The Burlingame Trunk Sewer Improvement Project is a rehabilitation and modernization project of an aging sanitary sewer trunkline that runs from Multnomah Village under I-5 to Burlingame area of the City of Portland. The rehabilitation portion of the work consisted of approximately 1,645 LF of 30” Cured-In-Place Pipe lining and 225 LF of 36” CIPP lining. Existing concrete manholes, originally installed in the 1950’s, were also lined with an epoxy coating to extend anticipated service life an additional 50+ years.
The project also included enlargement and improvement of the system with the replacement of the 30” sanitary main with 410 LF of new 30” pipe and 2,500 LF of 48” pipe—both Hobas Fiberglass Reinforced Pipe. New 60”, 72” and 96” High Density Polyethylene Lined Manholes were also installed and designed to withstand the corrosive effects of sewer effluent. Additionally, unlined 48” manholes were specified for smaller diameter connections.
This project transitions from an existing force main system to a gravity system. Extensive force main and local flow diversion was required in order to ensure uninterrupted service of the trunkline during installation. Portions of the Force Main bypass involved temporary installation of 5,500 LF of 24” HDPE and over 3,000 LF of 8” and smaller pipe with up to 7 pump locations with lead and lag pumps controlled with floats and auto-dialers.
Portions of the project had very strict time constraints. Scheduling force main shutdown to install and remove the bypass system and tie in the new gravity trunkline was only permitted twice with a limited duration of only two-weeks per shutdown. These shutdowns were coordinated with Clean Water Services and seasonal limitation and maximum rainfall forecasts were imposed. Additionally, a 45 day shutdown of the I-5 on and off-ramps servicing Multnomah Boulevard were required to perform upgrades. Additional lane closures were required along I-5 Northbound and Southbound. These closures required extensive detour routes and coordination with ODOT Maintenance, Construction, Traffic, and Mobility as well as PBOT and other contractor’s performing work along the I-5 corridor. Finally, due to the densely populated and heavilty travelled area, extensive public relations activities were initiated prior to and during construction.
Upon completion of the underground portion of the work, pavement restoration, sidewalk and curb replacement and landscape enhancements will be performed.
Owner: City of Portland
Location: Portland, Oregon
Completion Date: 2012