Phosphorus exists as phosphate (PO4) when in water. The phosphate is a requirement in aquatic life. It stimulates the growth of plants such as planktons in waterways which provide food for the fish. The increment in fish population improves the overall water quality (Oram). However, excess phosphates are detrimental to the waterways. They cause algae and other aquatic plants to grow wildly and cause eutrophication or the choking up of waterways. Eutrophication is detrimental to aquatic life. As the plants die and decompose, they use up massive amounts of oxygen diminishing the oxygen levels in the water. Low levels of dissolved oxygen cause the deaths of aquatic plants and animals (Kotoski 2). Dead plant matter eventually builds up and sediments at the base of the waterway making it shallow.
Algal matter and decaying aquatic plants produce odors and discolors water which interferes with the aesthetic and recreational uses of waterways. Excessive amounts of phosphates in waterways can also cause problems in water treatment. Water containing phosphates levels greater than 1.0 interferes with the coagulation process in water treatment plants (Oram). Consequently, organic particles harboring microorganisms may not be thoroughly removed before the water is distributed.
I’ll be testing water from Gompers Park wetlands near the Chicago Rivers. The total phosphate test measures the immediate and the potentially available forms of phosphorus in the sample. The filterable reactive phosphate test uses ascorbic acid to test for the presence of phosphates. When present, the acid turns blue. Filtering the sample prior to testing measures only dissolved orthophosphate (Kotoski 3). To test all forms of phosphorus present, the sample is mixed with suitable reagents prior to testing. Color comparators- a spectrum with different shades of blue-are used to monitor the sites with high phosphate concentration (more than 0.1mg/l) from different waterways such as run-off in urban streams, storm-water and wastewater treatment outfalls.
Works cited
Kotoski, James. Black Earth Creek & Limnology Minifacts & Analysis: Sheet 2: Phosphorus
Amounts-Information on Phosphorus Amounts & Water Quality. Spring Harbor
Environmental Magnet Middle School. 1997
Oram, Brian. Water Research Center. Phosphates in the Environment. What are phosphates?
B.F. Environmental Consultants Inc. Web. April 11 2012. http://www.water-
research.net/Watershed/phosphates.htm
