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Regulatory officials utilized a computer database of over 145,000 permits to evaluate the performance history of septic systems. While this database allows for differentiation of technology and its performance in different soils, this paper shows how the database can define the longevity of systems installed in a specific year. The method for defining the replacement of systems and the generation of longevity tables shows an average of less than one half of a percent loss the first 10 years, with a noticeable increase in replacement after 15 years. The increase in failure is consistent with other state reports that cite maintenance as a life-limiting factor. Both actual and projected estimates for replacement are established with the later presenting a conservative estimate of system. The estimate is utilized due to the fact that many replacement permits do not include details on the original system. The data is sufficiently detailed for an insurance company to provide a policy to cover system replacement. Over 80% of the systems provide more than 20 years of service, with homeowners responsible for operation and maintenance of the septic tank pretreatment system.