Lake Oswego City Council, through the annual adoption of Master Fees and Charges, sets City utility rates.  The new rates are implemented on July 1 each year and take effect the first billing cycle following the effective date.  The rate increase is to help pay for improvements to the water treatment and distribution system – improvements which will allow the City to continue to provide safe and clean drinking water.

In reviewing your utility bill to understand how costs have changed, it helps to know what the typical single family home rate payer will see as an increase in a utility bill and how the bill has changed over time. There is a chart in the Master Fees and Charges booklet - Section 1 with the actual dollar amount for each service for the last few years for the typical rate payer.

To estimate your water rate increase, check out the Water Consumption Cost Calculator at: www.lakeoswego.city/finance/water-consumption-cost-calculator.

The City provides, Water, Sewer, Stormwater, and Street Maintenance

Below are useful facts about rates, how they have changed over time and the impact on the Utility Bill and other information that has impacted those rates. 


The City of Lake Oswego supplies water to more than 36,000 customers through 210 miles of pipes, 13 pump stations and 16 water storage tanks.

  •  Water rates include a fixed and a variable charge.
    • Added to the fixed charge is the tiered variable charge for residential customers. 
      This tiered water billing structure means that as the amount of water consumed gets higher, the water gets more expensive.

    • The monthly fixed charge is the price that all customers pay regardless of how much water they use.

    • Using both a fixed and variable rate based on consumption allows the City to encourage conservation, charge for a specific usage level, and ensure that revenue is sufficient to fund operating costs — including repaying Bonds as well as invest in on-going renewal and replacement of system components.


The City of Lake Oswego operates and maintains 206 miles of collection pipes,13 major pump stations, and 14 single-family pump stations.  Flows from these facilities empty into the Tryon Creek Wastewater Treatment Plant operated by the City of Portland located on Foothills Road.

  • Sewer rates are based on a fixed rate and the winter average water usage each year using the January, February, and March invoices.  Therefore, you pay the same amount of money for your sewer service every month between August 1st and July 31st. The winter average is used as the basis to determine how much sewer (from sinks, showers, washing machines and toilets) you are discharging into the system.

  • In 2006, rates started increasing every year to pay for the replacement of the main interceptor sewer line (the large pipe that collects waste from small sewer lines in neighborhoods and carries the waste to the Treatment Plant) through the Lake Oswego Interceptor Sewer Project (LOIS), which was completed in 2010. The City of Lake Oswego was required to replace the interceptor pipe due to overflows into Oswego Lake during heavy rains

  • In 2011, rates stopped increasing to pay for the Interceptor Replacement and now are increased each year at an inflationary rate.


The Stormwater programs includes management and operation of the facilities and programs that regulate the flow, quality and quantity of water that runs off of streets, parking lots, yards, away from buildings and construction sites.  Stormwater is managed by the City of Lake Oswego in order to comply with federal and state laws and to reduce pollutants entering the local streams, rivers and Oswego Lake. 

  • Stormwater rates are based on a flat fee.

  • The City of Lake Oswego’s stormwater system is not connected to the City’s wastewater system. As a result, stormwater enters receiving waters untreated. Stormwater is regulated by the 1972 Federal Clean Water Act through the National Pollutant Discharge Elimination System (NPDES) permit program.

  • Stormwater management includes establishing standards for design and construction, providing public education and outreach, environmental monitoring, pollution prevention and enforcement to meet state and federal water quality standards.

  • Stormwater operations services include catch basin maintenance, street sweeping, stormwater facility maintenance and emergency utility services.

Street Maintenance

The City of Lake Oswego maintains 172 centerline miles of streets, 12% are arterials (e.g., Boones Ferry Road); 16% are collectors (e.g., Bryant Road); and 72% are residential streets (e.g., Twin Fir Road).

Since 1999 the City has cataloged street conditions as part of a Pavement Management Program. This program requires a comprehensive pavement condition assessment for each street in the City every three years. Through the Pavement Preservation Program the Street Maintenance Fee is used for street preservation and rehabilitation.

  • The Street Maintenance Fee started in 2004. 

  • In 2009, the City Council, due to concern over the backlog of work and the importance in regular maintenance to preventing higher replacement costs, began raising the fee and recognized that the fee should have been tied to an inflationary factor since inception.

  • A typical street’s condition could decline 40% in as little as five years without needed maintenance.

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