The Onsite Program is responsible for the safe treatment of and dispersion of residential wastewater and non-industrial commercial wastewater in areas of Chelan & Douglas Counties to ensure the safety and sanitary disposal of septic effluent including greywater.  Onsite Environmental Health Inspectors permit all Chelan & Douglas County Septic Systems and licenses all Onsite Septic System Service providers (Installers, O&M providers, and Pumpers).

Onsite Septic System Permitting Process

 

1.       Site/Soil Evaluation

The evaluation of soil and site characteristics will determine the suitability for an OSS on the parcel or lot.  The results of the evaluation will provide the type of Onsite Septic System required (Gravity, Pressure Distribution, Alternative or Advanced Treatment System) and the soil loading rate, including other landscape and environmental factors.  Site/Soil Evaluations must be completed by a Licensed Designer or Professional Engineer.  CDHD does provide this service, but we do not provide the test pits or provide the Septic System Design.

2.       On-Site Septic System (OSS) Design

A septic system design must be prepared by a Licensed Designer or Professional Engineer. Submit design with your application.

3.       Septic Design Approval & Installation

On-site Inspectors will review the submitted septic system designs with soil evaluation results.  Water availability is required for the issuance of septic permits per RCW 19.27.097. A separate private water review application or public water will serve letter is required with application.  Application review time will vary from 2-3 weeks depending on the workload. Per RCW 70.05.074 must review application within 30 days. Permits will only be issued when designated Licensed Installer has been established.  Septic systems must be installed by Licensed Installers.

4.       Inspection

All Final inspections must be conducted by CDHD. Inspection requests must be submitted via email to inspections@cdhd.wa.gov.  EH asks for 1 – 2 business days advance notice of inspections so the EH Inspectors can schedule accordingly. The EH Inspector will reach out to Designated Installer to confirm inspection date and time. If there is no response in 2 business days, contact our office at 509-886-6400.

 

Service Providers & Licensed Designers

Chelan-Douglas Health District requires licensing of individuals for septic system work in both Chelan & Douglas Counties.

 

Forms & Resources

As-Built Form

Test Pit Construction Guidelines

Site Plan As-Built

On-Site Sewage Systems State Regulations (WAC 246-272A)

Table IV – Minimum Horizontal Separations