Environmental Health
Septic Systems
Operation and Maintenance
  Septic System Do's & Don'ts  

Septic System Do's

1. Inspect your septic tank annually. Generally, septic tanks should be pumped every three to five years. An inspection by you or a professional may show that you need to pump more or less often. Regular pumping ensures that solids will not flow from the septic tank into the drainfield. Solids can destroy the drainfield, and once a drainfield has failed, pumping will not bring it back to life.

2. Use less water (see Home Water Savings Makes Sense [PDF]). Reducing the amount of wastewater entering your septic system may increase its life span, as excessive water is a major cause of system failure. Too much water from laundry, dishwasher, toilets, baths, and showers may not allow enough time for sludge and scum to separate, causing solids to pass out of the tank and into the drainfield, ultimately clogging the pipes. To reduce household water use:

  • Limit the use of large water guzzling appliances, such as dishwashers and washing machines.
  • Use water-saving bathroom and kitchen fixtures (such as faucets, showerheads, and toilets).
  • Spread laundry over the entire week and avoid partial loads.
  • Fix all faucet and toilet leaks promptly.

3. Direct water from downspouts and roofs away from the drainfield. Additional water from these sources may prevent your drainfield from working properly.

4. Keep cars and trucks off the septic tank and drainfield areas. This prevents pipes from breaking and soil from becoming compacted. Compacted soils can't absorb water from the drainfield.

5. Use phosphate-free detergent. Phosphorus is harmful to the environment, as it can deplete oxygen which is vital to fish and other aquatic organisms. The use of phosphate-free detergents, also helps prevent algae problems in nearby lakes and streams.

6. Install risers for easier access. Risers from the tank lids to the soil surface make maintenance easier.

For additional drainfield tips, see Drainfield Do's and Don'ts.

Septic System Don'ts

Diagram of a septic system1. Limit garbage disposal use. A garbage disposal adds solids and grease to your system, which could lead to drainfield failure.

2. Don't use septic tank additives or "miracle" system cleaners. Some of these chemicals can actually harm your on-site sewage system by allowing solids to flow into and clog the drainfield. The chemicals can also contaminate ground and surface water.

3. Don't dispose of water from hot tubs into the on-site sewage system. Large volumes of water are harmful to the system, and the chlorine can destroy important bacteria in the system. Drain hot tubs onto the ground, away from the drainfield and not into a storm drain.

4. Don't flush solid wastes into the septic system. These include diapers, cigarette butts, coffee grounds, tampons, condoms and grease.

5. Don't put strong chemicals, such as cleaning products, down the drain. Household chemicals, such as drain cleaners, paint thinners and floor cleaners, can destroy important bacteria in your septic tank and contaminate ground and surface water.

6. Don't construct patios, carports or use landscaping plastic over the drainfield. Grass is the best cover for your septic tank and drainfield. Soil compaction and paving prevents oxygen from getting into the soil. This oxygen is needed by bacteria to break down and treat sewage.

Social Media that has directed you to this web page, has been funded wholly or in part by the United States Environmental Protection Agency under  assistance agreement PC-01J18001 to the Washington State Department of Health. The contents of this document do not necessarily reflect the views and policies of the Environmental Protection Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use.

Hot Topics
Popular Pages & Links
Is your septic at risk of failing?

  • Septic Help Line
    (leave message)
  • General Questions
  • Henderson Watershed Protection Area O&M Questions
  • Building Development Center
  • Failing Systems
  • Loan Program
    (failing systems only)
  • Brochures & Workshops
This page last updated: 02/04/22