Phosphorus: A Double-Edged Sword In Our Environment

Phosphorus is an essential nutrient for plant growth, but it can become a pollutant when it enters waterbodies in excess. This can occur through nonpoint source pollution, such as urban stormwater runoff, which carries phosphorus from fertiliser, pet waste, and lawn clippings into storm drains. When additional phosphorus becomes available to aquatic systems, it stimulates the growth of algae and other aquatic plants, leading to a condition called eutrophication. Eutrophication results in an overproduction of organic matter, blocking sunlight and killing native bottom-dwelling plants. As the plants decay, they use up oxygen in the water, leading to hypoxia, which makes it difficult for aquatic animals to survive.

Phosphorus is not a groundwater pollutant, but it can be a pollutant in aquatic ecosystems

When additional phosphorus becomes available to aquatic systems, it stimulates the growth of algae and other aquatic plants. This condition of nutrient enrichment and high plant productivity is referred to as eutrophication. Eutrophication results in an overproduction of organic matter, particularly algae. The excess algae block the sunlight needed by native bottom-dwelling plants, often killing them. As the algae and bottom-dwelling plants die, they decay, using up oxygen in the water. This leads to hypoxia, which makes it difficult for aquatic animals like fish and crabs to survive.

Urban areas may produce significant nonpoint source phosphorus runoff due to the over-application of fertiliser to lawns and gardens. Homeowners who apply fertiliser without a soil test can build up very high soil test phosphorus levels that can become significant sources of phosphorus in runoff. Fertiliser, pet waste and lawn clippings left on driveways, sidewalks or streets are a direct source of pollution through storm drains in urban areas. Grass clippings on streets can be washed into water bodies and become a nutrient source.

Phosphorus is an essential nutrient for plant growth, but too much can lead to eutrophication

Phosphorus is typically not considered a groundwater pollutant, as most soils have the capacity to retain phosphorus in their upper layers, protecting the groundwater. However, excess phosphorus is a concern for most aquatic ecosystems. Under background conditions, where human activities do not dominate the landscape, phosphorus is generally in short supply. Its absence limits the growth of algae and aquatic plants.

When additional phosphorus becomes available to the aquatic system, it stimulates the growth of algae and other aquatic plants. This condition of nutrient enrichment and high plant productivity is referred to as eutrophication. Under eutrophic conditions, the recreational values of lakes and streams may suffer. Eutrophication results in an overproduction of organic matter, particularly the microscopic plants called algae. You may have seen green masses of algae growing on a pond or lake. This excess algae blocks the sunlight needed by native bottom-dwelling plants, often killing them.

Urban areas may produce significant nonpoint source phosphorus runoff due to the over-application of fertiliser to lawns and gardens. Homeowners who apply fertiliser without a soil test eventually build up very high soil test phosphorus levels that can become significant sources of phosphorus in runoff. Fertiliser, pet waste and lawn clippings left on driveways, sidewalks or streets are a direct source of pollution through storm drains in urban areas.

Fertilizer on sidewalks and driveways is a non-point source of phosphorus pollution

Phosphorus is typically not considered a groundwater pollutant because most soils have the capacity to retain phosphorus in the upper layers, protecting the groundwater. However, urban areas may produce significant non-point source phosphorus runoff due to over-application of fertilizer to lawns and gardens. Homeowners who apply fertilizer without a soil test can eventually build up very high soil test phosphorus levels that can become significant sources of phosphorus in runoff. In addition to fertilizer, pet waste and lawn clippings left on driveways, sidewalks or streets are also direct sources of phosphorus pollution through storm drains in urban areas.

Factors that affect the level of non-point source phosphorus in runoff from cropland and pasture land include soil phosphorus concentration, or Soil Test Phosphorus (STP), the erosion rate and the application rate and timing of commercial fertilizer, composts or animal manure. Grass clippings on streets can be washed into water bodies and become a nutrient source for algae. To reduce the impact of phosphorus pollution on aquatic ecosystems, it is important to properly manage the application of fertilizer and to dispose of pet waste and lawn clippings in a way that does not contribute to runoff.

Urban areas produce significant nonpoint source phosphorus runoff due to over-application of fertilizer

Phosphorus is not usually considered a groundwater pollutant, as most soils have the capacity to retain phosphorus in their upper layers, protecting the groundwater. However, phosphorus is a concern for aquatic ecosystems, as excess phosphorus can lead to eutrophication. This is a condition of nutrient enrichment and high plant productivity, which results in an overproduction of organic matter, particularly algae.

Urban areas produce significant nonpoint source phosphorus runoff due to the over-application of fertiliser to lawns and gardens. Homeowners who apply fertiliser without a soil test can build up very high soil test phosphorus levels, which can become a significant source of phosphorus in runoff. Fertiliser, pet waste and lawn clippings left on driveways, sidewalks or streets are a direct source of pollution through storm drains in urban areas.

Factors that affect the level of nonpoint source phosphorus in runoff from cropland and pasture land include soil phosphorus concentration, or Soil Test Phosphorus (STP), the erosion rate and the application rate and timing of commercial fertiliser, composts or animal manure. Grass clippings on streets can be washed into water bodies and become a nutrient source.

Point sources of phosphorus, such as municipal and industrial waste treatment plants, are generally governed by federal and state regulations and permits. Urban and industrial stormwater and the storm sewer systems of larger cities are also regulated by federal and state permits.

Phosphorus in storm drains is a direct source of pollution

Phosphorus is not typically considered a groundwater pollutant, as most soils have the capacity to retain phosphorus in their upper layers, protecting the groundwater. However, when phosphorus does enter aquatic ecosystems, it can cause eutrophication. This is a condition of nutrient enrichment and high plant productivity, which results in an overproduction of organic matter, particularly algae. The excess algae blocks the sunlight needed by native bottom-dwelling plants, often killing them. As the algae and bottom-dwelling plants die, they decay, using up oxygen in the water. This leads to hypoxia, which makes it difficult for aquatic animals like fish and crabs to survive.

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