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Nutrient Pollution
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Photos of Lakes Before and After Algal Blooms

Nutrient pollution from a variety of sources can turn waters green with algae. Algal blooms hurt wildlife, spoil recreation, and can be toxic to people and animals. The photos show lakes and ponds around the country that have been affected by algal blooms.

On this page:
  • Harlem Meer, New York
  • Lake Hodges, California
  • Lake Erie, Ohio
  • Shelburne Pond, Vermont
  • Cushwa Basin, Maryland
  • Oneida Lake, New York

*All photos used with permission from the photographer or through a Creative Commons license.


Harlem Meer, New York

Harlem Meer

Photo: Bill Benish, Flickr (refer to original).

Harlem Meer during an algae bloom

Photo: Brad W. (refer to original).

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Clean waterGreen water

New Yorkers and tourists love Harlem Meer for catch-and-release fishing and waterside strolling, but summertime algal blooms can kill off the fish and cause a stink that drives people away. Wildlife like herons and turtles are also harmed by these blooms.

Lake Hodges, California

Lake Hodges

Photo: Flickr user.

Lake Hodges during an algae bloom

Photo: Carey N. (refer to original).

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Clean waterGreen water

Lake Hodges is a reservoir in southern California used for drinking water and irrigation as well as recreation like fishing, boating and hiking. Algal blooms here have not only spoiled outdoor activities but at times have caused local utilities to stop drawing water until the algae clears.

Lake Erie, Ohio

Lake Erie

Photo: U.S. EPA

Lake Erie during an algae bloom

Photo: U.S. EPA

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Clean waterGreen water

Lake Erie is the warmest and shallowest of the Great Lakes, which makes it susceptible to algal blooms. It is also a source of tap water to the region. In 2014, a toxic algal bloom in the lake's western basin forced Toledo, Ohio, to issue an advisory to over half a million people, telling them to avoid all contact with their tap water.

Shelburne Pond, Vermont

Shelburne Pond

Photo: Bob Von Bruns, Flickr (refer to original).

Shelburne Pond during an algae bloom

Photo: Lisa B. (refer to original).

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Clean waterGreen water

Shelburne Pond is just 10 miles from Burlington, Vermont, and is used for fishing, boating and hiking. Excess nutrients in the pond cause algal blooms that deter people from enjoying this scenic waterbody.

Cushwa Basin, Maryland

Cushwa Basin

Photo: Doug Kerr, CC BY-SA 2.0, Flickr (refer to original).

Cushwa Basin during an algae bloom

Photo: Eva M. (refer to original).

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Clean waterGreen water

Cushwa Basin, in Williamsport, Maryland, greets hikers, joggers and cyclists along the C & O Canal Towpath. Bad odors produced by algal blooms drive people away and keep them from enjoying views of the historic barn and other nearby landmarks.

Oneida Lake, New York

Oneida Lake

Photo: Carol Bednar, Flickr (refer to original).

Oneida Lake during an algae bloom

Photo: Amy H. (refer to original).

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Clean waterGreen water

Oneida Lake is a popular vacation spot in New York. Toxic algal blooms, which can cause skin and eye irritation to people and kill dogs, have closed beaches here to swimmers and boaters, disrupting tourism and hurting local businesses. Some years, beaches on Oneida Lake have been closed for all but just a handful of days due to algal blooms.

  • Nutrient Pollution
  • The Problem
  • Sources and Solutions
  • The Effects
  • Where This Occurs
  • What You Can Do
  • Policy and Data
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Last updated on August 8, 2022
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