Dissolved oxygen levels are a critical indicator of water quality.
Oxygen dissolved in water sustains life in aquatic communities. When oxygen levels are too low, many species can’t survive. Several factors affect dissolved oxygen levels, including flow, temperature, and the amount of organic material in lakes or rivers. For example, cold, moving water tends to contain more dissolved oxygen; warm, stagnant water contains less. Because bacteria consume oxygen from decaying organic matter, like leaves, excess organic material can lead to oxygen deficiency and create “dead zones” in lakes.
On Snapshot Water Monitoring Day, volunteers measure dissolved oxygen levels at sites throughout the watershed. Each year, we’ve found areas of moderate to critical oxygen depletion, some years more than others. Generally, this can be attributed to low water levels and too much decaying organic matter.
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