A dye test is a relatively low cost, non-invasive method for testing of private sewage treatment systems. It is a limited, performance-based test. This test does not provide a guarantee of the present, or future, performance of the system. It is not a full evaluation of a sewage treatment system, but nonetheless provides valuable information regarding the present performance of the system. A septic dye test is ideally suited for evaluation of septic systems for real estate sales purposes, since the test does not result in damage to the property, as would any excavation, and provides minimal disruption of the occupant’s use of the home during the test. More comprehensive testing and evaluations are possible, and may be desirable, if greater assurance is needed.