"Seven-Year History of a Fine-Mesh, Floating, Anchored Barrier for Exclusion of All Fish Life Stages in the Estuarine Waters of a Tidal River"

A fine-mesh (0.5 mm AOS) exclusion barrier (“Gunderboom MLES”) was installed in the Taunton River, North Dighton MA during the spring of 2008 to exclude fish life stages from the intake for a newly constructed desalination plant. Installation of the system during spring 2014 represents the seventh consecutive year of seasonal operation, providing a reasonable basis for consideration of the operations and maintenance requirements, repairs and refurbishments required, as well as modifications from the initial design that we determined to be necessary or advantageous. Exclusion results, though generally good, were somewhat variable over the years of operation. Some of the variability can be accounted for by specific events while for other there can only be conjecture.

The site characteristics and exclusion system design are summarized. O&M activities, repairs and refurbishments are described and presented on a timeline and also summarized for each year through refurbishments made for year seven. On the same basis, specific improvements identified and made are discussed.  For these activities, type and level of effort are enumerated and material costs quantified.  Finally, a brief overview of exclusion effectiveness as presented in required annual reports to the regulatory agencies is given.