Too Much Nitrogen Is Bad for Bay

Nutrients--primarily nitrogen and phosphorus--are essential for the growth of all living organisms in the Chesapeake Bay. However, excessive nitrogen and phosphorus degrade the Bay's water quality.

Nitrogen pollution is the most serious pollution problem for the Bay because it causes algae blooms that consume oxygen, which lowers dissolved oxygen levels so severely that fish and shellfish die.

Over abundance of nitrogen contributes to the Bay's "Dead Zone" and creates algae blooms that block sunlight to underwater grasses and prevents their growth.

At its healthiest in the early 1600s, the Chesapeake watershed was mainly comprised of forested buffers, wetlands, and resources lands (open space and farmland) that absorbed and filtered nutrients.

Haphazard development stripped the watershed of these buffers and today pollution flows undiluted into waterways. Farms, factories, cities, and suburbs have replaced much of these natural filters. These practices have impaired the water quality so severely that the Chesapeake Bay is on the EPA's "dirty waters'' list.

CBF's health index, called the State of the Bay Report, estimates that the Chesapeake Bay watershed rated 100 on a scale of 100 in the 1600s. In 2002, CBF's State of the Bay Report again rated the Bay at 27 out of 100.

As land use patterns change and the watershed's population grows, the amount of nutrients entering the Bay's waters increases tremendously.

Each year, roughly 300 million pounds of polluting nitrogen reaches the Chesapeake Bay. Goals outlined in the new Bay agreement, called Chesapeake 2000, call for reducing nitrogen by 150 million pounds and phosphorus by 16 million pounds annually.

The combination of increasing our loadings of nutrients to the Bay and decreasing our natural buffers has resulted in the Bay being placed on the EPA's "dirty waters" list.

Major Sources of Water Pollution

Nutrients come from natural sources such as decaying organic matter in forests and wetlands.

The majority of nitrogen pollution, however, comes from human impacts, such as sewage treatment plants, large-scale animal operations, agriculture, and air pollution (mostly vehicle exhaust) and smoke stacks from industrial sources such as power plants.

Other sources include septic systems, runoff from roadways, development, residential and commercial lawn fertilizers, and air deposition from factories.

The number one source of nitrogen pollution to the Bay comes from agricultural runoff. This which contributes 40 percent of the nitrogen and 50 percent of the phosphorus entering the Chesapeake Bay.

In Maryland, manure and waste from chicken production plays a big role in agricultural nitrogen loads to the Bay. Chickens outnumber people approximately 1,000 to 1 on Maryland's Eastern Shore.

In the Shenandoah and Potomac watersheds, large-scale poultry operations produce more waste than hog, cattle, or dairy farms and up to 150 percent more of the nutrient pollution generated by human waste in the same area. In addition, poultry waste creates four times more nitrogen and 24 times more phosphorous than hog waste in Virginia.

Why Is This Bad?

Polluted runoff has "over-fertilized" Bay waters, making them eutrophic. Simply put, too much nitrogen and phosphorus are entering the watershed for the system to accomodate.

Water pollution from excess nitrogen fuels the explosive growth of algae that clouds the water and blocks out light needed by the underwater grasses.

When the algae die, they decompose and consume oxygen. Some deep channels can become so low in oxygen that they can no longer support aquatic life. This is known as the "dead zone."

Another consequence of too many nutrients in our waters is the threat of Pfiesteria piscicida, a microscopic organism that has likely existed in the Bay for thousands of years.

In 1998, a team of physicians and health experts from the University of Maryland and Johns Hopkins University medical schools determined that people heavily exposed to Pfiesteria can develop severe difficulties in learning and concentrating.

The scientists also found that people with high exposure to Pfiesteria complained of neuropsychological symptoms, including new or increased forgetfulness, headaches, and skin lesions or burning sensation when their skin comes in contact with water.

Studies indicate that Pfiesteria becomes more prevalent in part because of poor water quality associated with excessive nutrients. (NOTE: Current evidence indicates that there is no risk from eating seafood from Pfiesteria infected waters. No scientific or anecdotal evidence links the consumption of seafood to any Pfiesteria-like symptoms or any other illness.)

What Needs To Be Done?

Solutions include upgrading sewage treatment plants, proper operation of septic systems, using nitrogen removal technologies on septic systems, and decreasing fertilizer applications to lawns.

We can also reduce nutrient loads by conserving energy, which will result in fewer demands on power plants that emit nitrogen, and driving less to reduce vehicle emissions that also contribute to airborne nitrogen loads.

Important natural filters such as forests, oysters, wetlands, and underwater grasses need to be protected and restored. Maryland alone has lost more than 75 percent of its wetlands. Overall, the Bay has lost 98 percent of its oysters, about 90 percent of grasses, and nearly 50 percent of forest buffers.

To protect these natural filters and open space, it is important to support and implement local, very low-density zoning-one house per 20 acres or more. Another is local land conservation, using conservation easements or full ("fee") purchases.

To achieve the 2010 water quality goals, we must reduce the amount of nutrient runoff from agricultural sources and promote effective use of nutrient management plans, including:

Implementation of nutrient management plans;
Controlling pollution from manure;
Installing cover crops;
Installing and maintaining buffer strips along farm fields;
Setting and implementing a new riparian forest buffer goal; and
Ensuring that Conservation Reserve Enhancement Programs in each state have adequate incentives and available specified acreage to meet the 25,000-acre wetland goal and new riparian forest buffer goal.

Ten Tips for Clean and Green Boating

Prevent oily discharges from the bilge—Keep your engine well tuned to prevent fuel and oil leaks. Secure an oil absorbent pad or pillow in your bilge and under your engine where drips may occur. Check the pads often, do not let them clog the bilge pump, and use Earth911 to find out where to dispose of them.
Spill-proof your oil changes—Use an oil change pump to transfer oil to a spill-proof container. Wrap a plastic bag or absorbent pad around the oil filter to prevent oil from spilling into the bilge. Use Earth 911 to recycle your oil and filters.
Limit fuel spills—Fill your tank slowly and use absorbent pads or rags to catch drips and spills. Avoid “topping off” and leave the tank 10 percent empty to allow fuel to expand as it warms. Learn more about boat fueling.
Do not add soap—Avoid using soap to disperse fuel and oil spills. It increases harm to the environment, and it is illegal.
Minimize boat cleaning and maintenance in the water—If possible, save maintenance projects for the boatyard. When performing work on the water minimize your impact by containing waste. Learn more about boat cleaning and maintenance.
Reduce toxic discharges from bottom paints—Use a less toxic (or nontoxic antifouling) paint to minimize the discharge of heavy metals into the water. Dry storage is another good technique; it reduces the need for antifouling paints and saves money.
Dispose of hazardous waste properly—This includes paints, batteries, antifreeze, cleaning products, oil, oil filters and other hazardous wastes. Use Earth911 to find a hazardous waste collection facility or event.
Monitor dumping—Never discharge sewage within three miles of shore. Use Earth911 to find a harbor pump-out stations and shore-side facilities. Manage your sewage in general.
Stow it, don’t throw it—Keep your trash on board and out of the water. This includes cigarette butts, fishing line, or any food garbage/packaging. Take advantage of shore-side facilities to recycle plastic, glass, metal, and paper. Learn more about marine debris.
Reduce Greywater discharges—This is the soapy water resulting from boat maintenance. Try a phosphate-free biodegradable soap for your maintenance. Also minimize discharge by doing dishes and showers on shore whenever possible. See more tips for minimizing grey water.