Septic Frequently Asked Questions

For all systems except sand filters and capping fills, please call for inspection only when the installation is complete and all that is left to do is backfill.

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

We are not able to accommodate requests for partial inspections or requests for morning or afternoon inspections. By calling in an inspection request, you acknowledge that the system is ready for inspection at 8 a.m. on the day of the call. Please do not call in for inspection if the installation is incomplete. If, upon our site visit, it is determined that the system is not ready for inspection, then the permit may be subject to a reinspection fee.

Our staff plans their routes as efficiently as possible given the day's activities, but they cannot predict what situations they may encounter in the field on each inspection; some may go smoothly while others may require more time.

Permits are subject to reinspection 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 expectation is that the tank inlet and outlet be plugged, and the tank filled with water one inch up 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 twenty-four hours and the rest of the system is complete, you are ready to call for inspection. If the water level drops more than one inch in twenty-four hours, seal all leaks and perform the test again. When the water level drops less than one inch in twenty-four hours and the rest of the system is complete you are ready to call in for inspection. Please be aware that failure to properly water test the septic tank will require a reinspection.

The "pink card" is a visual aid to help the inspector locate the site; it is not the permit. This card must be posted where the access road to the site (such as a driveway) meets the public road. The idea is to provide an easy way for us to find you. Posting the address next to the road, where practical, is helpful as well.

One of the items that 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.

For additional questions please call the Soils Information Desk at 503-742-4740.

We have some subdivision records that predate the mid-1970s, which is when the Soils Section 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 the septic records are non-existent.

You may obtain copies of your septic records by completing and submitting a Records Research Request form. Or one may be faxed or mailed to you upon 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 by 100 ft (or 10,000 sq ft.) for an average 450 ft 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 ).

As a rule of thumb, we consider a one acre lot with public water, or 2 acres with a well, as the minimum lot size required for a septic system. 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 prior to issuing a septic permit, or even a building permit.

A septic site evaluation application and instructions may be accessed and downloaded online or may be requested to be faxed or mailed to you. It is important to follow all instructions carefully to ensure the application is completed in full. We cannot accept incomplete applications. A complete application includes:

• An application signed by the property owner or contract purchaser,
• A plot plan (see below for tips on drawing one up)
• A minimum of 2 and a maximum of 6 test holes in the area you would propose to replace your septic drainfield. Note, you provide these, not the County. (Only one test hole is required for a System Repair Evaluation (SRE) though two are recommended.)
• The application fee (no fee is required for SRE)
• To qualify for an SRE, the drainfield must be in failure, as represented by partially treated sewage affluent on the surface of the ground or by direct discharge into waters of the State of Oregon. This latter condition could be represented by flooded drainfield lines and distribution boxes below the level of the groundwater table.

Owners should ensure that all plumbing fixtures and lines are clean and not leaking when they suspect their septic system is malfunctioning. SREs will require the existing to have certain components exposed for inspection by WES staff.

The time varies with the season. During the busy summer building season, you should allow for several weeks. The slower winter months allow for shorter processing time. There is no advantage to testing your site during summer. During the summer we look for permanent markings in the soil which accurately indicate the depth to the winter time water table.

Note: System Repair Evaluations get our highest priority, but results may be held up if there is no evidence of failure (see last item in the above question). 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 at the Soils Counter in the 2nd floor public lobby of the Development Services Building located at 150 Beavercreek Road in Oregon City. Application materials are also available online.

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

If the site is a large acreage, focus on the area (to be) developed. 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)
• The location from two perpendicular lot lines of a minimum of two test holes (only one test hole is required for a repair evaluation) Note: the test holes must
  be in the area you propose to build a (replacement) drainfield,
• The location of the existing drainfield failure, if it is for a repair evaluation,
• All development features, if there are any,
• Any geographic feature that requires setback (creeks, ditches, escarpments, etc.)
• A path flagged to the test holes, if they are in a dense vegetation area.

Septic approvals are good indefinitely or until site conditions change in a way that would prevent the possibility of installing a code system such as:

• A well is installed in the approval area.
• The approval area is graded 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.

