This tied arch bridge crosses the Skykomish River at the Town of Index, Washington. It is the first steel bridge built by the county in a number of years and is the first ever metalized.

The county compared concrete and steel designs. Whether concrete or steel, the county wanted to avoid painting and the inevitable maintenance re-painting that would be needed in the future.

Metallic coating by metalizing and hot dip galvanizing were considered. Certain limitations on the galvanizing eliminated that option and metalizing became the county’s final choice.

Note: The box girders were metalized inside and out. Approximately 20,000 square feet of metalizing was safely completed in the confined space.

US Route 2 Bridge, Index, Washington

Length: 263 feet (80 meters)
Tons: 338 Tons (Approximately 56,000 ft2.)
Coating: .010”, Zinc-Aluminum (85/15)
Date metalized: July 1999
Date in service: January 2000

Report and photo courtesy of Long Painting, Inc. (Seattle, Washington) and Mr. Darrell Ash, Snohomish County, Washington.