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  1. Taking care of your septic system
  2. Inspecting your OSS

Inspecting your septic system

How an inspection will benefit you

  • Prevents pollution and illnesses - Keeping your system in good operating condition prevents sewage from entering drinking water sources, creeks, rivers, and bays used for recreation and shellfish harvest.

  • Saves money - During an inspection, a maintainer can find small problems with your septic system that are easy and cheap to fix. By fixing these problems, larger problems, like a premature failure, can be avoided. This is a cost-effective way to protect the longevity of your septic system, compared to the cost of repairing or replacing a failing system, which can be very expensive.

  • Reduces the risk of failure - Early identification of smaller problems can prevent large-scale system failures. A failing septic system may result in a sewage back-up inside your home, or expose your family, pets, and nearby waters to leaked raw sewage containing harmful pathogens, leaving families and neighbors at risk.

  • Identifies need for pumping - Rather than regularly scheduled septic tank pumping, have your tank inspected and only pumped when needed. Different size septic tanks, the use of a garbage disposal, and other factors may increase or decrease how often your tank needs pumping. An inspection costs less than pumping the septic tanks, so if you only have the tank pumped when it needs to be pumped, you can save money. Learn more about pumping your septic tank.

When you should hire an On-site System Maintainer to perform an inspection

Your maintenance schedule depends on what kind of system you have, and other factors related to your property.

When hiring a King County certified Pumper or On-site System Maintainer, know the type of septic system you have, and follow the maintenance schedule designed to help keep your septic system working for many years.

  • Gravity systems: Every three years

  • Pressure Distribution systems: Annually

  • Proprietary system such as an ATU, Orenco, drip irrigation, and other products: Every 6 months, or at different frequency if specified my the manufacturer.

  • Mound, Sand Filter, or Sand Filter to Mound systems: Annually

What happens during an inspection?

The On-site System Maintainer (OSM) will inspect your system components:

  1. Septic and pump tanks
  2. Treatment component (if applicable)
  3. Distribution system
  4. Drainfield and the reserve areas

Then, they will submit a report to Public Health about the status of your system. Smaller problems can be fixed during the inspection. If a larger fix is needed, the maintainer will work with you to identify the best solution.