Homeowner Training (O&M)

The Whatcom County Code allows homeowners who become certified, to complete evaluations of their on-site sewage systems (OSS), except for the following:

  • Proprietary OSS technologies, i.e. aerobic treatment units (ATU’s), Biofilters, Drip irrigation;
  • Community drainfields, i.e. an OSS that serves more than one residence;
  • OSS that have been repaired and were considered non-conforming at the time of permit issuance due to the site conditions;
  • OSS that are serving food service establishments;
  • Evaluations for the purposes of property transfers.

Property owners are not eligible to evaluate their OSS when a property is offered for sale. A Licensed Operation and Maintenance Specialist must be hired to perform these evaluations.


All gravity, non-pressurized mound (gravity mound), pressure distribution, pressure mound, and sand filter OSS may be evaluated by homeowners.

To determine your system type, refer to your OSS permit if you have a copy. The system type is usually noted on the front page.

Health Department documents related to On-site Sewage Systems (OSS) and Drinking Water in Whatcom County can now be found online.  If there is no permit available for your OSS, it is most likely a gravity system.

There are two ways to become certified to evaluate your own On Site Septic System.
A.  Homeowner Online Training, or
B.  Homeowner Training Workshops (in person)
  1. A - Online Training
  2. B - Workshop - In Person

We have developed the following Homeowner Online Septic Training (HOST) materials to facilitate online homeowner training and certification to evaluate your own OSS. Please follow the steps listed below to complete the process.

Please begin by reading the HOST study guide (This may take a minute or two to load)
Review the HOST presentation (This may take a minute or two to load - training certification form is located here)
Print the Homeowner Report of System Status (HROSS) evaluation form

After completion of your evaluation, please submit the Homeowner Report of System Status (HROSS) form and your Homeowner On-Site Sewage Operation and Maintenance Certification of completion to the Whatcom County Health Department (located within the HOST Presentation). As part of our on-going evaluation process of the Homeowner Operation and Maintenance Certification program, we are following up on the results of HROSS submittals.  WCHD staff may contact you and make a site visit to review your evaluation.

For a fee of $0.15 per page, you may also obtain hard copies of the HOST study guide and HOST presentation from our office.

OSS Operation & Maintenance Rebate Program

Directions to make Sludge Stick or Scum Stick
Please contact us at Health_EH_Parcel@whatcomcounty.us if you have difficulty accessing the documents.

Contact Us

  1. On-Site Sewage System Program
    Email the Program

    509 Girard Street
    Bellingham, WA 98225

    Phone: 360-778-6000
    Fax:  360-778-6001

    Contact Us