The On-site Septic/Sewage Disposal Program is designed to provide sewage treatment and disposal for homes not served by a community sewer system. Drain-fields must be properly designed and installed for two reasons:
Improper disposal of sewage causes many diseases in humans.
The approved area must not be disturbed. The approvable area can be drastically reduced when setbacks are inadvertently created. Setbacks are required distances to your septic tank and the disposal field from such things as wells, creeks, property lines, and banks. A complete list of setbacks is included in your application packet: Current Septic Application (PDF). If you are not personally signing the Septic Application, you must attach the following Letter of Authorization (PDF)
The following list has been put together by Environmental Health for your reference. For a complete list of licensed installers throughout the State of Oregon you may visit the Department of Environmental Quality's website. List of Local Licensed Installers (PDF).
Once your permit has been issued and your system has been installed, our Environmental Health Specialist will need to review the As Built Diagram. See attached Installers Packet (PDF). Your installer will need to provide a "to scale" drawing along with a list of materials used.
Maintain your system. Don't ignore it. You will spend a lot of money to install your septic system. Replacing it will cost you even more.
Consider optional equipment that may improve the performance and prolong the life of your system. The Environmental Health office can provide you with information on some of the latest technology that is available to you.
Septic System Maintenance Info
EPA Homeowner's Guide for Septic Systems
These printed publications can be obtained from:
Benton County Environmental Health
(Enter through the Polk Avenue door)
530 NW 27th St.
Corvallis, OR 97330
Phone: 541-766-6841
DO know where your approved area is. Marking the corners is a good idea.
DON'T allow construction activity on or near your approved area that will cause your approval to be revoked. Excavations, pushouts, well drilling and other activity will require setbacks from your system.
DO make sure that your installer has a copy of the installation permit on the job site at all times. You will be provided with an installer's packet of materials at the time your permit is issued.
DON'T remove soil from or add fill to the approved area unless required to do so in your permit.
DO take care of your septic system. Have the septic tank pumped every 3 to 5 years. Keep livestock and vehicles off the disposal field.
DON'T plan on building over either your approved initial or reserve areas. You may not have any other suitable soils on your parcel.
DO keep a copy of your site approval, installation permit, and certificate of satisfactory completion for your records.
For additional questions regarding your on-site sewage disposal system, call Benton County Environmental Health at 541-766-6841.
Download an on-site septic application for Benton County: Current Septic Application (PDF).
We also have a list of local licensed installers (PDF) who have provided us with their contact information. Please note, we do not recommend or endorse any particular installer.
Common Questions about the Construction Season
Site Approval – Before you can begin building your home, an approved area for both an initial and a replacement septic system will need to be identified on your parcel. The site approval will detail the type of system required for your parcel, its location, known setbacks to the system, and requirements that you will have to meet before a permit can be issued to install the system.
When you fill out your on-site sewage disposal system application packet, make sure that you fill out all information required for a site feasibility study. An incomplete application will delay the process.
Line Up an Installer – If you haven't done so already, we recommend that you secure the services of a licensed septic system installer. The sooner you start working with him or her, the better. Your plans may be delayed if you wait until the last minute. A list of local licensed installers and consultants is included with the application packet.
Installation Permit – When you are ready to begin installation of the system, you must first apply for an installation permit. You'll need to use an additional application packet. The installation permit must be issued prior to beginning construction of the system. The permit is specific for your parcel and your building proposal.
Certificate of Satisfactory Completion – This certificate will be issued only after all of the permit requirements have been met. This is your OK to start using your system.
Benton County Environmental Health works to protect us against environmental factors that may adversely impact human health or the ecological balances essential to long-term human health and environmental quality, whether in the natural or man-made environment.