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Wastewater Laterals

Kitchen sink and garbage disposal

Each home and business in Lake Oswego has a wastewater lateral. It is the smaller (3 or 4 inch) pipe that collects the water and waste from your sinks, showers, toilet, tubs, and any other drains that carry the wastes from the home to the larger (8 to 36 inch) City of Lake Oswego Wastewater Collection System.

Homeowners and Businesses are responsible to maintain their lateral from their home or business to the City main in a free flowing condition. This means that each homeowner or business is responsible for general maintenance such as cleaning and inspection of the line.

Who should I call if my sinks don’t drain or my toilets are overflowing?
Most common household plumbing blockages are caused by grease, roots or foreign objects clogging the service lateral from the house to the City main. Call your Plumber first and get the line cleared. If after the line has been cleared and inspected you are able to determine that there is a structural failure in the right of way portion of your lateral call the City of Lake Oswego Operations Division at (503) 635-0280. Once notified the Wastewater Department will investigate the issue and determine if the City is responsible for the blockage.

Who fixes the the lateral that is in the street or in the public right of way? 
The City of Lake Oswego is responsible to repair the lateral in the street or in the public right of way in the case of a structural failure of the lateral.

What should I do if during the process of selling my home a lateral video inspection is performed and it shows a problem in the City right of way? 
Please contact the City Wastewater Department and tell them what you have found. The City will ask that you provide a DVD or VHS that the Wastewater Superintendent can examine. If it is determined that there is indeed a structural failure in the lateral of the right of way, the City will accept responsibility for the repair. Under no circumstances should a private contractor dig up and repair any portion of the lateral in the right of way without notifying the City and obtaining permission and the the proper permits.

What should I do if I see wastewater in the street?
Please call the City during business hours at (503) 635-0280 or after hours at (503) 635-0238 to report the overflow.

What is a property line cleanout? 
A property line cleanout is a 4”round stack with a 4” sweep connected to the lateral that is installed in the ground. It has a plastic or steel removable lid that is at ground level. The property line cleanout is made of a strong plastic pipe and it is usually installed at the edge of the property line. It is usually located just behind the curb or sidewalk. The property line cleanout can be very convenient for you or your plumber in gaining access to the lateral line for clearing blockages or sending a tv camera through for assessing the condition of the pipe. Each home should have a cleanout just outside the home and at the property line. If you do not have these it is highly recommended that you have them installed.