Septic Systems, Building Permits & House Additions

All residential building permits must be reviewed and signed by the Health Department before they are issued. Two issues are key to approval: Increases in potential water use and increases in lot coverage. Permits that don't increase either need no further review. Permits that increase either brings up the question "After construction, will there be sufficient room on the property, and proper soil conditions to construct a septic system that meets all aspects of the Public Health Code, should the need arise?". If the answer is clearly "yes" the permit will be signed if the current system is:
  1. Operating properly
  2. Sized appropriately for the finished house
  3. Not a cesspool
If any of these three conditions exist a septic upgrade will probably be required.

Inspections
If the answer to the original question is "maybe" the applicant will be required to show that a code-compliant system could be built before the permit can be signed. At times all that is needed to meet this requirement is a visual inspection by the Health Department. More often soil testing will need to be done by a licensed septic system installer along with the Health Department. This usually consists of one or more "Deep Test Pits" dug by a backhoe to assess the soil conditions in a potential repair area. If a suitable area can be easily identified, the permit will be signed, subject to conditions (1), (2), and (3) above. However, if the answer is still in doubt it will be necessary to hire an engineer to design a code-compliant system on the property.

Monitoring
Occasionally ground water monitoring may be required which can only be done in the spring, during the period of highest ground water. If a fully compliant system cannot be designed, the permit may still be signed under conditions that are a little too complex to delineate here. In some cases, especially on small lots and in areas of high ground water or shallow ledge rock, building permits cannot be approved due to septic concerns.

Upgrading
In many cases, when the existing septic system has not failed, it is not necessary to install the system that was designed at the time of renovations, but the design should prove useful in the event of a future system failure. That being said, it is often wise to upgrade the septic system at the time of construction in order to limit property disruption to one time period. Significant landscaping often accompanies home renovation and it would be unfortunate to disturb that work for a future septic repair.