Septic and Onsite Wastewater Program

To schedule an inspection, call 503-742-4720, 24 hours a day, 7 days a week. Have your permits ready with the permit numbers associated with the inspections you are requesting, and a code for the type of inspection you need.  The code for a septic inspection is 700.  Visit the schedule an inspection page for more details.

Unless you have made prior arrangements with the department, please call for an inspection only when the installation is complete and all that is left to do is backfill. For standard systems:

• the tank  in the ground and water tested,
• the pump (if applicable) and alarm ready for operation,
• float settings set properly (pre-checked),
• pressure line or effluent sewer installed,
• trenches dug,
• drain media installed,
• boxes and header piping installed, and
• (if applicable) the groundwater interceptor trench dug with rock, pipe, and filter fabric in place. 

 Systems found to be incomplete may be subject to a re-inspection fee. 

No, unfortunately that is not possible. Our staff plans their routes as efficiently as possible,  but cannot predict what situations they may encounter on each inspection; some may go smoothly while others may require more time.

Permits are subject to re-inspection fees for incomplete installations (i.e., not ready for inspection) and when the corrections from a previous inspection have not been made and a subsequent inspection is required.

The  tank inlet and outlet should be plugged, and the tank should be filled with clean water two inches into the riser. There needs to be a clearly visible mark at the water level, along with the time, date, and your initials.

• If the water level drops less than one inch in 24 hours and the rest of the system is complete, you are ready to call for an inspection.
• If the water level drops more than one inch in 24 hours, seal all leaks and perform the test again.
• When the water level drops less than one inch in 24 hours and the rest of the system is complete, you are ready to call for an inspection.

Please be aware that failure to properly water test the septic tank will require a re-inspection.

One of the items we verify is the setback from property lines to the septic system. The property corners need to be clearly marked and the property line easily identifiable in order for us to confirm that the system meets the required setbacks.

If during the installation you find that a change is needed to the design, materials, or location of your system, contact the department at soilsconcern@clackamas.us or 503-742-4740 before making the change to ensure it is allowed under the applicable rules.  Please note that not all changes can be approved, and some may result in additional fees. 

For additional questions, please call the Septic Department at 503-742-4740. 

We have some subdivision records from before the mid-1970s, which is when we started to run the septic system program. Our records are complete for septic systems built after that. Please note that many building permits were issued based on pre-existing systems, so there may be newer homes for which there are no septic records. 

Please complete and submit a Public Records Request. We do not accept telephone requests for records. Records Research Requests are completed by WES staff each week on Tuesdays and Thursdays. A self-help area which allows you to access your records is available anytime our building is open. Please note there are processing fees for records requests (if records are found). 

You should plan on an area of approximately 100 ft. by 100 ft. (10,000 square feet) for an average 450-foot standard drainfield and drainfield repair area for a one-to-four-bedroom house. This can be reduced with some alternative systems to about 3,500 square feet. This entire area must meet all setbacks (see setback form).

Though minimum lot sizes are in part determined by the type of soil on a property, we consider a one-acre lot with public water, or a two-acre lot with a well, as the minimum lot size required for a septic system that can meet applicable setbacks. Smaller lots will probably require the system to be staked in the field to ensure it can fit with all other existing or proposed development before we issue a septic permit or a building permit. 

You may access and download a septic site evaluation application and instructions online or  request they be be faxed or mailed to you. Please follow all instructions carefully to ensure the application is completed in full. We cannot accept incomplete applications. A complete application includes the following items provided by you:

• An application signed by the property owner or contract purchaser
• A plot plan (see below for tips on drawing one)
• A minimum of 2 and a maximum of 6 test holes in the area you propose to replace your septic drainfield.
• The application fee

It varies with the season. During the busy summer building season, please allow for several weeks. During the slower winter months, we can process a request more quickly.   There is no advantage to testing your site during summer. During the summer we look for permanent markings in the soil that accurately indicate the depth to the winter water table.

• Note: System Repair Evaluations for actively failing systems are our highest priority, but results may be delayed if we are not given evidence of an active failure.
•  If you simply want to upgrade your system, you must still apply for a site evaluation if one has not been done previously.

Our applications, instruction sheets, fee schedules, plot plan instructions, and handouts on test hole construction tips are available online.

Only the property owner/contract buyer can sign the application for a septic permit, unless another agent has been authorized in writing. Use the Notice Authorizing Representative form to authorize an agent.

Show the following:

• All wells within 200 feet of the property
• A north arrow
• The scale (the preferred scale is approximately 1 inch equals 30 ft)
• For site evaluations, the location from two perpendicular lot lines to at least  two test holes. Note: the test holes must be in the area you propose to build a new or replacement drainfield.
• The location of the existing drainfield , if othere is one
• Any geographic feature that requires a setback (creeks, ditches, escarpments, etc.)

All the items listed above need to be shown, but we ask that you focus only on the area to be developed rather than the entire site.

Septic approvals are good indefinitely or until site conditions change in a way that would prevent theinstallation of  a code-compliant system such as:

• A well installed in the approval area.
• The approval area is graded or logged to such an extent that drainfield function could be expected to be impaired.
• A change in river course could reduce lot size such that insufficient acreage would remain.

A septic approval is seldom an approval of the entire lot, but rather an approval of a specific location for the septic drainfield. We look at the soil profile (color, texture, continuity of layers) as well as a surrounding area of sufficient size and slope to properly site a drainfield. In addition, we consider site stability and setbacks. However, we do not do percolation tests since they are not a valid way to predict drainfield sizing under Oregon DEQ rules.

Relocating a septic approval to a new location on the property will require a new site evaluation unless the new area has been evaluated and approved separately.

The easiest solution is to place the septic tank near the home and pump the sewage effluent to the drainfield location. Alternatively, you may apply for a new site evaluation in an area more favorable to your preferred property layout plans.

No. Home site approval does not include the site evaluation process needed for septic system approval. To obtain a septic system approval, you must complete and submit an application for a site evaluation and prepare test holes in the area planned for septic system installation.