Lake Oswego, Oregon

CITY OF LAKE OSWEGO AND LAKE OSWEGO CORPORATION REACH
BALANCED AGREEMENT FOR REPLACING THE INTERCEPTOR PIPELINE

LAKE OSWEGO – The City of Lake Oswego and the Lake Oswego Corporation have reached
an agreement to move forward on replacing the aging interceptor sewer pipeline in Oswego
Lake. On Tuesday, December 18, 2007, the Lake Oswego City Council approved the
agreement and authorized staff to complete final documents to implement the agreement.

The agreement governs the timing and the duration of the drawdown of Oswego Lake. The
agreement also outlines locations, terms and conditions governing easements required for
placement of the new pipe and for construction and maintenance access.

The Lake Corporation is the non-profit entity that manages Oswego Lake and represents
approximately 700 shareholders who own property along the lake shore, bays and canals.
The agreement provides for a six to seven month, 16-foot winter drawdown of the main lake
beginning September 2009. This allows the City to begin construction activities early, lowering
project costs and risks, and allowing for refill of the lake prior to the summer recreation
season.

Other provisions of the agreement include:
• Work in the main canal will occur in the summer through construction of a cofferdam
at the mouth of the canal allowing dewatering of the canal. Winter work in the canal is
not feasible because of issues relating to storm water runoff, project risk and floodway
regulations. Dewatering of the canal will begin March 1, 2009.
• Easements will be provided at no cost to the City for the new pipeline in the lake as
well as for access points for maintenance and construction.
• Construction periods will be from 7:00 a.m. to 8:00 p.m.
• Future drawdowns of the lake will be allowed following the construction period as
necessary for maintenance and repair of the pipeline.

Mayor Judie Hammerstad said, “I’m pleased that we’ve reached an agreement that is fair to the
residents and ratepayers of Lake Oswego and for those who live on the lake. This agreement
allows the interceptor project to start in a timely manner so we can prevent sewage overflows
in the future.”

Bill Wiley, Lake Corporation past President and Board Member said, “Our primary goal was to
make sure that sewer overflows will be reduced in the timeliest way possible. It was also important to preserve the recreation season for the majority of our shareholders and
fundamental rights of property owners along the shoreline. I think this agreement is a win-win
for both the City and the Lake Corporation.”

The interceptor is a sewer pipe that runs 14 to 21 feet below the surface of Oswego Lake. The
current interceptor was built in the 1960s and is too small and structurally unsound. Prolonged
rains can cause the system to back up, resulting in sewage overflows. Such spills are
unacceptable; the schedule that the City has outlined calls for the interceptor replacement to
be completed by the spring of 2010.

For more information contact Stephan Lashbrook, Interim City Manager, at 503-635-0215.