Airborne Contaminants Significantly Affect New England's Waterways

A recently released study led by the U.S. Geological Survey (USGS) shows that nitrogen entering the atmosphere from various sources has a major effect on the quality of streams throughout New England. Using a new computer model designed to map nitrogen and phosphorus transport and how these natural elements change stream quality, scientists determined that 50 percent of the nitrogen found in New England streams, or more than 42,000 metric tons per year, comes from the atmosphere. This nitrogen originates both inside and outside the region.

“Nitrogen is an element released into the atmosphere from numerous sources, including fossil fuel combustion, agricultural fertilizers, and animal manure. Wastewater facilities and various urban and suburban land uses also contribute to the amount of nitrogen in the region's streams,” said Richard Moore, USGS Hydrologist and chief investigator of the study. Although nitrogen is a necessary nutrient for plants and animals, too much nitrogen in water can lead to excessive plant growth in streams, lakes, and coastal waters; fish kills; and rivers that are unsuitable for recreation and other uses.

The New England Interstate Water Pollution Control Commission (NEIWPCC) and the U.S. Environmental Protection Agency (USEPA) collaborated in the study to better understand and manage nutrient contamination and to improve the water quality in New England's rivers.

“We were surprised to find that contrary to previous theories, nitrogen, once it enters the water, stays dissolved in the larger streams and rivers in New England all the way to the coast where the river discharges into the ocean,” said Moore. “The new computer model we developed now allows us to better identify the major sources of nutrients to New England's rivers, where they come from, and how the quality of the rivers is affected.”

"As we approach the 34th anniversary of Earth Day, USEPA is continuing to improve our ability to assess the health of New England's rivers and streams and our understanding of what is needed to restore them," said Robert W. Varney, regional administrator of USEPA's New England Office. "With this new tool, state and local agencies interested in protecting their local water bodies have access to important data to achieve those goals."

Already scientists are using the computer models to determine how pollutants entering the Connecticut River Watershed affect the health of Long Island Sound.

"Long Island Sound is one of our region's most important and valuable estuaries. Improving the quality of the Sound is a critical goal for all environmental agencies in the Sound's watershed. Currently, we are working on a long-term plan to reduce the amount of nitrogen that enters the Sound using some of the information generated by this study in combination with other studies," said Ronald Poltak, Executive Director of the New England Interstate Water Pollution Control Commission.

The USEPA and states in New England will use the new contaminant-tracking tool to determine what level of nitrogen and phosphorus adversely affects the health of streams and to define acceptable levels of these contaminants in rivers and streams.

These findings are released as USGS Scientific Investigations Report 2004-5012, “Estimation of total nitrogen and phosphorus in New England streams using spatially referenced regression models,” by R.B. Moore and others, which is available online at http://pubs.water.usgs.gov/sir2004-5012 or by contacting the USGS office in Pembroke, N.H. at (603) 226-7837.

The USGS serves the nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life.

To receive USGS news releases go to www.usgs.gov/public/list_server.html to subscribe.

Return to the NH/VT Water Science Center News Page

Return to the NH/VT Water Science Center Home Page