Septic approvals are seldom approvals of the entire lot but rather a site 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, site stability and setbacks are considered when we approve a location. However, we do not do actual percolation tests. We found in the 1960's that they didn't appear to be a valid way to predict drainfield longevity for western Oregon, with its extensive winter wet season.

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 has been approved separately.

The easiest solution is to place the septic tank near the home and pump the sewage effluent to the drainfield location. You may retest if desired.

No. The 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 desired area.

Septic systems are sized based on projected daily sewage flows. The projected daily flow for single family dwellings is based on the number of bedrooms in a home, not the number of bathrooms. The number of bedrooms is usually the limiting factor for how many people occupy a home which influences actual sewage flow volumes. This information will be requested at the site evaluation and permit stages.

Usually a bathroom addition (or any non-bedroom addition) will not cause any review of the septic system. However, some of the conditions that must be met include:

• The room is for personal use (not for a home business, for example, with a number of employees)
• It is an internal remodel or, if an external addition, the new foundations are not within 10 ft of an existing drainfield or dedicated replacement area.

If public septic records do not exist, you will be required to submit an Existing System Report prepared by a state-licensed septic installer. There is a $10.00 fee charged at the time of report submittal.

This is a complicated question and the answer is often: it depends. We will go over several scenarios below. If yours is not covered, please call the front desk at (503) 742-4740 to get a determination about what, if anything is required.

The code does NOT require the system to be upgraded if the system is in use and not currently failing and the number of bedrooms doesn't increase the flow by more than 300 gallons (4 bedrooms) or 50% beyond system capacity (whichever is less) provided:

• There is still room for an entire replacement system meeting all setbacks, should the future need arise,
• The proposed addition doesn't adversely affect the setbacks to the current septic system (5 ft to the tank, solid pipes and sand filter, if applicable, or 10 ft to the drainfield).

Note, systems can often be altered to meet setbacks, if desired, but this does require an alteration permit.

The code DOES require that the Soils Section issue an Authorization Notice if there is:

• An increase in flow up to the above limits,
• Any change in use (adding a daycare to a home, for example), or
• If a building is replaced with a like building (residential or commercial).
• A temporary second dwelling is proposed to be added to care for an ailing family member.

Authorization Notices are issued by the Soils section upon review of a Maintenance Inspection Report prepared by a state-certified Maintenance Provider hired by the owner. Important details of the Authorization Notice Process and the Maintenance Inspection Report are provided on handouts at the Soils Deskb. An application and a $215.00 fee must accompany submittal of a Maintenance Inspection Report. Please contact the Soils staff in person to ask specific questions about your site.

Soils staff are available at the Soils Desk Monday-Friday, 8 a.m. to 3 p.m., or you may ask for a staff member to call you at 503-742-4740.

Pole barns and other non-plumbed accessory structures can be reviewed and approved over-the-counter without fee if good public septic records are available and if setbacks are met without intruding into the repair drainfield area. Sites without public septic records or sites with questionable setbacks may be required to submit an Existing System Report of the septic system prepared by a state-licensed septic installer. There is a $10.00 fee for report submittal.

Owners should stop by the Soils Desk and speak in person with a soils scientist regarding the specifics of their application.

You may want to seek the services of a professional septic installer. Sometimes septic tank pumpers are able to do this work, as they are experts at finding "lost" tanks.

In this case, the septic system must be brought to code or replaced. A full code dedicated replacement area is required as well. You must apply for a Site Evaluation, expose the system (unless you just want to replace the entire system), and provide two test holes. A new construction permit will also be required.

Only a licensed septic installer-or a property owner-can install any part of a septic system.

The pipe between the building and the tank (the building sewer) must be inspected by a plumbing inspector, which requires a separate plumbing permit.

You must obtain the installation permit before you or your contractor can begin the installation.

The permit is only valid for one year, though it can be renewed for a fee prior to its expiration. This is different from other permits issued by the Building Code Division, which extend as long as an inspection is called every 6 months.

