Description

Thomas/Wright, Inc. completed planning, preliminary engineering, design, contract administration, and surveying for this project to replace the existing combined sanitary and storm sewer system serving 1,100 acres of developed Oregon City. The replacement of the existing combined system required the construction of approximately 13 miles of sanitary sewer.

As a first order of work on the project, the firm prepared a planning and engineering design report which reviewed previous planning studies, analyzed the existing system, detailed a preliminary design of a new sanitary sewer system, and recommended construction phasing.

The firm designed 67,000 feet of sanitary sewer, 9,100 feet of storm drain, an approximately 88 foot railroad overpass structure which supports a 36-inch storm drain pipe, an underwater crossing, 2,060 feet of pressure sewer, a bored crossing under Highway 99E, and modifications to an existing pump station. The railroad overpass structure and underwater crossing required coordination with Southern Pacific Railroad Company, Portland General Electric, Smurfit Newsprint Corporation, U.S. Army Corps of Engineers, and Oregon Division of State Lands for permits and right-of-entry. ODOT permits were also acquired for work along or crossing Highway 99E.