OSSF is a common construction acronym which stands for on-site sewage facility and refers to an array of waste water treatment devices where waste is treated and disposed on the same property.

The most common example of on-site treatment is a septic system which is used in a quarter of American homes, businesses and other facilities. Septic systems were developed in the late 1800s but were still a new concept for rural communities and businesses not connected to big sewer grids. Up until the 1950s and 1960s, cesspools were still common despite the dangers they posed to groundwater supplies.

The EPA estimates that contaminated groundwater from poor waste water management leads to approximately 200,000 viral and bacterial illnesses each year. As a result of problems with traditional disposal methods, advanced on site sewage facilities have been developed to eliminate waste while reducing the likelihood of having it enter drinking supply.

Septic systems aim to contain and dispose of wastewater in a manner that is more environmentally friendly than older methods. The system will collect waste and then slowly remove it through anaerobic digestion, drainage and percolation.

Waste will often drain into what is a known as a “drain field” where a system of perforated pipes and porous material will distribute it through an area. Depending on the volume, this distribution can be scheduled and certain areas of the field may be rotated with effluent sent to other areas. These systems can also be combined with bio-filters, living materials which take additional waste and process it.