Yes, they will have to submit a new application for a permit transfer along with a permit transfer fee.

Routine maintenance, such as pumping tanks or rootering out the lines, does not require a septic permit. Replacement of components internal to the septic tank with equivalent components (e.g. Pumps, baffles, floats, etc.) is also considered maintenance.

Yes. Only routine tank maintenance does not. See above questions.

Most drainfields with average maintenance last approximately twenty to thirty years. The average life expectancy of a steel tank is seven years, though some last much longer. Modern concrete tanks can be expected to last a lifetime.

You can maintain your tank (get it pumped) or drainfield (have roots removed) without any review by the county. Replacing drainfield components (boxes, pipes, drain media) requires a permit. You may apply for a septic permit to replace a tank without a site evaluation.

If your drainfield is failing, you may not work on it until you have received an approval letter for a System Repair Evaluation (SRE). There is no charge for this evaluation, and there is a (reduced) charge for the repair permit which enables a soil scientist to review the workmanship and materials of the septic repair to ensure that they meet codes. This evaluation requires our highest priority, but while you are waiting, consider having the tank outlet capped and the contents pumped and taken to a central sewage treatment plant. Cover any affected area with inexpensive garden lime to stabilize the smell and discourage vermin and vectors. Cover any excavation with plywood and berm dirt around the edges. Apply for a System Repair Evaluation. See instructions above for Site Evaluation application and plot plans.

Assume that you will need to pump it every three to five years, unless you have your system inspected, including a check of the sludge and scum (settled and floating solids) accumulation in the tank. If solids accumulate in your tank and are shipped to your drainfield, you can shorten the drainfield longevity. As a result it is not recommended that you put off pumping your tank when it need maintenance. We recommend that gravity systems be inspected every three years and pressure distribution systems annually. For additional details, ask for our Septic System Maintenance brochure when you visit our public counter.

It is better to compost kitchen waste. Heavy use of a garbage disposal unit will add large volumes of organic matter to the septic tank which will accumulate. More frequent pumping of the tank will be necessary to prevent carryover damage to the drainfield.

A national organization called Small Flows has commissioned several university studies of septic tank additives and the results have shown that additives have no value. Some of these products actually interfered with the proper settling and removal of solids in the tank or led to permanent damage to the drainfield. The use of septic tank additives is not recommended.

We make an effort to accommodate requests for meetings for Site Evaluations, inspections and System Repair Evaluations, but it is not always possible because of work load limitations. For Site Evaluations, the site should be cleared for access, a path flagged to the test holes and the flagged path shown on the plot plan. Dangerous dogs or livestock-such as buffalo or bulls-must be penned up, and a gate key or gate code must be provided. You can request notice on the morning of the site evaluation or inspection so you can pen up animals or leave the gate open. If we cannot reach you, however, the site visit may be delayed. Also, if we see that the test holes were poorly placed in the landscape, we may ask to review more test holes in another location for no additional charge. Septic installers or consultants may be helpful not only digging the holes, but picking an appropriate location for them. An onsite meeting may be necessary during inspections to provide access to a circuit or septic tank control panel inside an otherwise unattended house.

Before a denial letter is sent, a sand filter and Alternative Treatment Technology System are considered and ruled out. Many denials are actually "conditional," requiring additional actions/information prior to final determination if the site can be approved or denied. Be sure to read the entire letter. You are usually given up to three months to complete this work or a new application and fees will be required to further pursue. Once we have visited a site, fees are non-refundable. Prior to a site visit, applications may be voluntarily withdrawn, in which case we refund 80 percent of the county portion of the fee.

Siting criteria are the same for sand filter as for the new alternatives. If you have received a "denial," the new alternatives will not enable us to issue an approval. Such areas are limited by a permanent groundwater table and are more environmentally sensitive. These shallow groundwater reserves are used as drinking water by local people so greater vertical separation between the drainfield trench bottom and effluent water table is required as a precaution against septic effluent being "recycled" into someone's drinking water.