Here Are The Most Polluted Lakes In Colorado
If you are the type of person who enjoys relaxing by the lake, Colorado is a state that does not disappoint. From blue lakes at over 10,000 feet to reservoirs just outside of Denver, you are never far away from a fun day near the water.
Not every lake in Colorado is 100% safe for both fishing and fun on the water. Some are polluted—not by factories, but by microcystin (toxic algae), iron, selenium, and arsenic. These elements come from a mix of natural geology and human activity. The lakes below rank among the most affected in our state.
Read More: LOOK: Colorado's Lakes Begin To Open For Boating Season
DeWeese Reservoir (Southeastern Colorado)
Colorado's Most Polluted Lakes
- DeWeese Reservoir
- Location: Custer County (near Westcliffe)
- Size: Approximately 300 acres
- Pollutant: Toxic blue-green algae (cyanobacteria)
- Safety: Swimming and other water-contact activities are prohibited during blooms; fishing is allowed with caution and should be done without water contact.
- Directions: Find DeWeese Reservoir
Cherry Creek Reservoir
Colorado's Most Polluted Lakes
- Cherry Creek Reservoir
- Location: Arapahoe County (near Denver)
- Size: Almost 880 acres
- Pollutant: Toxic algae (microcystin)
- Safety: Swimming and wading are restricted in affected areas during blooms; use caution when boating and fishing.
- Directions: Find Cherry Creek Reservoir
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North Sterling Reservoir
Colorado's Most Polluted Lakes
- North Sterling Reservoir
- Location: Logan County (near Sterling)
- Size: Nearly 3,000 acres
- Pollutant: Toxic algae (microcystin)
- Safety: Swimming and wading are prohibited in certain areas during blooms; use caution when boating and fishing.
- Directions: Find North Sterling Reservoir
Barr Lake (Near Brighton)
Colorado's Most Polluted Lakes
- Barr Lake (near Brighton)
- Location: Adams County (Lochbuie)
- Size: Approximately 1,900 acres
- Pollutant: Toxic algae (microcystin)
- Safety: Recreational activities may be restricted during blooms; always check current advisories.
- Directions: Find Barr Lake
John Martin Reservoir
Colorado's Most Polluted Lakes
- John Martin Reservoir
- Location: Bent County (southeastern Colorado)
- Size: Approximately 11,600 acres
- Pollutants: High amounts of selenium and arsenic
- Safety: If you fish John Martin Reservoir, check local advisories before consuming anything you catch. Water contact advisories may also be in place.
- Directions: Find John Martin Reservoir
Danau Meredith Reservoir
Colorado's Most Polluted Lakes
- Danau Meredith Reservoir
- Location: Crowley County (near Ordway)
- Size: About 4,000 acres
- Pollutant: Elevated levels of selenium
- Safety: Consult any local advisories at Lake Meredith before water contact and fishing.
- Directions: Danau Meredith Reservoir
Lake Henry
Colorado's Most Polluted Lakes
- Lake Henry
- Location: Crowley County (near Ordway)
- Size: Approximately 1,100 acres
- Pollutant: Elevated levels of iron
- Safety: Water-contact activities should be approached with caution; consult local advisories.
- Directions: Find Lake Henry
Read More: Colorado is Home to Some of America’s Best Summertime Lakes
Adobe Creek Reservoir (Blue Lake)
Colorado's Most Polluted Lakes
- Adobe Creek Reservoir (Blue Lake)
- Location: Bent County (southeastern Colorado)
- Size: Approximately 5,000 acres
- Pollutants: High amounts of selenium and arsenic
- Safety: Check for local advisories before fishing and water contact.
- Directions: Find Adobe Creek Reservoir
LOOK: See the Top 10 Most Polluted Zip Codes in Colorado
Industry, traffic, and even wildfires all contribute to the overall pollution found in the state of Colorado. Have you ever wondered which locations in Colorado have to deal with the highest amount of pollution? Take a look at the ten worst zip codes for pollution in Colorado by scrolling through the photos below.
Gallery Credit: Wesley Adams
LOOK: Colorado Cities Ranked 'Dirtiest In America'
Lawnstarter's list of the 300 'Dirtiest Cities in America' ranks locations across the country based on factors like infrastructure, resident satisfaction, living conditions, and pollution. Scroll through the ten Colorado cities that made this year's dirty list in the gallery below.
Gallery Credit: Wesley Adams
UP NEXT: Which One of Colorado's Major Rivers Is the Most Polluted?
Just how healthy are Colorado's major rivers? Which Colorado River is the most polluted? We're looking at Colorado's eight major river basins to find out which ones are in good shape and which rivers need some TLC.
Gallery Credit: Wesley Adams