Project Archive

ellewood three pipes stacked

Ellwood Water Treatment Plant

Industrial

Used as the carrier pipe to encase both a water line and a utility line for this water treatment plant project, Permalok pipe’s ability to support continuous tunneling, as opposed to the ‘stop and weld’ helped this project finish on an expedited schedule.

Permalok Steel Casing Pipe
homestake man sitting in pipe

Homestake Suction Pipeline Replacement

Rehabilitation

Using a sliplining application, steel pipe replaces sections of an aging concrete water system through the rough terrain of the Continental Divide.

Engineered Steel Water Pipe
kearney man adjusting pipe

Kearney Lake Road Slipline

Rehabilitation

An Innovative joint proves successful in critical sprialweld steel pipe slipline project to rehabilitate a deteriorating PCCP water main. The result is a structurally independent system with a 100-year service life.

Engineered Steel Water Pipe
old dominion aerial view hole

Old Dominion Electrical Cooperative Wildcat Intake

Trenchless

To counter act the natural buoyancy of steel, we upsized our Permalok steel casing pipe and installed internal cast iron ingots to provide sufficient weight. This new approach proved successful in this underwater intake and conveyance pipeline.

Permalok Steel Casing Pipe
welder in workshop welding

Weaverville California State Route 3 Culvert Rehabilitation

Trenchless

The project’s mountainous terrain provided a great environment to introduce our new Permalok® Auger Bore Joint, which requires less jacking force for full joint engagement.

Permalok Steel Casing Pipe
gilboa sunrise over pipe

Gilboa Dam Schoharie Reservoir Low Level Outlet

Trenchless

Northwest Pipe manufactured multiple sizes of Permalok including 108” Internal diameter, which is the largest use of Permalok® as a carrier pipe manufactured to date, for this project which supports one of the major reservoirs supplying New York City with a potable water.

Permalok Steel Casing Pipe

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