This cost depends on whether a public sewer is adjacent to your property and suitable for your use. A public sewer is usually eight inches or more in diameter and may be located in a street or a sewer easement through private property. If public sewer is available, you may owe a reimbursement (called a latecomer’s charge) to the installer of public sewer facilities such as pump stations and pipes serving your property. You also might be required to extend the public sewer pipe, at your expense, across all frontages of your property if it is not installed there already.
If no public sewer is available, you would be responsible for extending the public sewer from the end of the City’s existing system to and along the frontage of your property prior to making a connection. The cost to extend a sewer pipe varies, depending on the length of the project, difficulty of the terrain, soil type, need to acquire easements, the amount of engineering work required, pipe and backfill materials specified, methods of construction employed, and surface restoration requirements. In rare cases, you may also owe a latecomer’s charge as described above. Construction of a public sewer requires permitting and inspection by the City’s Community Planning and Development Department at 360.753.8314. To receive a permit, you would be required to submit design plans, conforming with the City’s Engineering Design and Development Standards, for review and approval.
The cost of a sewer extension project can sometimes be shared with your neighbors who also would benefit from the availability of a sewer adjacent to their properties. Longer, shared sewer projects allow for an economy of scale in design and construction that reduces the cost per property, as compared to each property owner sequentially installing a separate, smaller sewer extension project. The City will be constructing a limited number of neighborhood sewers in priority areas.