Septic systems, also called on-lot systems, are really sewage systems that treat and dispose of domestic sewage through natural processes. Liquid wastes from a treatment tank percolate through soils where it then becomes neutralized and further broken down. In contrast to a centralized system which collects and treats sewage from multiple homes and disposes of the sewage off-site, septic system operation and maintenance remains the responsibility of the homeowner.
These on-lot systems have, in the past, been labeled as interim which often gave the illusion that eventually they would be replaced with public sewers. While in operation on-lot systems require specific operation and maintenance requirements which if not met, the system will either fail completely or function well below its capabilities. In either case, public health hazards or pollution problems will be the result. When public health hazards or pollution problems occur, the municipal government is legally responsible to find solutions.
Pennsylvania Sewage Facilities regulations, under Act 537, includes provisions for establishing legal, administrative and financial mechanisms for long term operation and maintenance of municipal sewage including on-lot sewage disposal systems or privately owned treatment facilities.
Today, many present and proposed Township ordinances provide for the regulation, inspection, maintenance and rehabilitation of on-lot sewage disposal systems and establish penalties and appeal procedures necessary for the proper administration of a sewage management program. Most Sewer Management Programs currently operating in Pennsylvania require the regular pumping of on-lot treatment tanks once every three years. or whenever an inspection program reveals that the treatment tank is filled with solids or scum in excess of 1/3 of the liquid depth of the tank. Requirements may also include holding tank maintenance and disposal.