In the present study, the overall economic impact of hull fouling on a mid-sized naval surface ship (Arleigh Burke-class destroyer DDG-51) has been analyzed. A range of costs associated with hull fouling was examined, including expenditures for fuel, hull coatings, hull coating application and removal, and hull cleaning. The results indicate that the primary cost associated with fouling is due to increased fuel consumption attributable to increased frictional drag. The costs related to hull cleaning and painting are much lower than the fuel costs. The overall cost associated with hull fouling for the Navy's present coating, cleaning, and fouling level is estimated to be $56M per year for the entire DDG-51 class or $1B over 15 years. The results of this study provide guidance as to the amount of money that can be reasonably spent for research, development, acquisition, and implementation of new technologies or management strategies to combat hull fouling.

Primary‐effluent wastewater from the Allegheny County Sanitary Authority (Pennsylvania) was used as a surrogate for combined‐sewer‐overflow waters contained in the sewershed. Pathogens contained in combined‐primary‐effluent wastewaters or combined‐sewer overflows (CSOs) may pose a human‐health threat to those coming in contact with such receiving waters. Polymeric ultra‐ and nano‐membranes can be used to capture these microorganisms from CSOs. This research investigates the ability of polymeric hydrophobic and hydrophilic membranes, ranging in pore size from 0.2 to 0.8 μm, to remove pathogen‐indicator organisms (Escherichia coli, enterococcus, and fecal coliforms). Membranes, with pore size 0.45 μm and smaller, were able to reduce the bacteria levels to nondetectable levels, with the sole exception of one membrane with pore size 0.3 μm.

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