One major issue with lakes across the United States is excess phosphorus runoff and contamination. A study performed by Kansas State University showed that over 90% of US lakes across the country have excess amounts of phosphorus (Dodds, 2008, 1). Phosphorus is an important nutrient in the growth of plants and thus is needed by all plants to maintain health and proper growth. Unfortunately, water regions throughout the United States face excess phosphorus contamination and thus see excess growth. Phosphorus stimulates growth and when too much phosphorus is present, plants and algae grow too quickly and thickly to support the rest of the water ecosystem. These excess plants then consume too much oxygen and sunlight to support the rest of the ecosystem thus causing other organisms to be chocked out (Phosphorus on, N.D.,1). Eutrophication, as this process is termed, causes the water
quality of these waterways to diminish and also cause external costs to consumers of the water. Most people are aware of the process eutrophication, but are unaware of its effects on water quality as a whole and thus the quality of consumer water. This phenomenon is present in one of Vermont’s most prominent lakes, Lake Champlain.
Like most US lakes, Lake Champlain faces excess phosphorus runoff causing many of these water quality problems. Phosphorus enters the lake from two main sources, point and nonpoint sources. It is estimated that in Vermont point source pollution accounts for 10% of phosphorus runoff, while nonpoint sources account for 90%. This is because a nonpoint source is one which is unidentified and thus harder to control (Phosphorus pollution, 2009, 1). The Lake
Champlain Basin Program has put much effort into reducing point source pollution and this is evident in how most phosphorus pollution comes from nonpoint sources. Studies by the Lake Champlain Land Trust have also determined that 46% of nonpoint phosphorus runoff comes from urban areas, whereas 36% comes from agricultural sectors (Phosphorus pollution, 2009, 1). In addition, a 2007 report from the Lake Champlain Basin Program determined that “On an acre per acre basis, developed land contributes about 3.5 times as much phosphorus to the Lake as agricultural land (Phosphorus on, N.D.,1)”. From this information, it can be easily seen that water quality problems arise mainly from improper management of phosphorus in urban areas and not just the agricultural sectors. The excess phosphorus that enters Lake Champlain comes from a variety of sources including lawn fertilizers, human waste, animal waste, manure, and even improper wastewater treatment (Phosphorus pollution, 2009, 1). Patrick Philips, a member of U.S. Geological Survey found that Burlington also faces improper sewer systems that frequently become overfilled. When these drainage systems become overfilled they transmit raw sewage and untreated runoff into water sources that ultimately reach Lake Champlain (Philips, 2009,1). These chemicals and byproducts are on the grounds and then eventually get carried into by water runoff when it rains or snows, eventually entering Lake Champlain. It is obvious to see that these items greatly decrease the water quality of the lake and make tasks like water treatment a difficult. Treating a lake that contains manure, human feces, and chemical fertilizers is a much harder task than treating a lake where these items are minimized on a daily basis.
One final major water quality problem associated with this excess water runoff has to do with the formation of algal
blooms. A major problem with Lake Champlain is elevated levels of blue-green algae created by the phosphorus levels in the lake. There are two main problems associated with algal blooms. The first obvious problem associated with these organisms is that they take up large portions of the lake and thus are a main choking agent for other organisms. Blue-green algae spread very quickly and thus lower water quality simply by their presence across the lake. This makes water treatment and water quality diminish because of the inability to find regions of the lake that are pure sources. The second, and less obvious, reason these algal blooms are bad for Lake Champlain is because of their ability to produce harmful toxins. Most of the time blue-green algae are harmless, but blue-green algae have the ability to produce harmful neurotoxins that if ingested in large quantities can be extremely dangerous (Blue-green, 2009, 1). The toxins that this algae produce can be very harmful and between 1999 and 2000 three dogs died simply from drinking water straight from Lake Champlain and ingesting the toxins (Blue-green, 2009, 1). From this it can be seen that excessive phosphorus runoff causes increased water quality problems from algal blooms. As a result, larger efforts have to be taken to both find pure water sources and treat the non-pure sources. Treatment facilities must put extra effort especially into making sure the harmful toxins produced by these algal blooms are not in the water because of their ability to cause serious health problems and even death. Excess phosphorus levels cause many water quality problems and thus solutions must be taken to reduce these levels.
The Lake Champlain Basin is putting much effort into reducing phosphorus levels across Vermont, New York, and Canada. One approach that is being taken is increasing best management practices (Phosphorus on, N.D.,1). This includes practices such as decreasing nutrient and waste runoff by storing manure in pits for example. Also new laws have been created about when farmer’s fields can be fertilized with manure. Another BMP includes creating a plant border around farmer’s fields that absorb excess phosphorus before it enters the lake (Phosphorus on, N.D.,1). In addition to BMPs, in 2002 Vermont and Quebec signed the Missisquoi Bay Phosphorus Reduction Agreement which promised to reduce 98 metric tons of phosphorus runoff per year (Phosphorus on, N.D.,1). Finally the Lake Champlain Basin Program has been working with many partners since 2006 to encourage homeowners to use non-phosphorus fertilizers (Phosphorus pollution, 2009, 1). There are many things being done around the Lake Champlain Basin to reduce the phosphorus levels in the lake and thus maintain the water quality of the lake.