluent reaches any subsurface groundwater or drainage systems.

The 24-inch thickness also helps to maintain the balance of aerobic and anaerobic processes within the filter media, enhancing the breakdown of organic materials. In addition, adequate thickness minimizes the potential for clogging, ensuring longevity and optimal performance of the filter system. Understanding these requirements is essential for effective design and operation of private sewage disposal systems in Illinois.