Total Phosphates

Phosphorus is an element that is necessary for plant and animal growth. Animals use phosphorus bone growth as well as for reactions within the body allowing it function. Plants use phosphorus in order to grow, which provides food for fish.
Phosphates can be found in several forms. Orthophosphates, which are found in wastewater, are produced naturally. Polyphosphates are used for the production of laundry detergents as well as for treating water boilers. Organic phosphates are produced by living organisms and the breakdown of organic pesticides.

Testing for Total Phosphates

One way of testing for total phosphates is by testing the color change of a water sample. In order to do so, a water sample is taken. A powder is then added to the sample. If the sample changes to a blue-violet color, it can be inferred that there is phosphate present. The color is then compared to a scale in order to figure the amount of total phosphates.

Total Phosphate Levels and What They Mean

Amount of Total Phosphates	Significance/Meaning
0.01-0.03 (mg/L)	Water is uncontaminated
0.025 (mg/L)	Increases rate of eutrophication
0.1 (mg/L)	Maximum for rivers and streams

Results

The results of the amount of total phosphates found in the North Channel of the Chicago River are listed below:

Site	Amount of Total Phosphates
1	0 (mg/L)
2	3 (mg/L)
3	5 (mg/L)

The average of these results exceeds the maximum acceptable amount of total phosphates by far. These large amounts of phosphate cause plants to grow at an exceedingly fast rate, a process called eutrophication. This may produce an algae bloom, which are thick layers of green slime that cover the surface of water. These algae blooms are harmful to organism living within the water because they decrease the dissolved oxygen level by preventing air from contacting the water. They also increase the amount of heat going into the water because of their heat absorbent characteristics. This furthers the decrease of dissolved oxygen. Algae blooms also decrease the amount of sunlight that reaches plants in the water, causing them to die. This then kills off many other organisms living in the water.

Influences

The amount of total phosphates is influenced by human or animal wastes, fertilizers, pesticides, industry, soaps, and the disturbance of land. Humans have much of an influence on the amount of total phosphates that flow into rivers from agricultural runoff, sewage, detergents, and more. Algae blooms are caused by cultural eutrophication, which is human-caused eutrophication. As shown earlier, algae blooms are a result of a large amount of phosphates added into water. This can greatly disturb aquatic life by killing many plants and other organisms living in the water.
We can reduce the amount of phosphates going in to the water, by cutting down on the amount of fertilizers we use especially in agriculture and lawns.