Phosphorus is an essential nutrient in a plant or animal’s growth. The plants and organisms that live in Lake Champlain therefore require it for their development. Phosphorus causes a problem when more phosphorus enters the water than the plants and organisms need, disturbing the delicate nutrient balance that exists. Phosphorus stimulates growth, so when too much of it ends up in the lake some plants and algae grow too quickly and thickly. This overgrowth of plant matter absorbs too much oxygen and sunlight that is needed by fish and plants below the surface waters. Additionally the ultimate decomposition or these plants creates a toxic environment for other organisms. As a result the Lake’s normal ecosystem is dramatically altered (Lake Champlain Basin Program, n.d.).
Research suggests that just one pound of phosphorus can feed 300-500 pounds of algae in a water body. While most algae blooms are generally harmless to humans, decomposing algae and weeds take up oxygen in the water that is vital to fish and other animals. Algae and weeds also discourage swimmers, anglers, and boaters—and even lower property values. Phosphorus also feeds and is absorbed by toxic blooms of blue-green algae, a bacteria called cyanobacteria that are occasionally found in the parts of Lake Champlain. In recent summers, cyanobacteria blooms have caused beach closings and health alerts in parts of northern Lake Champlain (LCC: Phosphorus Pollution in Lake Champlain, n.d).
In hot, dry weather, blue-green algae can become toxic – contributing to frequent and in some cases permanent beach closings. A health advisory was issued on August 3, 2001, warning Vermonters to keep children and pets out of the Lake. During the summer of 1999, three dogs that entered the water died from exposure to toxic blue-green algae. The Vermont Health Department continues to post advisories that often report the risks of toxic blue-green algae in Missisquoi Bay and St. Alban’s Bay (“Conservation Law Foundation :: Our Work :: Clean Water & Healthy Forests :: Great Waters :: Lake Champlain,” 2009). Lake Champlain’s beaches are closed with increasing regularity to protect human and animal health. Two, in fact, have closed permanently: Blanchard Beach in Burlington, VT and Essex Beach in NY. Both permanent and temporary beach closings are caused by water-related pathogens and deadly toxic algae blooms (Other beaches mapped here). Pathogens include giardia, swimmer’s itch and cryptosporidium.
There have been many efforts to remove phosphorus from the lake. A clean up plan was developed in 2002 and since then over $100 million dollars have been spent on phosphorus removal.
“The Lake Champlain Phosphorus TMDL was developed and submitted jointly by the States of Vermont and New York to the U.S. Environmental Protection Agency in 2002, following an extensive public participation process in each state. The TMDL built upon a sequence of studies, plans, and agreements completed during the preceding twelve years. A subsequent water quality agreement between Vermont and Quebec was signed in 2002 to define phosphorus load reduction targets and responsibilities for the shared Missisquoi Bay portion of the lake. The 2002 TMDL included a Vermont-specific implementation plan describing a suite of action items and attendant funding needs to reduce the phosphorus load delivered annually to Lake Champlain. The implementation plan has served as a basis for the efforts of the state agencies of Natural Resources and Agriculture, Food and Markets by guiding annual funding requests, staffing levels, and program priorities for the past seven years.” (Vermont Legislature, 2010)
On August 26th, 2002 Vermont and Quebec signed the Missisquoi Bay Phosphorus Reduction Agreement. This agreement pledged to reduce approximately 98 metric tons of phosphorus per year, 60% in Vermont and 40% in Quebec. This will be done through such measures as upgrading our wastewater treatment plants, best management practices, stabilization of stream banks and channels, improving storm water management, and controlling erosion. Prior to the agreement, the Lake Champlain Basin Program succeeded in reducing phosphorus loads by about 38.8 metric tons per year in 2001, exceeding their goal (“Phosphorus,” n.d.).
There are also many things individuals can do to reduce phosphorus in the lake.
- Reduce or discontinue use of pesticides.
- Use phosphate free dishwashing and laundry detergents.
- Clean up after your pets so that the waste does not run off directly into the lake untreated.
- Wash your car on grass rather than pavement so the detergent can be filtered through the grass instead of running directly into the storm water system and into the lake untreated.
- If you have a lawn, cut back on the amount of fertilizer you use. Cut only a third of the length of the grass with a sharp blade, leaving the cuttings to naturally fertilize the grass. If you fertilize, use a low phosphate fertilizer.
- If you live near or on the Lake, landscape your property with native plants that will provide a buffer between your lawn, garden, or road so as to filter out any pollutants including phosphorus before they reach the Lake. Roots are great filters. They also keep soil (which phosphorus likes to cling onto) in place.
Conservation Law Foundation :: Our Work :: Clean Water & Healthy Forests :: Great Waters :: Lake Champlain. (2009). Retrieved May 02, 2010, from http://www.clf.org/work/CWHF/lakechamplain/index.html
Harsha, K. (2010, April 29). Lake Champlain cleanup plan in trouble? – WCAX.COM Local Vermont News, Weather and Sports. Retrieved May 02, 2010, from http://www.wcax.com/Global/story.asp?S=12400364
Lake Champlain Basin Program. (n.d.). Lake Champlain Basin Program: Phosphorus Pollution. Retrieved April 8, 2010, from http://www.lcbp.org/PHOSPSUM.htm
Phosphorus. (n.d.). Retrieved May 02, 2010, from http://www.lclt.org/index.php?option=com_content&view=article&id=42&Itemid=33
Vermont Legislature (Rep.). (2010, January 15). Retrieved May 2, 2010, from Vermont Agency of Natural Resources website: http://www.leg.state.vt.us/reports/2010ExternalReports/252919.pdf