Navy ships generate a variety of wastes that can be classified as emulsions, including bilge water containing oil, blackwater, graywater, shipboard “industrial” waste, and solid residuals from existing treatment systems. The need for shipboard wastewater treatment for military vessels is driven by existing and anticipated regulations. The Clean Water Act of 1977 prohibits the discharge of untreated sewage in restricted waters. The Uniform National Discharge Standards (UNDS) will require implementation of marine pollution control devices to control graywater discharges. In addition, UNDS will limit the oil content of liquid discharges to be no greater than 15 parts-per-million. When regulations cannot be met, holding tanks are used to store certain types of wastewater until they can be transferred to an in-port facility. With impending changes in regulations, the traditional holding capacity may no longer be adequate, resulting in restriction of operations in littoral waters which are important to the U.S. Navy.