Septic 101: Septic System Installations

With septic systems still in use for 25% of American households, septic system installations are a thriving business. There are many rural communities across the U.S. that do not have access to sewer and must rely on their own onsite wastewater treatment. When it’s time for you to replace or install a new system it’s best to first check with the state and county offices that oversee septic systems. Many of these state administrations will have rules to follow for how and when to install a system, and some even determine what kind of system you need. Depending on the amount of regulation in your state, your process can vary a lot in time and cost.

In Oregon and Washington a septic system installation is a multi-step process and starts with digging test pits. A licensed septic system installer should come out to your home and dig 2-6 test pits across the property (essentially a 5′ hole with steps on one side and a wall of dirt to see the layers of dirt on the other side). While the homeowner can do this process, choosing an experienced septic system installer is key because they can find the best places to dig test pits, which ultimately determine what kind of system you need. The test pits will be drawn up on a detailed map and submitted along with a site evaluation application and fee to the County.

Next, a County soil scientist will show up on site within 20 business days to review the test pits. This process is pretty interesting and you can learn a lot about your property from what they see- like if there was a recent or long ago flood or fire. Once the soil scientist has finished their evaluation they will send a letter to the homeowner and septic system installer. That letter contains a breakdown of what they found in each test pit and what can or cannot be installed in the area around each test pit. Because of this process we highly suggest a licensed installer dig the test pits as they will be able to choose the locations to get the most affordable and best performing septic system.

Once you are informed about your system options from the county, your licensed septic system installer will give you a proposal based on the counties requested system. Both Oregon and Washington provide an approved list septic systems for installations in their states. Additionally, Washington State requires an engineer on any system that requires a pressurized drainfield or pump. Once the homeowner and licensed installer have a signed proposal the installer will move forward with submitting permits and site plans to the county for approval. This approval process can take up to 20 business days and sometimes longer in the busier summer months.

Once the county has approved the permits and plans your septic system installer will schedule the installation dates with you. Most installations only take 3-5 business days, as installers understand there will be no running water in the home during this time. After installation construction is complete, the county will come out to inspect the installation and perform a series of tests to make sure the system is water tight and correctly installed. Upon final approval of the system installation the homeowner can begin using their new system.