image of Corrugated Aluminum Alloy Pipe

Are you looking for a culvert pipe to stand up to salt and brackish water environments?

Corrugated Aluminum Alloy Pipe (CAP) has superior corrosion resistance and excellent abrasion resistance, which allow it to be installed in a much wider environmental range than traditional galvanized corrugated metal pipe. The rugged 3004-aluminum alloy core is clad on both sides with a 7072-aluminum alloy, which provides an anodic protection to the core alloy. The cladding shields the core alloy both physically and electrochemically against corrosion. This is primarily due to a thin, tenacious, inert oxide barrier that forms on the metal surface when exposed to oxygen. The oxide barrier appears on the pipe surface as a grayish-white coating that will build up over time.

CAP performs very well in salt and brackish water applications. Let’s look at the inground performance of several culverts installed over fifty years ago in hypersaline conditions.

Bonneville Salt Flats, Western Utah

The Booneville Salt Flats, located west of the Great Salt Lake in Utah have a water and soil environment where very few life forms can exist. The Great Salt Lake Basin is considered to be a hypersaline environment. The area can have as much as 10 times the salt concentrations of the Pacific Ocean. The high levels of salts in the water and soil are prohibitive to many types of culvert pipes including reinforced concrete pipe and most types of corrugated steel pipe. The main photo shown above is an aluminum pipe arch that was installed under Interstate 80, Utah, nearly forty years ago.

Several Corrugated Aluminum Alloy Pipe culverts have been installed in the Booneville Slat Flats at various locations including under Interstate 80. The first corrugated aluminum pipe installation was in 1962.


After 57 years of service in standing salt, this aluminum pipe located 9.4 miles east of Wendover, UT, is still going strong.

After decades of inground performance, Corrugated Aluminum Alloy Pipe has shown to perform extremely well in this saltwater environment. All culvert pipes, including the original installation in 1962 are still in use with no apparent corrosion.

I would encourage you to specify Aluminum Alloy Pipe for your next drainage project in salt or brackish water environments.