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 a number of adverse health and ecological effects.
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Phosphorus and Water
Phosphorus is a common constituent of agricultural fertilizers, manure, and organic wastes in sewage and industrial effluent. It 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. Soil erosion is a major contributor of phosphorus to streams. Bank erosion occurring during floods can transport a lot of phosphorous from the river banks and adjacent land into a stream, lake, or other water body.

Credit: NASA
Phosphorus in surface and groundwater
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. A USGS study on Cape Cod, Massachusetts showed that phosphorus can also migrate with groundwater flows. 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.

Credit: Charles Crawford, USGS
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.
- Towns in the metropolitan Atlanta area are continuing to expand and upgrade existing wastewater-treatment facilities to handle the increasing volume of wastewater and sewage and to meet stiffer regulations on effluent and river quality.
- Additional control of phosphorus from non-point sources (such as applications of lawn fertilizers and disposal of animal wastes) may be useful to maintain or improve the water quality in streams and lakes near growing urban areas.
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. The amounts of phosphorus downstream of the city have decreased about 77% from the highest levels in 1984 because of both voluntary and mandatory restrictions on phosphorus detergents in the city. 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!
Below are other science projects associated with phosphorus and nutrients.
Excess Nutrients
Nitrogen and Water
Fate and Transport of Pathogens and Nutrients from Land-Applied Animal Manures
Below are multimedia items associated with phosphorus.
Below are publications associated with phosphorus.
Nutrients in the Nation's Waters--Too Much of a Good Thing?
Temporal changes in nitrogen and phosphorus concentrations with comparisons to conservation practices and agricultural activities in the Lower Grand River, Missouri and Iowa, and selected watersheds, 1969–2015
The quality of our nation's waters: Nutrients and pesticides
Below are data or web applications associated with phosphorus.
GLRI Edge-of-Field Monitoring (geonarrative)
The GLRI Edge-of-Field Monitoring project focuses on identifying and reducing agricultural sources of excess nutrients which can threaten the health of the Great Lakes. This geonarrative details the basics of edge-of-field monitoring (EOF), explores EOF applications, shows USGS is working collaboratively with our partners, and discusses how EOF can improve conservation efforts.
Below are news stories associated with phosphorus.
New Study Quantifies Benefits of Agricultural Conservation in Upper Mississippi River Basin
USGS-USDA Modeling Research Show Up to 34% Reduction in Nitrogen from Agricultural Conservation Practices
- Overview
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 a number of adverse health and ecological effects.
• Water Science School HOME • Water Properties topics • Water Quality topics •
Phosphorus and Water
Phosphorus is a common constituent of agricultural fertilizers, manure, and organic wastes in sewage and industrial effluent. It 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. Soil erosion is a major contributor of phosphorus to streams. Bank erosion occurring during floods can transport a lot of phosphorous from the river banks and adjacent land into a stream, lake, or other water body.
Sources/Usage: Public Domain. Visit Media to see details.Toxic Algal Bloom, Lake Eire, 2011. The green scum shown in this image is the worst algal bloom Lake Erie has experienced in decades. Such blooms were common in the lake’s shallow western basin in the 1950s and 60s. Phosphorus from farms, sewage, and industry fertilized the waters so that huge algae blooms developed year after year. In 2011, heavy snow fell in the winter and spring, resulting in snowmelt runoff, followed by heavy rainfall in April. The rain and melting snow ran off fields, yards, and paved surfaces, carrying an array of pollutants into streams and rivers—including phosphorus and nitrogen from fertilizers. More rain and runoff resulted in more phosphorus that nutrient nourished the algae in the lake. Though not directly toxic to fish, the bloom isn’t good for marine life. After the algae dies, bacteria break it down. The decay process consumes oxygen, so the decay of a large bloom can leave "dead zones” - low oxygen areas where fish can’t survive. If ingested, the algae can cause flu-like symptoms in people and death in pets.
Credit: NASAPhosphorus in surface and groundwater
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. A USGS study on Cape Cod, Massachusetts showed that phosphorus can also migrate with groundwater flows. 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.
Sources/Usage: Public Domain. Visit Media to see details.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.
Credit: Charles Crawford, USGSPhosphorus 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.
- Towns in the metropolitan Atlanta area are continuing to expand and upgrade existing wastewater-treatment facilities to handle the increasing volume of wastewater and sewage and to meet stiffer regulations on effluent and river quality.
- Additional control of phosphorus from non-point sources (such as applications of lawn fertilizers and disposal of animal wastes) may be useful to maintain or improve the water quality in streams and lakes near growing urban areas.
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. The amounts of phosphorus downstream of the city have decreased about 77% from the highest levels in 1984 because of both voluntary and mandatory restrictions on phosphorus detergents in the city. 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!
- Science
Below are other science projects associated with phosphorus and nutrients.
Excess Nutrients
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.Nitrogen and Water
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.Fate and Transport of Pathogens and Nutrients from Land-Applied Animal Manures
This collaborative project between the U.S. Environmental Protection Agency (USEPA) and the USGS was conducted as part of a larger research program being undertaken by USEPA and the U.S Department of Agriculture at several research sites throughout the United States. Goals included: 1. Obtain detailed data concerning the survival of pathogenic microorganisms from manure applied to soil under... - Multimedia
Below are multimedia items associated with phosphorus.
- Publications
Below are publications associated with phosphorus.
Nutrients in the Nation's Waters--Too Much of a Good Thing?
Historical data on nutrients (nitrogen and phosphorus) from about 12,000 ground-water and more than 22,000 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 percentages should not be taken as those for the Nation aAuthorsDavid K. Mueller, Dennis R. HelselTemporal changes in nitrogen and phosphorus concentrations with comparisons to conservation practices and agricultural activities in the Lower Grand River, Missouri and Iowa, and selected watersheds, 1969–2015
This report presents the results of a cooperative study by the U.S. Geological Survey and Missouri Department of Natural Resources to estimate total nitrogen (TN) and total phosphorus (TP) concentrations at monitoring sites within and near the Lower Grand River hydrological unit. The primary objectives of the study were to quantify temporal changes in TN and TP concentrations and compare those conAuthorsHeather M. Krempa, Allison K. FlickingerThe quality of our nation's waters: Nutrients and pesticides
This report is the first in a series of nontechnical publications, 'The quality of our nation's waters,' designed to describe major findings of the National Water-Quality Assessment Program regarding water-quality issues of regional and national concern. Sources, seasonal and geographic patterns of occurrence, and long-term trends are evaluated for nutrients and pesticides in streams and ground waAuthors - Web Tools
Below are data or web applications associated with phosphorus.
GLRI Edge-of-Field Monitoring (geonarrative)
The GLRI Edge-of-Field Monitoring project focuses on identifying and reducing agricultural sources of excess nutrients which can threaten the health of the Great Lakes. This geonarrative details the basics of edge-of-field monitoring (EOF), explores EOF applications, shows USGS is working collaboratively with our partners, and discusses how EOF can improve conservation efforts.
- News
Below are news stories associated with phosphorus.
New Study Quantifies Benefits of Agricultural Conservation in Upper Mississippi River Basin
USGS-USDA Modeling Research Show Up to 34% Reduction in Nitrogen from Agricultural Conservation Practices