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Healthy Living
Septic Systems
Property owners

This page contains information for property owners.

Operation and maintenance of your system

Septic systems are usually not considered an essential part of a home. But replacing a residential septic treatment system may cost between $7,000 and $15,000!  Periodic inspection and timely repair of your system components can prevent damage to the soil and water in the ground around your home, and may extend the useful life of your system.

Septic system inspection improvements video, about 4½ minutes.


Washington Administrative Code chapter 246-272A and Clark County Code 24.17 requires homeowners whose property is not connected to a municipal sewer system to ensure that the property includes an approved, correctly functioning on-site septic system. Proper maintenance is defined in the code as:

  • Determining the level of solids and scum in the septic tank every three years.
  • Employing an approved pumper to remove septage from the tank when necessary.
  • Protecting the system components and required reserve septic area from damage by structures or materials, surface drainage, soil compaction, soil removal or grade alteration.
  • Keeping the sewage flow at or below designed quantity and waste strength.
  • Directing roof drains away from the area of the sewage treatment system.
  • Operating and maintaining alternative sewage disposal systems if directed by the County Health Officer.

Why should you maintain your septic system?

  • To protect public health.
  • To protect our drinking water.
  • To protect your investment.

 Type of system

 Frequency of inspection

Simple gravity with or without pump

Every 3 years

Pressure distribution*

Every 2 years                            *Clark County received a waiver from WA-DOH for inspection every 2 years.

All alternative systems (sand mounds, ATU, Glendons, etc.)

All food establishments

Note: Some systems are so complex the manufacturer recommends inspection more often for the first 2 years; be sure to meet the conditions of your warranty.

All systems

Ensure that a current report of system status is on file with Clark County Public Health when a property served by anon-site septic system is offered for sale.  The report of system status is considered current for purposes of this subsection if it was completed within one (1) year of the date of sale.


Maintaining your septic tank

The lack of septic tank maintenance can cause sewage to back up into your house or solids to overflow to the drainfield. Once solids overflow and leave through the tank outlet, they can quickly clog a drain field to the point that a new one is required. Most septic tanks need to be pumped every three to five years, depending on the tank size and the amount and type of solids entering the tank. The inspection of the sludge and scum levels is the only way to determine when a tank needs to be pumped. This is not necessarily a pleasant task, but can be done relatively easily. Septic tank pumping firms are available to perform the inspection. For more information please see our Guide to the proper care and maintenance of your on-site septic system. (PDF)

Local on-site septic system regulations

The Clark County Board of Health adopted Ordinance 24.17, On-Site Sewage (septic) System Rules and Regulations of Clark County Public Health, in October 2007 during a public hearing.

Can resident homeowners do their own inspections?

If it's a simple gravity system, yes!  The homeowner must attend a workshop at Public Health and pass the operations & maintenance (O&M) test.  An inspection by the resident homeowner can be carried out no more than every six (6) years (every other inspection is to be done by a certified O&M specialist). The inspection reporting form will be provided at the workshop.

Well and Septic Inspection and Maintenance for Homeowners

Learn how to correctly inspect your home septic system to keep your investment working properly. At the conclusion of this presentation, take the Public Health Operations & Management test to become certified to do your own septic inspections (gravity fed only).

To be added to the Septic Insepction Certification Class waitlist contact:
Eric Lambert at (360) 397-6060 x 5729 or

Help for failing septic systems

Financial assistance is available for homeowners with failing septic systems in need of repair or replacement. Please contact Janielle Eveleigh-Tomlin, Clark County Community Services, at (360) 397-2075 ext. 7811 for further information regarding the Housing Rehabilitation Loan Program (PDF).

Example of groundwater contamination by cesspool (30-second video).


Certified/licensed professionals

Our office does not recommend any particular septic operation and maintenance specialist, but does provide a list of persons/businesses who are currently certified with Clark County Public Health to conduct septic system inspections. Questions? Call (360) 397-8428.

More information


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