Degrading Water Quality

There are many ways that climate change can impact water quality. Often the effects occur at the source of drinking water, namely in rivers, lakes, and reservoirs. First, increased precipitation can increase nutrient runoff. Nutrient runoff sparks severe algal blooms in bodies of water. Algal blooms can make water supply dangerous to drink while decreasing oxygen levels and killing fish. This decreasing oxygen level primes the body of water for more algal growth, continuing in a dangerous cycle. Furthermore, low-oxygen water is more corrosive and can damage water pipes and other water infrastructure, which only decreases water supply. Similarly, nutrient and contaminant runoff from the precipitation pollutes groundwater, the largest source of drinking water. The same thing can also happen with fertilizer runoff, polluting surface water. Additionally, rising sea levels result in saltwater contaminating freshwater supplies.

All of these effects compound to contribute to the global water crisis, which affects billions of people. Water quality also is a major factor in human health, compounding climate change's effects on human health.