Wisconsin Sea Grant Project Highlight - Corrosion

From Gene Clark, Wisconsin Sea Grant Coastal Engineering Specialist:

Several new project reports and articles (dated 2008 through 2010) and three new photos of harbor corrosion in Thunder Bay, Canada (from 2007) are now available on the Duluth-Superior Harbor Corrosion Study website from Wisconsin Sea Grant. Also included on the site is the most up-to-date fact sheet about the project.

Updated content includes:

PROJECT REPORTS:

• Duluth-Superior Harbor Freshwater Corrosion Update (presented ASCE Ports 2010), April 2010

• Cofferdam Applied Coating Trial, October 2009

• Duluth Superior Harbor Steel Structure Alternative Repair Installation & Protection Report, December 2008

• Duluth Superior Harbor Existing In-Place Coating Assessment, December 2008

PROJECT FACT SHEET:

• Accelerated Freshwater Harbor Corrosion Fact Sheet, UW Sea Grant Institute, April 2010
  

MISCELLANEOUS ARTICLES:

• "Finding Solutions To A Mysterious Harbor Corrosion Problem," Wisconsin Coastal Management Chronicle, 2009
  

All this new information and the rest of the project materials can be found here.

NEW PHOTOS:

• 2007 Field Investigations – Examples of Corrosion in Other Great Lakes Harbors & Marinas (Three Thunder Bay, Canada examples) taken by Jim Sharrow (Duluth Seaway Port Authority) can be viewed here.

Photo above is one of the new photos posted, by Jim Sharrow.

If you have any questions about the project and its results, please contact Gene Clark at (715) 394-8472 or at grclark@aqua.wisc.edu

Important study on corrosion in Duluth Superior Harbor

Long-awaited research findings just published identify one possible mechanism responsible for accelerated steel corrosion in the Duluth-Superior harbor. The peer-reviewed paper published in CORROSION, The Journal of Science and Engineering, outlines a study led by Brenda Little, Senior Scientist, Marine Molecular Processes, Naval Research Laboratory, Stennis Space Center. The study was supported by the U.S. Army Corps of Engineers, Detroit District, and the Duluth Seaway Port Authority.

The press release goes on to say, "In layman’s terms, conclusions of this study describe the process by which specific iron-oxidizing bacteria attach to carbon steel, creating a “nodule” of biomass and corrosion products. Conditions beneath those nodules (i.e. “tubercles”) cause copper dissolved in harbor water to precipitate and adhere to the iron. When ice chunks scrape against those pilings each winter, the tubercles break, exposing the copper-covered iron to oxygen which, in turn, causes the steel in those pitted areas to corrode at a faster rate…creating an almost “Swiss cheese” effect in nearly 14 miles of steel pilings and dock walls along the Duluth-Superior waterfront."

Local participants in the work in Duluth Harbor include Gene Clark, specialist with Wisconsin Sea Grant and Dale Bergeron from Minnesota Sea Grant.

Expect to hear more on this important research.

Read full text of findings.

Finding Solutions to a Mysterious Corrosion Harbor Problem

A recent article written by Kathleen Schmitt Kline and Gene Clark, both of Wisconsin Sea Grant, is featured in the 2009 Wisconsin Great Lakes Chronicle, a publication from the Wisconsin Coastal Management Program. The article details studies of the corrosion issues found in the Duluth-Superior Harbor. The results of the studies will be beneficial for all facility managers around the Great Lakes as they consider
repair alternatives for prolonging the useful lives of their docks and supporting structures.

Read the full text of the article here.

For more information about the ongoing studies on corrosion, visit Wisconsin Sea Grant's Web site.