More rain and runoff resulted in more phosphorus that nutrient nourished the algae in the lake. After the algae dies, bacteria break it down. If ingested, the algae can cause flu-like symptoms in people and death in pets. Phosphorus gets into water in both urban and agricultural settings. Phosphorus tends to attach to soil particles and, thus, moves into surface-water bodies from runoff. Since groundwater often discharges into surface water, such as through streambanks into rivers, there is a concern about phosphorus concentrations in groundwater affecting the water quality of surface water.
Phosphorus and other nutrients can enter urban streams via urban runoff during rainfall events. Here an urban sewer overflow, due to heavy rains, is causing runoff likely containing phosphorus, nitrogen, ammonia, nitrates, and raw sewage into Fall Creek, Indianapolis, Indiana. Phosphorus is an essential element for plant life, but when there is too much of it in water, it can speed up eutrophication a reduction in dissolved oxygen in water bodies caused by an increase of mineral and organic nutrients of rivers and lakes.
This has been a very serious problem in the Atlanta, Georgia, area, as a major lake that receives Atlanta's waste water, West Point Lake, is south of the city. In metropolitan Atlanta, phosphorus coming into streams from point sources, primarily wastewater-treatment facilities , have caused West Point Lake to become highly eutrophic "enriched". A sign of this is excess algae in the lake. State laws to reduce phosphorus coming from wastewater-treatment facilities and to restrict the use of phosphorus detergents has caused large reductions in the amounts of phosphorus in the Chattahoochee River south of Atlanta, Georgia and in West Point Lake.
The first chart below shows the amount of phosphorus, in tons per year, upstream and downstream of the Chattahoochee River at Atlanta, which is a major source of the local water supply. As the bottom line shows, though, the total phosphorus load in the more agricultural area north of town continues to increase.
The chart below shows both the wastewater discharge and the amount of phosphorus discharged from Atlanta's wastewater-treatment plants. It makes sense that the total amount of wastewater would be going up as population increases, but the tonnage of phosphorus has been greatly reduced both by improvements in the treatment process and by restrictions on phosphate detergents.
Want to know more about phosphorus and water? Follow me to the Nutrients and Eutrophication website! USGS scientists have gained a better understanding of the nutrient supply and how nutrients affect habitat quality, algal productivity, and food-web dynamics in the Bay-Delta.
Nutrients, such as nitrogen and phosphorus, are essential for plant and animal growth and nourishment, but the overabundance of certain nutrients in water can cause several adverse health and ecological effects. This collaborative project between the U.
S Department of Agriculture at several research sites throughout the United States. Goals included:. Obtain detailed data concerning the survival of pathogenic microorganisms from manure applied to soil Historical data on nutrients nitrogen and phosphorus from about 12, ground-water and more than 22, stream samples have been compiled and related to possible sources.
This existing information was collected by many agencies for a variety of purposes. Therefore, though it can be used to determine where concentrations differ, the exact Manure Cow and other animal manure can leak nutrients, like phosphorus, into soil.
Precipitation can carry phosphate nutrients from the original location down into the nearest body of water. Fertilizer Farms and croplands near bodies of water are often a significant risk factor. During a rainstorm, runoff can carry phosphates found in farming soil and drain them into the nearest lake or pond.
Sewage Human waste carries high levels of phosphates. When treatment plants and other industrial areas produce or try to treat waste, the remaining nutrients may easily leach into surrounding soil and, eventually, water.
The Effects of Phosphate Pollution These are the most common and most dangerous effects of high phosphate levels in water. Why monitor phosphate levels in water? Why do phosphates cause a problem? Algal blooms can cause problems as they: Disrupt the normal functioning of an ecosystem; Deplete dissolved oxygen levels; May block out sunlight preventing other photosynthetic organisms to survive; Can produce toxins which are harmful to higher trophic levels and cause problems further along in the food chain; Cause a risk to human health from threat near to drinking water intakes; Decrease the aesthetic appearance of water bodies.
Where does the excess phosphorous come from? Site Investigations. Please enable JavaScript in your browser to complete this form. Subscribe now. Home Products Services Case Studies. This aging process can result in large fluctuations in the lake water quality and trophic status and in some cases periodic blooms of cyanobacteria.
In situations where eutrophication occurs, the natural cycles become overwhelmed by an excess of one or more of the following: nutrients such as nitrates, phosphates, or organic waste containing these nutrients.
The excessive inputs, usually a result of human activity and development, appear to cause an imbalance in the "production versus consumption" of living material biomass in an ecosystem. This overproduction can lead to a variety of problems ranging from anoxic waters the decomposition of the excess organic matter in the water greatly lowers the dissolved oxygen content of the water to toxic algal blooms, adecrease in diversity andfood supply, and habitat destruction.
Eutrophication as a water quality issue has had a high profile since the late s, following the widespread occurrence of blue-green algal blooms in some fresh waters.
Some blue-green algae can at times produce toxins, which are harmful to humans, pets, and farm animals. At this time, the water plants and algae begin to grow more rapidly than normal.
As this happens there is also an excess die-off of the plants and algae as sunlight is blocked at lower levels. Bacteria try to decompose the organic waste, consuming the oxygen, and releasing more orthophosphate which is known as "recycling or internal cycling. In anaerobic conditions absence of oxygen , conditions worsen as more phosphates and nitrates are added to the water; all of the oxygen may be used up by bacteria in trying to decompose all of the waste.
Different bacteria continue to carry on decomposition reactions, however, the products are drastically different. The carbon is converted to methane gas instead of carbon dioxide and sulfur is converted to hydrogen sulfide gas. Some of the sulfide may be precipitated as insoluble iron sulfide pyrite.
Under anaerobic conditions, the iron phosphate precipitates in the sediments may be released from the sediments, making the phosphate bioavailable.
This is a key component of the growth and decay cycle. The pond, stream, or lake may gradually fill with decaying and partially decomposed plant materials to make a swamp, which is the natural aging process. The problem is that this process has been significantly accelerated. Point sources may include wastewater treatment plants and permitted industrial discharges. In general, non-point source pollution typically is significantly higher than point-sources of pollution.
Therefore, the key to sound management is to limit the input from both point- and nonpoint-sources of phosphate. Plants may not be able to utilize all of the phosphate fertilizer applied.
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