If your home is located in King County, Washington and has a septic system, you are required by law to have the septic inspected prior to sale of your home. (Actually Pierce and other counties do have similar regulations as well.) The county website has a list of the septic requirements and resources which is helpful in this process.
King County requires that sellers have a septic inspection completed prior to sale, with a copy of the report given to the buyer and King County Public health prior to the transfer of title. The inspection and costs associated with it are the responsibility of the seller.
The inspection process looks at the operation of your septic system, examining the amount of solids, flow of effluent into the drain field and operation of pumps/baffles in the system. The result of the inspection is reported on the Operation/Performance Monitoring Report. The inspection must be completed by a licensed On-Site System Maintainer, of which there are only ~50 or so companies authorized to do this work in King County. Make sure the company you choose is on the Licensed OSM list.
In addition to the inspection, a seller must record a Notice of On-site Sewage System Operation and Maintenance Requirements with the King County Recorder’s office. This document provides notice to the buyer that the home is served by a septic system and describes the new owner’s responsibilities for maintaining the system. Your escrow/closing company will facilitate the recording process for you, but sellers and buyers need to be aware of this requirement.
The actual costs of this inspection process do vary, sometimes significantly. The inspection may reveal that the tank needs to be pumped. This depends on how long it has been since it was last pumped and the actual contents of the tank, which depend on usage and the number of folks who live in the house. Generally you won’t know if it needs to be pumped until the inspector opens the tank and takes some measurements.
Another cost that you may incur is the requirement for an as-built diagram of the system. When you construct a new septic system, a diagram showing the layout of the system in relation to the house and property boundaries is created and filed with the county. The county will likely have record of these drawings for any home constructed recently. However, if a home was built with a septic in the 60’s or 70’s, there is a chance that the as-built diagram doesn’t exist. If it doesn’t exist, you will be charged extra for the septic inspector to examine the system and create the drawing, which could be an extra $300-$500.
If you are selling a house in King County, you need to be aware of these requirements and costs. You may even want to get the inspection completed upfront, though you need to have it inspected within 6 months prior to sale of the property. Often the buyer also wants to be involved in viewing the inspection in person, so in most cases, a seller won’t conduct the inspection until they get a buyer into contract.
As a buyer, you need to make sure that you review the inspection report and receive the Notice of OSSM prior to the sale. You may also want to attend the inspection to see the system components and their operation in person. King County also has great resources for septic care and do’s and dont’s, which are helpful if you’ve never lived with a septic system before.