A History of Lake Oswego and Tigard's Water Systems



Lake Oswego incorporates as a City.


The City of Oswego purchases a water system from Oswego Light and Power in 1925. The system consists of 50,000 feet of pipe and one reservoir (10th Street). The water sources for the system are groundwater wells and a connection to Portland’s Bull Run source.


Tigard incorporates as a City.


Wells supply water to the Tigard area.


Poor well water quality and the desire to own a source of water leads Lake Oswego to consider other source options. The Oswego City Council initiates a study of new water source options. They consider Bull Run, Tualatin, Willamette, and Clackamas Rivers as sources. The Oswego Council selects the Clackamas over Bull Run in spite of its higher cost of development. Ownership and control of the system outweigh cost considerations.


Oswego acquires water rights on the Clackamas and designs the system still in use today.


Tigard Water District issues summer peak curtailments due to well capacity limitations to meet growing system demands and dropping water tables. In 1972, the state engineer declares the Cooper-Bull Mountain region a critical groundwater area, greatly reducing Tigard's access to further or even future groundwater rights.


Portland and Lake Oswego pipes are installed for wholesale water supply to Tigard. 


The Tigard Water District considers connecting to the Willamette River near Newberg with a “Ranney” collector well, but pulls the ballot initiative due to conflicts in engineering cost estimates.  


The City of Tigard develops future water supply plans to tap the Willamette River at Wilsonville, but is turned back by a voter initiative in 1998. 


City of Tigard joins the Joint Water Commission as a junior partner to participate in the Hagg Lake Dam Project.


The Hagg Lake Dam Project bogs down in federal ownership and seismic safety concerns.


In September 2005, the cities of Tigard and Lake Oswego complete the Water Supply Feasibility Project study. In March 2006, the two cities fund the Joint Water Supply System Analysis. This analysis investigates the technical, financial and legal issues around the potential partnership. Ultimately, the planning concludes that each city would benefit from jointly expanding the Lake Oswego water system.


Representatives from each of the two cities form a work group to further explore the water partnership. The City of Tigard withdraws from the Joint Water Commission. The Cities of Tigard and Lake Oswego and the Intergovernmental Water Board enter into a Memorandum of Understanding (MOU) developed by the work group in December.


At a signing ceremony on August 6, 2008, Tigard Mayor Craig Dirksen and Lake Oswego Mayor Judie Hammerstad officially sign a water partnership agreement between the two cities.