Protecting Our Waterways

Vessel Sewage Discharge Program

This article first appeared in the newsletter The Foghorn.

America's navigable waterways are an integral part of many U.S. watersheds. These waterways play an important role in the U.S. commercial and recreational boating industries, but they also provide habitat for many types of fish and wildlife which depend upon a healthy and clean environment to survive. This article will describe the types of environmental stressors that affect navigable U. S. waterways; the impact those stressors may have on the marine and associated habitats; and the things that can be done to reduce the stressors such as controlling wastewater discharges from ships or educating vessel passengers about coastal and ocean waters.

Passenger Vessel Operators
Marine Debris
Vessel Sewage
Chemical Pollutants and Nonindigenous Aquatic Species
Coral Reefs

The health and cleanliness of waterways has a direct link to the health of the passenger vessel industry (i.e., if waterways are too polluted to attract customers, the business will go elsewhere). In this regard, passenger vessel operators are in a unique position to help in the long term prospects for the continued economic health of their businesses. In addition to assuring that vessels do not pollute the waterways, operators can educate their passengers about the value of marine ecological resources, the problems challenging the health of waterways, and what passengers can do in their normal lives to improve and protect aquatic resources. Operators can educate passengers through written material such as fact sheets, brochures, or even bumper stickers, such as the simple message that wetlands are important: No wetlands, no seafood.

The United Nations General Assembly proclaimed 1997 as the International Year of the Reef (IYOR) and 1998 as the International Year of the Ocean (YOTO).

From sources such as street litter or trash thrown overboard from vessels, marine debris is any man-made object that enters the water either through direct or indirect means. For example, a casually dropped plastic bag onto a street can be washed into a storm drain, go through the sewer system to a stream/river and eventually into the ocean where it can be deposited on beaches or eaten by an animal causing internal injury or blockage of vital passageways. It can also strand a boat by clogging intake valves and entangling propellers. More than 267 species of marine organisms are known to ingest or have become entangled in marine debris. Between 1987 and 1988, New York and New Jersey lost $2 billion in tourist revenues due to trash washing onto the beaches.

Vessel operators can help by: Adopting a policy of carry on - carry off Passengers can help by: Disposing of trash properly (e.g., no street litter); Cutting six-pack rings; and Participating in a local beach, river bank, or stream clean up

Volunteers help clean trash from the beaches.

Vessel Sewage

The discharge of sewage from vessels into the waterways can contribute to the degradation of the marine environment by introducing disease-causing microorganisms (pathogens), such as bacteria, protozoans, and viruses, into the marine environment. In addition, sewage released in the vicinity of shellfish beds pose a public health problem. Because shellfish are filter feeders, they concentrate the pathogens in their tissue, thereby causing the shellfish to be unsafe for human consumption. The most notable diseases potentially transmitted by the ingestion of shellfish contaminated with the pathogens are gastroenteritis, dysentery, infectious hepatitis, and typhoid fever. Sewage discharged from vessels can also be visually repulsive and decreases the use of waterbodies for contact sports, such as swimming, water skiing, and snorkeling.

Chemical Pollutants and
Nonindigenous Aquatic Species

Chemical compounds, such as oil and gasoline resulting from spills or leaks from vessels and/or the discharge of bilge water, can poison fish and other marine organisms. Research has shown that by-products from the biological breakdown of petroleum products can harm fish and wildlife and pose threats to human health if ingested. The ubiquitous rainbow sheen of a small gasoline or diesel spill is an all too-common sight. Although most spills are small, cumulatively they can represent a considerable problem. Since many of the petroleum pollutants float on the surface of the water and are eventually wind blown into the shoreline, they can physically cover plants and small animals, interfering with their respiration and life cycles. Birds, fish and other animals that for years have made nests and reared young within the protective surroundings of the shore have been observed to abandon nesting areas soiled by chemical pollution.

The discharge of foreign ballast water into American harbors has been the major source of invasive nonindigenous aquatic species. These new species often disperse and displace the native species resulting in major ecological damage.

(Nonindigenous aquatic species refers to a member of a species introduced to a body of water or aquatic ecosystem outside its historic or native range.)

Coral Reefs

The interaction between humans and coral reef systems has a long history. Reef fisheries have been an important food source and reef tracts have been profitable tourist attractions. The Florida Keys and its associated reef tract has an estimated yield between $30 million to $50 million per year from fishing, diving, and educational research activities. The reef tracts and associated communities of mangroves and sea grasses protect shorelines from erosion by reducing wave energy. Impact from metropolitan centers and ecotourism, marinas, and boat traffic have placed increased pressure on reef ecosystems. Physical contact from inexperienced divers, boats, and anchors leave long-term damage to the reefs, which are slow to recover.