Frequently Asked Questions

Where do I start the process of installing a septic system?

Begin with the basics, have the site and soil evaluated to ensure the lot meets the minimum county requirements. If it does, the next step is having the system designed by a licensed septic designer.

How do I know the right system for my property?

The appropriate septic design for your lot will be determined as a result of your site and soil evaluation.

What is the average cost of having a septic system designed and installed?

The cost can vary anywhere from $5,000 to $20,000 or more dependant upon system type and site specific conditions. A ballpark range for different system types can be provided once your site has been evaluated.

How long does it take to get a septic system installed and approved?

There are two phases involved in completing your OSS? Design and Construction.

Design Phase:

Once the design (site application) has been submitted for County review it can take from 2-4 months to receive your response. Once the design has been approved you can obtain your building permit.

Construction Phase:

After the plumbing stub has been installed in your home you are ready to hire a Master Installer to construct your system. The installer will contact us to request a ?stub out inspection.? This site visit will verify that all has remained the same at your site in respect to the OSS design. We will then instruct the County to release the installation permit to your installer. After construction of the system is complete a ?pressure test? will be conducted to verify proper function of your new OSS. Final documentation, or your as-built package, will then be compiled and submitted to the County for final review and approval. Once approved you can obtain your final occupancy permit and move in.

Time frames for construction can vary based on system type and installer scheduling. A minimum of 30 business days after a successful pressure test to final as built approval is typical.

Who can help me through this process?

A qualified designer will work with you through design and construction of your OSS.

How do I select the right company to design & install my system?

Make sure you're working with a company that values you as a client. Do they return your calls in a timely manner? Are they willing to take the time to answer all of your questions? It's good to work with a company that keeps up on current system developments and alternative technologies. In other words, are they active in continuing education? Lastly, check references!

What are my responsibilities throughout the process?

Communication is key. If you're not sure about something, ask. After you hire a designer, you will also need to hire an installer. It's important to hire quality professionals. We can provide a list of our recommended installers upon request.

Do I need to worry about permits?

No. Everyone you hire to design, install and inspect your septic system will submit permit applications as a regular part of their responsibilities.

How do I maintain my septic system?

The state of Washington requires all septic systems be maintained. The frequency of on-site maintenance and inspections will vary from county to county and with different systems. You will receive an owner's manual with your system that will describe the required maintenance for your system.

What are the do's and don'ts for living with a septic system?

There are several general do's and don'ts for your system, as well as some that may be specific to your particular design. Your owner's manual will provide a list to help you properly care for and use your septic system.

Are there terms and jargon I should know and understand?

Throughout the process of having your septic system designed and installed, you may hear many terms you are not familiar with. Below we've provided a list of the most common terms and their definition to help you communicate more effectively and have a better understanding of the process.

Terms

As-Built

A scaled drawing showing the location of all OSS components (septic tank, pump tank, reserve area, etc.)

Drain Field

The main treatment component of most OSS. Effluent passes through a series of gravel filled trenches prior to entering the groundwater system. See our On-site Sewage Systems page for more information.

Effluent

The sewage that has been clarified in a septic tank

Filter Baffles

Devices within the septic tank that separate the floating scum layer from the liquid layer, promoting solids to settle at the bottom of the tank where they belong.

Gravity System

A wastewater treatment system that uses gravity to move the effluent through the drain field, without the use of pumps.

Mound System

A wastewater treatment system built above the original soil surface and appears as a rise or berm in the yard.

OSS

An abbreviation for your On-site Sewage (or Septic) System

Pressure Distribution System

A wastewater treatment system that pumps effluent through a series of gravel-filled trenches supporting small pipes.

Reserve Area

A designated replacement area that must be protected for future use when the existing OSS area needs additional room or replacement.

Sand Filter

A wastewater treatment component that pumps effluent through a sand filled bed. This is a secondary treatment component used in conjunction with a drainfield for final treatment of the effluent. See our On-site Sewage Systems page for more information.

Scum Mat

Lighter solids that float, such as grease, fats, and oils that do not decompose, but accumulate as a layer at the top of a septic tank. This mat must be removed by periodically pumping the tank.

Sludge Layer

Heavy solids that settle to the bottom where bacterial action produces digested sludge and gases. This layer must be removed by periodically pumping the tank.