Case Studies

Moon River Bridge Pier Protection

Most of us know the song “Moon River,” written by Henry Mancini with lyrics by Johnny Mercer for the 1961 film “Breakfast at Tiffany’s.” But few know that Johnny Mercer’s home near Savannah, Georgia overlooked the Back River, now known as the Moon River. And still fewer know that the Moon River Bridge represents one of the Georgia Department of Transportation’s most innovative developments in bridge pier protection.

Installed in 1998 and 1999 by Wood Hopkins Contracting Company for the Georgia Department of Transportation, this project is one of two bridge pier protection systems in Chatham County, Georgia, utilizing SEAPILE composite marine piling and SEATIMBER composite marine timber as the primary structural elements. The other installation, the Skidaway Narrows Bridge, was completed in 1999.

For this project, 16" (400mm) diameter SEAPILE piling and 10" x 10" (250mm x 250mm) SEATIMBER wale beams were utilized.

According to Bob Day, who served as Wood Hopkins’ project manager, the installation of the SEAPILE and SEATIMBER materials was highly efficient. “We had Seaward cut the tapered lap joints for the SEATIMBER product in the factory, so it was ready to install when it arrived on the job site. Also, we used longer lengths of the SEATIMBER material than we would have been able to use in conventional timber. This saved us time at the job site by minimizing the number of crane picks required; it also reduced the number of potential snag points in the system. We also liked the fact that Seaward cut chisel points on the SEAPILE piling at the factory, saving us time on the job site.”

Paul Liles, Jr., the State Bridge Engineer for the Georgia Department of Transportation, also serves as chairman of the AASHTO Bridge Committee’s T-21 Technical Committee on Composites. “The bridge pier protection systems at the Moon River Bridge and Skidaway Narrows Bridge were our first experience with the SEAPILE and SEATIMBER products,” he reports. “We have been impressed with their performance and very pleased with the overall results. Compared to a timber system, the all-composite system is definitely technically superior, since the composite system provides more flexibility and energy absorption, as well as a smoother sliding surface for vessel traffic. I have recommended these materials to other state bridge engineers, and we are looking forward to using them again on other projects in Georgia.”