What Is a Septic Test?

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Although some home buyers turn up their nose at the thought of purchasing a home with a septic tank, more than 1 in 4 households rely on septic systems for fresh water and sewage maintenance.
But what do septic tests consist of? If you are the proud owner or the potential owner of a septic tank, here’s what’s in store!

What happens during a septic test?

Septic tests are meant to measure the level of functionality within your current septic system through a series of distinct examinations. There are two different methods of conducting septic tests: visual dye tests and full inspection tests.
Visual septic dye test: As the quicker, less expensive, and less invasive method of septic system inspection, visual septic dye tests are used to identify problems within your septic system without having to dig up your backyard. A home inspector or other hired professional will open at least three plumbing fixtures in your home, add colored dye to the water, and allow it to run through the system for 30 to 45 minutes. Then they will examine your lawn to identify any leaks, backups, surface breakouts, or other issues. 
Averaging around $100, a visual septic dye test is a simple and cost-effective way to assess the status of your septic system without any excavation. These examinations are accepted by most lenders and can even be conducted as part of a general home inspection. However, if you conduct a visual septic dye test and find an issue, you may have to conduct a full inspection to uncover the root cause.
Full inspection: Despite being the more expensive, invasive, and time-consuming option, conducting a full inspection (or destructive inspection) is sometimes necessary to get comprehensive insight into your septic tank’s condition. These examinations can take anywhere from 6 to 8 hours (or sometimes even longer) to complete, so make sure you are prepared to block out an entire day so that your home inspector or hired professional can get everything done in a timely fashion. Here are the steps professionals typically follow:
  • Find the tank. If your septic system has not yet been mapped, a hired professional will have to manually locate the septic tank and its access point (typically both in your backyard).
  • Conduct a visual exam. Your inspector will look for any visual signs of lawn damage that may indicate septic system failure (i.e. any leaks, wet spots, and/or backups). After this is completed, your inspector will assess your septic tank directly, checking whether the layers of scum, gray water, and sludge are compiling and separating properly.
  • Drain the tank. In order to conduct a thorough examination of your septic system, your septic tank must be excavated and completely drained. After your septic system is pumped, a hired professional will assess the inside of the tank for any leakage, cracks, or other small signs of damage to its interior. This is also the perfect time to examine the effluent screen (a filter inside your septic system) to ensure it is still properly keeping solids and other debris out of the leach field (or drain field). 
  • Perform additional assessments. If there are any signs of damage in your septic system (whether internal or external), your inspector will perform a deeper dive into the affected area to discover its cause and determine how to fix it. Drain field repair is a common issue, as parked cars and deeply rooted trees often negatively impact the delicate pipes in this area, and may result in the need for additional tests or examinations.
  • Replace the soil. Because destructive septic inspections require the septic tank to be excavated, a professional will cut out and replace a section of your lawn.
Get the results. After your septic test has been completed, your hired professional will inform you of any damages or issues that were found while identifying the proper steps/channels for repair. Septic system damage can be expensive to fix, so it’s in your best interest to create an effective maintenance plan to keep it running smoothly for decades to come.