THE VIRGINIAN-PILOT
Copyright (c) 1995, Landmark Communications, Inc.
DATE: Saturday, October 14, 1995 TAG: 9510140264
SECTION: LOCAL PAGE: B1 EDITION: NORTH CAROLINA
SOURCE: ASSOCIATED PRESS
DATELINE: RALEIGH LENGTH: Medium: 96 lines
Millions of fish floating dead on the surface of the Tar-Pamlico and Neuse rivers have become a common sight this year. But large-scale fish kills remain a rarity in neighboring states.
Blame North Carolina's Outer Banks, researchers say.
The geographic feature that helps keep the Atlantic Ocean's worst storms out also serves to keep in polluted waters that flow from deep within the state.
``It's hard to believe, but it's true,'' said Orrin Pilkey, professor of marine geology at the University of North Carolina at Chapel Hill. ``It's always give and take with nature.''
More than 20 million fish have died since June in the Tar-Pamlico and Neuse rivers, according to the state Department of Environment, Health and Natural Resources. The biggest kill - up to 10 million - began three to four weeks ago in an eight-mile stretch of the Neuse around New Bern. That kill continues.
While fish kills on the Tar-Pamlico have not been as severe, kills there this summer totaled up to 5 million dead.
Virginia, South Carolina and Georgia have similar agricultural runoff and industrial discharges but nothing like the North Carolina fish kills.
There were no pollution-related fish kills reported at all this summer in Virginia and South Carolina. In an isolated case in Georgia, a few hundred fish were killed when they were sucked into a turbine at a hydroelectric plant.
Barrier islands make up much of the coastline of the eastern United States. However, in North Carolina, the barrier islands are farther from the mainland, creating large sounds, Pilkey said.
These sounds, the Albemarle and Tar-Pamlico, empty into the Atlantic through three narrow passages, the Oregon, Hatteras and Ocracoke inlets.
``The sounds hold nutrients and pollutants in longer,'' said JoAnn Burkholder, a North Carolina State University professor who studies marine botany.
If other states had a similar geology, they would also have fish kills, she said.
``The Hudson (New York) and the Chesapeake (Maryland) have big, wide mouths,'' Burkholder said. ``If the Chesapeake was sealed up like the Pamlico, pfiesteria would love it.''
Pfiesteria is a water-borne toxin responsible for about half of North Carolina's fish kills in the last few years, researchers say. Pfiesteria and algae blooms, another major cause of kills, are heightened by the presence of pollution.
Both the Tar-Pamlico and Neuse rivers pick up industrial pollutants and runoff from farms and hog plants as they flow from the center of the state then empty into the Pamlico Sound. Instead of being diluted by the ocean, the water - choked with algae, nutrients, bacteria and chemicals - lingers in the sounds and mouths of the rivers. The Pamlico Sound totally flushes its water only once a summer.
Since large inlets cannot be carved to the ocean, the only answer is to reduce the amounts of pollutants and nutrients dumped into the state's water, said Jonathan Phillips, an East Carolina University professor who studies water and land forms.
``We will need major changes in the way we do business,'' he said. ``We have to be more careful than other states in the way we dump pollutants because of the Outer Banks. We are unique and need to realize that.''
State officials this week announced initiatives to deal with environmental problems in rivers.
Echoing what environmentalists have said for some time, state officials said that dramatic action was needed to reverse pollution problems and address health concerns.
At a meeting of the Environmental Management Commission, officials called for an accelerated plan to reduce nutrient pollution - mainly nitrogen and phosphorus - from sewage plants, agricultural runoff and other sources. ILLUSTRATION: MAJOR CAUSES OF FISH KILLS
Pfiesteria: Researchers believe this is responsible for half the
state's recent fish kills. Pfiesteria is an organism that lies
dormant on the river bottom until conditions are right, then changes
form and attacks fish. Attacks tend to occur when excessive
nutrients, mainly nitrogen and phosphorus, pour into rivers from
farms, hog plants, wastewater treatment plants and cities.
The dead fish have telltale sores on their bodies. Some people
who have come into contact with infected water have reported
dizziness, rashes and sores, prompting a state health advisory.
Algae blooms: Excessive nutrients like nitrogen and phosphate
fertilizers cause algae to grow rapidly, robbing the river of oxygen
that fish need to survive. Algae produce oxygen during the day
through a process called photosynthesis. But at night,
photosynthesis is slowed and the algae begin to eat oxygen.
Salt wedges: Freshwater rivers empty into sounds made up of sea
water. A wedge forms where the freshwater and saltwater meet because
freshwater is lighter than saltwater. A layer of debris is trapped
between the two, and bacteria forms, consuming oxygen. Fish swimming
into the area of a salt wedge suffocate.
by CNB