to report a sewer backup

Call (425) 398-4400 (24-hour) to report sewer back-up emergencies.

Northshore Utility District (NUD) can assist customers by determining if a problem exist in the private plumbing or if it is located within NUD’s public system. District personnel are not authorized, or licensed, to make repairs on private plumbing systems however, they are able to provide expert advice and 24-hour emergency assistance free of charge.

In addition, NUD does not charge for sewer repair permits. Obtaining a sewer repair permit ensures work is performed properly and the repair record will be maintained with the property. NUD also provides a list of qualified contractors approved to work in the local area. For permit assistance contact NUD’s engineering office at (425) 398-4401, or email

Responsibility and Ownership

NUD is responsible for maintaining and operating the sewer system located in the public Right-of-Way. Sewer piping located on private property is considered an extension of the customers plumbing system and is the responsibility of property owners. Since the private plumbing connects directly to the public system, permits are required anytime the private system is worked on or modified.

a graphic of sewer pipes indicating what part of the sewer line is owned by the property owner and which is owned by the water company

Preventing Sewer Backups

Most sewer back-up originate in the private plumbing system. They are frequently costly and can create significant issues. The following provides important information to help prevent sewer back-ups.

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