Nutrient Pollution


Nutrient pollution is caused by an excess of nutrients, primarily nitrogen and phosphorus, in air and water. While nitrogen and phosphorus are important components of a healthy ecosystem, there can be “too much of a good thing”. An overabundance of nutrients can lead to a number of negative environmental effects, including detrimental health impacts (nausea, vomiting, skin rashes, etc.) and harmful algal blooms (HABs).

Harmful Algal Blooms (HABs)lake_algae_t440

Algal blooms are the result of excess nutrients in water and can harm food resources and habitats. They decrease the oxygen in water that is necessary for aquatic life to survive, which can lead to fish kills and illness. Algal blooms can also be harmful to humans as some algal blooms produce elevated toxins and bacterial growth, which can lead to illness when people come into contact with or drink polluted water or consume contaminated fish or shellfish.


There are many causes of nutrient pollution, most of which are human induced.

  • Agriculture – fertilizer, manure, and soil erosion all can lead to pollution of waters by runoff
  • Stormwater – runoff from urban areas such as roads, sidewalks, and rooftops
  • Wastewater – sewer and septic systems
  • Fossil fuels – increase nitrogen in the air via generation of electric power, transportation, industry and agriculture
  • Homeowners – yard fertilizers, pet and yard waste, the use of detergents and soaps that contain nitrogen and phosphorus


Human Health Effects

  • Drinking water in agricultural areas can often be contaminated by nitrates, which can lead to blue baby syndrome when infants consume it.
  • Drinking, accidentally ingesting, or swimming in water during a HAB can cause respiratory problems, rashes, stomach or liver illness, and neurological affects.
  • Disinfectants that are used to treat drinking water can react with toxic algae and form dioxins, which are harmful chemicals that have been linked to reproductive and developmental health risks, including cancer.

Environmental Effects

  • Direct exposire to algae can lead to:dead_fish0834
    • Fish kills
    • Harm to larger animals by moving up the food chain
    • Clogged gills in fish
  • Dead zones and hypoxia
    • Algae blooms consume oxygen and can create dead zones, devoid of, or seriously lacking, available oxygen. Benthic organisms – those that live on the seafloor – and young fish are among those most likely to die as a result of hypoxia.
    • There are over 166 dead zones across the nation, including those in the Gulf of Mexico and Chesapeake Bay.
  • Acid rain
    • Damages lakes, streams, estuaries, forests, and grasslands
  • Air pollution
    • Excess nitrogen can lead to the formation of other pollutants such as ground-level ozone, which can damage vegetation and lead to smog.

Economic Effects

  • Drinking water costsalgebloom.jpg
    • The cost of treatment
    • Clean up of polluted water bodies
  • Tourism losses
    • Fishing and boating activities are limited as a result of nutrient pollution and HABs, resulting in close to $1 billion per year in tourism industry losses.
    • Airborne nutrient pollution can also reduce visibility at outdoor recreational locations such as state and national parks and can cause damage to structures made from marble and limestone.
  • Commercial fishing and shellfish losses in the tens of millions of dollars
  • Real estate losses
    • Waterfront property values can decline due to the unpleasant sight and odor of algal blooms.


What You Can Do At Home:

  • Choose cleaning supplies that are nitrogen and phosphorus free.
  • Dispose of pet waste properly
  • Maintain septic systems
  • Use water and energy efficiently
  • Reduce driving when possible
  • Wash vehicles in proper locations (for example, at designated car washes, where the waste water is directed to the proper location)

What You Can Do In Your Yard:

  • Lawn Care:
    • Reduce or eliminate fertilizer use
    • Do not apply fertilizer close to rivers or streams
    • Do not over water lawns and gardens
    • Properly store and dispose of unused fertilizers and containers
    • Maintain yard care power equipment (lawn mowers, chain saws, etc.) to reduce nitrogen oxide emissions
  • Garden Care:
    • Plant a rain garden
    • Install a rain barrel
    • Use pervious pavers for walkways to allow water to soak into the ground rather than runoff
    • Install a green roof
    • Use yard waste in mulch and compost rather than leaving it to wash into waterways

What You Can Do In Your Community:

  • Watershed Information
  • Inform others about water quality and what they can do to help


Source: EPA – Nutrient Pollution

CLICK HERE to learn more about how HEC is pushing Governor Pence to reduce phosphorus contamination in Lake Erie.