Septic Systems

For questions about septic system permitting, please contact the Snohomish County Health Department at 425-339-5200.

Lakewise Slide2

Here's the problem

Over 78,000 homeowners in Snohomish County rely on septic systems. If these systems are not properly maintained, they can cause serious problems. Failing systems:

  • Expose your family and pets to harmful bacteria and pathogens
  • Contaminate drinking water wells
  • Pollute lakes or streams with harmful bacteria and nutrients that feed algae

Protect Your Investment and Your Lake - Be LakeWise

The good news is you can make a difference by taking a few simple steps to ensure your septic system runs properly for years to come. Regular septic care is not only good for your lake but also your wallet – a little maintenance goes a long way toward preventing failures and costly repairs. 


Make these LakeWise Clear Choices for septic systems: 

  • Attend a FREE septic system care workshop (now available on-demand)
  • Have an up-to-date inspection by a licensed septic care provider* 
  • Commit to future inspections at the frequency required by your system type*

Being LakeWise pays off – you can also earn up to $500 in septic system care rebates by attending a free septic system care workshop. 


*Find the required inspection frequency for your system type in the Snohomish Health Department's guide to Monitoring and Maintenance Frequency.

Step 1. Look Up Your Septic System Type and Records

Using the Snohomish County Health Department's Online RME database, you can review your "As-Built" drawings and records to find your:

  • Type of system and components
  • System location on your property
  • Service history and septic applications

Learn how to find your system's "As-Built" drawings by watching this video or reading these instructions. Then, download the guide(s) for your system type in the table at the bottom of this page.


Step 2. Practice Proper Septic System Care and Maintenance

The Homeowners Guide to Septic Systems provides you with everything you need to properly care for your septic system. Learn what to keep out of the drain, how to find and work with septic professionals, how often to inspect your system, landscaping options and more. 

Homeowner's Guide to Septic Systems


Step 3. Take the Septic Care Workshop

Visit the Snohomish County Health Department's Savvy Septic Program website to take their free, online workshop. This workshop is now available on demand so it can be taken at any time! Plus, taking the workshop makes you eligible to earn up to $500 in rebates (see Financial Incentives for Septic Care below). 


Be sure to send your workshop "Certificate of Completion" to lakes@snoco.org if you are working towards having your property become LakeWise Certified. 


The Snohomish Health Department's Savvy Septic Program is your one-stop-shop for septic system care. In addition to workshops, the program has rebates for septic system inspections, riser installation, pumping and minor repairs. Grants and low-interest financing options are also available for major repairs. You can sign up to receive a quarterly e-newsletter with great tips and info for homeowners with septic systems.

Care Guides by Septic System Type

In the table below, find your system type and download the corresponding care guides.


System Type / Component Corresponding Guide & Example Inspection Report
GravityGravity System Guide 
Gravity Inspection Report 
Pump Chamber & Alarm Pump Chamber & Alarm Guide 
Low-Pressure Distribution (LPD)LPD System Guide 
LPD Inspection Reports
Drip DispersalDrip System Guide 
Drip Inspection Report 
MoundMound System Guide
Mound Inspection Report 
Sand FilterSand Filter Guide 
Sand Filter Inspection Report
Sand-Lined Bed (SLB)Sand-Lined Trench Systems
Sand Filter Inspection Report
Aerobic Treatment Unit (ATU)ATU Guide
ATU Inspection Report 
Proprietary SystemFind and strictly follow the manufacturer’s operation and maintenance manual 
Example Proprietary Inspection Report