Cesspools and septic systems are the two waste disposal options for homes that are not connected to public sewage treatment systems. Septic systems and cesspools are commonly found in rural areas. Septic systems come in a variety of shapes and sizes, and are generally considered to be an improvement over cesspools.
A septic system receives and treats wastewater from homes before releasing it back into the groundwater supply. Treatment of wastewater includes the removal and storage of inorganic solids, the processing of sewage and the biological removal of harmful bacteria and viruses. Most septic systems are comprised of a tank and a drainfield, although some types of systems--such as a multi-flow septic system--include only a tank. The important distinction is that a septic tank removes pollutants from wastewater.
A cesspool is any pit or container that receives wastewater from a house or building. The term "cesspool" is usually used to refer to an open pit that is lined with rocks or concrete, but an underground tank or holding container that is not connected to a drainfield can also be defined as a cesspool. The main function of cesspools is the storage of wastewater.
People who have cesspools probably have them because they are relatively inexpensive. Because they have more components and are much more complex, septic systems are considerably more expensive to install. The Rhode Island Department of Environmental Management estimates that the replacement of a cesspool with a typical working septic system has an average cost of $10,000 to $15,000. Another option may be the installation of a multi-flow septic tank, which does not require a drainfield.
If they are functioning properly, septic systems treat wastewater so that it is safe when it returns to the environment. Septic systems remove harmful bacteria and viruses that might otherwise contaminate groundwater supplies and sicken people. This function is extremely important, since the Environmental Protection Agency estimates that more than four billion gallons of wastewater is treated by the nation's septic systems every day. Cesspools do not treat wastewater. Wastewater that is pumped into cesspools is not safe, and it can easily spill over or seep into groundwater supplies and sicken animals and people.
Properly functioning septic tanks are endorsed by federal and state laws. Largely because they have been determined to be environmentally unsafe, cesspools are no longer legal in many states. Homeowners with cesspools should check with their state to ascertain whether or not their property is up to code. Homeowners with cesspools on their property may want to consider removing them, especially if they may be fined according to local or state laws.