What To Look for in a Septic System when Buying a Home


If you’re currently in the market for a new home, then odds are you may come across a house (or two) that has a private septic system of some sort, instead of utilizing the public sewer system. About 1 in 5 homes in the US use a septic system for effluent (waste) removal. If you’ve narrowed down your search and one of your potential new homes has such a system, there is no reason to shy away from it. You’ll just need to educate yourself on the items to be on the lookout for, prior to committing to anything. We’ll talk through many of these points below, so you’ll be able to spot the good, the bad and the ugly about the septic system in your new home. You can also visit the NESC website to gather more details of the mechanics behind how a septic system functions.

Gathering Important Details

Prior to beginning your visual inspection of the septic system, you should first gather some vital information from the homeowner (if they haven’t already done so via a property disclosure form). A few of the details you’ll need to know are:

  • What type of system is on the property (standard gravity, advanced treatment, pressure distribution) and where is it located?
  • How old is the septic system and when was the last time it was pumped?
  • When was the last time it was inspected or serviced?
  • What material is the tank constructed from and how large is the tank?

Performing a Visual Inspection

After gathering this information, you’re now ready to begin your visual inspection. You’ll want to keep an eye out for some obvious red flags indicating septic failure or issues, like signs of sewage seeping into the yard (either through smell or visual clues). Spots of exceedingly green grass can also mean that sewage is seeping into the yard. From the inside of the home, signs of potential septic failure include slowly draining or gurgling drains and foul odor when flushing the toilets. Dry areas around the tank and the homeowner actually knowing where the system is located, are all good signs that the system is being properly maintained.

Bringing in a Professional

Keep in mind that if the current septic system is showing signs of failure or disrepair, the costs to repair or replace a septic system can vary greatly, from $3,000 to over $30,000 based on the type of system and the area you live. A septic inspection is also likely something you’ll want to take care of prior to investing in a home. These inspections typically cost between $100-$200. You can also find more detailed information on what to expect during a septic inspection on the International Association of Home Inspectors website. If your system does need to be replaced, you’ll want to ensure you select a quality level sensor for liquids, which will alert you when there are any future issues with your septic tank. There are many models available, including submersible sensors, horizontal float switches, and mechanical sump switches. Having one of these installed will help give you the peace of mind you’ll want to ensure you system is running properly for many years to come.