Wednesday, February 8, 2023 / by Amy Brown
I receive a lot of questions about septic systems so I wanted to address those today. City sewer service is very spotty in our area due to our infrastructure so septic systems are fairly common, even in some urban areas.
For parcels without city sewer availability or parcels in the county, you will need to install a septic system. While these systems are fairly easy to maintain, there is an extensive process for installation and determination of where the system can be located on the land. Also, not all properties are suitable for a septic tank.
In order to make this determination you have two avenues, you can hire a county inspector to come out and perform the evaluation or you can hire a private soil scientist. There are pros and cons to each. While hiring the county inspector is less expensive, it usually takes a very long time to get on their schedule and then afterwards to obtain your report, generally greater than 2 months. Since it would be unwise to consummate a land transaction without this information, that means extending out your due diligence periods and closing time for an extended contract term. Most sellers are unwilling to keep their property off of the market for months while you are making that determination. In order to circumvent this issue, hiring a private soil scientist is a much better avenue for all parties involved. A soil scientist costs a bit more but they can generally get to your project within 2 weeks and provide a report within a few days following. This will allow you to make an educated decision on this aspect of your sale much sooner.
What does a soil scientist do?
For residential building, soil scientists complete what we know as a “perk” test. A perk test determines a parcel’s ability to support an onsite sewage disposal system, the optimal areas for that system, and the type of sewage disposal system needed. Soil scientists will also determine whether any of your land is within a flood prone area and where the stormwater runoff goes so that you can predict the optimal building site for your home.
There are several different types of septic systems but the conventional system is most commonly used in North Carolina. The tank itself is precast concrete measuring 9’ x 5’ and buried completely underground. The average tank holds 1,000 gallons, however, tank size is determined by the number of bedrooms in the home that it services. In addition to the tank, there is also a drain field that allows the liquid sewage to flow down the lines, into gravel, and then down into the soil where contaminants and bacteria are filtered out. The type of soil available will determine the size of the leach, or drainage, field. Homes that require a septic system will tend to need a much larger lot, generally ½ acre or more.
Septic tank maintenance is fairly easy and most homeowners say that it is not much different than the city system. Things that you will need to be more careful of with a septic system are:
Do not put too much water into the septic system; typical water use is about 50 gallons per day for each person in the family.
Do not add materials (chemicals, sanitary napkins, applicators, and so on) other than domestic wastewater.
Restrict the use of your garbage disposal.
Do not pour grease or cooking oils down the sink drain.
Have the solids pumped out of the septic tank periodically (approx. every 3 years).
Keep automobiles and heavy equipment off the system.
Do not plan any building additions, pools, driveways, or other construction work near the septic system or the repair area.