Roosevelt and Franklin Water Main Replacement Design Project

The Ketchikan Gateway Borough is seeking civil engineering design services to replace the water mains in Roosevelt Drive and Franklin Drive with 8" HDPE water mains, install new three-way valve clusters at all side roads with cross-road extensions, replace all valving and piping in the Franklin/Roosevelt intersection, and extend HDPE mains into the PRV. In total, the project will replace mains in some 2,300-lf of roadways.

The Roosevelt Drive and Franklin Drive intersection has held the generative mains for the drinking water distribution system since the construction of the Forks Creek Dam in the 1930s. Upgrades commencing in 1983 installed 6-inch PVC drinking water piping throughout Roosevelt and Franklin Drive. Following treatment plant installation in 1989, the Borough undertook the 1991-1993 Mountain Point Service Area Water and Sewer Master Improvements Phase I-V project, entailing the construction of the booster station to provide system pressure, replacement and extension of water mains to all neighborhoods, and installation of pressure reducing vaults to create the low pressure zone along the highway. While all new mains in Roosevelt Drive and Franklin Drive are 8-inch ductile iron, the materials in the roadways remain 6-inch PVC. The 2024 South Tongass Water Utility Master Plan identified the main sizing as being an inhibiting factor for flow throughout the water system.

Of more concern is that the discontinuous nature of the ductile iron and PVC material exacerbates electrolytic corrosion: mainline valves at Rogers Pass Road have come apart on two occasions in the past five years, and cross-road mains are at high risk of pinhole leaks that would be difficult to rectify without major impacts to the traveling public. This project will extend new piping across all roadways, and provide terminal valves with the unpaved roadways.