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All septic systems have a limited life expectancy so one can expect that they will fail at some point in time. Failing septic systems can expose you, your family and your neighbors to sewage. Sewage contains pathogens and viruses that can cause disease. Sewage can also contaminate ground and surface water possibly polluting wells, rivers, streams or lakes near your home.

Failure warning signs

  • Bad odors around the drainfield area especially after heavy water use or rainfall
  • Very wet spots with lush green grass growth over the drainfield or septic tank areas
  • Standing water in the drainfield area
  • Plumbing or septic tank back-ups
  • Slow draining fixtures
  • Gurgling sounds in the plumbing system

Trench failure anatomy
Trench failure anatomy

Trench failure detail
Trench failure detail

Trench failure - surface detail
Trench failure surface detail

Trench failure - during repair
Trench failure during repair

Take action

If you think your septic system is failing, contact one of the following professionals to confirm the location and possible cause of the failure. They will also propose a repair solution. Remember: all septic system repairs require a repair permit from Public Health - Seattle & King County.

  • A certified Installer is usually the first and best person to contact to investigate the problem but a licensed Designer or qualified professional Engineer is also available.
  • A certified Pumper/Sludgehauler can inspect the septic or pump tank to investigate causes of septic system backups or slow draining fixtures. They may recommend contacting a certified repair person if the septic system is failing.
  • Public Health - Seattle & King County can confirm the failure by inspecting the septic system. If necessary, a dye test may be performed to check if the sewage is from your septic system. Contact the Eastgate Environmental Health office for assistance at 206-477-8050.
  • Learn why jetting is not recommended as a permanent repair on old gravity systems. Jetting is a high pressure water stream to clear obstructions in septic pipes.

Repair tips

  • All septic system repairs require an approved repair proposal and a repair permit from Public Health - Seattle & King County.
  • If you have septic system problems, contact a certified Installer, licensed Designer, or qualified professional Engineer who will look at the septic system and turn in a repair proposal to Public Health.
  • A failing septic system may not have to be replaced with a new system. Your septic system professional can advise you on your repair options.
  • Pumping a failing system is only a temporary solution. While it may be necessary to have the tank pumped during the repair process, pumping the tank alone may not correct a failing septic system.
  • Learn how to clean indoor sewage spills.
  • Contact the Eastgate Environmental Health office for technical assistance and advice at 206-477-8050 (see website for specific times open.)