NATIONAL OFFICE
2020 N. 14th Street
Suite 210
Arlington, VA 22201
Phone: (703) 524-0248
Fax: (703) 524-0287
WEST COAST OFFICE:
600 1st Avenue, Suite 536
Seattle, WA 98104
Phone: (206) 624-9100
Main Menu : Estuary Basics :
Major Causes of Habitat Loss
Coastal counties account for 11 percent of the nation's (lower-48) land area, while nearly 50 percent of the entire population lives in estuary areas -- 110 million people now, a number projected to increase to 127 million by 2010. It has been difficult to control and manage the increased growth that has resulted from this population increase. Inadequate protective environmental safeguards have led to the elimination of millions of acres of habitat.
For example, in Maryland, 10 years ago every new person added to the state accounted for the loss of 1/3 acre of land; now, every new person causes the loss of 2/3 acre -- from housing developments, shopping malls, business parks, and new roads. Without effective safeguards for streams and estuary shorelines, the enormous numbers of people who will continue to settle near estuaries may well end up loving them to death.
Dredging, Draining, Bulldozing, and Paving
Thousands of acres of the many different habitats of estuaries -- salt marshes, seagrass meadows, beaches and shellfish beds -- are altered or completely destroyed every year by countless activities that do not meet environmental safeguards. Land created in bays for industrial or other activities, destroys estuary values and benefits that, rightfully, belong to all citizens of a community.
Polluted Runoff From Rural, Suburban, and Urban Areas
Storm water picks up a multitude of contaminants from roads, vehicles, lawns, and construction sites and dumps it in the nearest stream. Everything that happens on land in the watershed that drains into the estuary ends up polluting the bay and degrading its habitat. When habitat along stream channels is destroyed by poor agriculture or forestry activities or by building too close to the stream, fish die because their nesting and feeding areas are destroyed. In urban harbors especially, polluted runoff into the estuary creates "hot spots" of toxic contamination where nothing can live. An annual "dead zone" extends over 7,000 square miles into the Gulf of Mexico off Texas and Louisiana due to polluted runoff from agricultural chemicals. Airborne pollution that falls on estuaries also contributes to these problems.
Dams
Hydroelectric and flood control dams block upstream and downstream passage for migrating fish, isolating them from vital spawning and feeding areas. The construction of dams for hydroelectric power accounts for significant and ongoing loss of habitat in the watersheds of many of this nation's estuaries. Without healthy streams, estuaries do not receive their natural allocation of nutrients. The result is an overall reduction in the productivity of estuary waters. Fewer fish returning to the estuary wreaks havoc among the many living organisms in the food web that depend on healthy populations of fish.
Sewage Discharges
City and industry sewage treatment plants that do not have advanced technology dump far too many nutrients and pathogens in the water to sustain high water quality standards. Fish, humans and the native living organisms of a healthy estuary ecosystem require clean water to survive and thrive. When the treatment plants discharging into Tampa Bay were upgraded to advanced technology, the sea grasses -- 85 percent of which had been destroyed - - began to grow back, and along with them the fish and other creatures that depend on them. Across the country, water quality standards are regularly violated, often due to these types of sources. A recent EPA report noted that nearly 40 percent of the nation's rivers, lakes, and estuaries are too polluted for safe fishing and swimming.
Coastal Land Loss and Subsidence
Shifts in climate and the altering of stream channels by humans causes the loss each year of tens of thousands of acres of estuary habitat. This is especially of concern along the Louisiana coast. Here, changing the course of the Mississippi River by the Corps of Engineers has drastically reduced the yearly input of sediment to the delta estuaries, resulting in open ocean encroachment of both the estuaries and dry land. Annually, Louisiana estuaries lose about 25,000 acres to land loss and subsidence (actual sinking of the land into the water). This is also a problem in the Chesapeake Bay.
Lack of Understanding and Resulting Apathy
Many people don't understand that there is a problem or that they can do something about it. Many leaders at all levels of government have neglected their home estuary out of a lack of understanding of its importance to the local and regional economy and community traditions. Americans want clean water and a healthy environment and expect their government to safeguard these values. Protecting and restoring the nation's estuaries can only be accomplished when individuals and communities understand the many values of estuaries and the threats that put their very survival at risk. When this occurs, apathy will give way to the accountability of our political system and its ability to deliver the results citizens' demand - clean water and healthy estuaries.