Groundwater pollution problems are among the main reasons why composting toilets in residential homes have been promoted massively. Because of that, a lot of homeowners all over the country are considering to use composting toilets over the regular ones. There are two types of composting toilets that can be used at home: the large, bi-level containers and the single self-contained units. #1: Large, Bi-Level Containers These containers are larger compared to the second type. They are bi-level, watertight containers. Chutes are attached to connect the toilet receptacle to the composting unit that is usually located in the basement. These solid wastes decompose on an inclined floor. As the new wastes enter the upper end, the waste are being pushed back to the lower end. The liquid waste is also drained to the lowest part of the tank where it is collected or evaporated. Compared to the second type, these large containers can be used for a long period of time because it can hold large compost volume. The composting process is easier and more stable compared to the smaller units because of this. Among the other advantages are being able to cope better with peak loads and can easily withstand seasonal or intermittent use. With a larger volume, the completely composted vault can be emptied once a year or every other year. #2: Single, Self-Contained Units The second type of composting toilets is connected with toilet receptacle. It is smaller and compromises a single self-contained unit that is located in the bathroom, itself. Though this type of composting toilets is usually for vacation homes (intermittently used), they are also promoted for year-round residential use. These units are easier to install, more affordable, and can be retrofitted into existing dwellings. However, since they are smaller, frequent use can result in an incomplete decomposing process. You can imagine how often you need to empty the vault. Overuse of this toilet can cause liquid accumulation.