The Water Cycle

1. Water is evaporated from bodies of water. Some water is from the transpiration of trees.
2. Evaporated water condense into clouds, which float in the sky until they are heavy enough to turn into rain.
3. The clouds precipitate, sending water back down to the surface.
4. Some water infiltrate into the ground, going into underground rivers/lakes called aquifers.
   Other water land in bodies of water.
   Water on higher surfaces can also run down along the surface without going into the ground or rivers (surface runoff)
5. The cycle repeats. Infinitely.

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However, there are certain problems with the sustainability of the cycle, due to human interferences.

The amount of drinkable freshwater is decreasing, due to high amounts of chemicals/waste being dumped into the water. The waste in the water makes it too expensive/difficult to treat.

This lack of drinkable freshwater leads to humans taking more water from aquifers, faster than they can replenish.

Sometimes, even the aquifers have traces of chemicals in them because the water cannot be filtered completely with only natural filtration anymore :C

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Impacts of Surface Runoff

Algae Blooms

• caused by excessive fertilizer/pesticides in water
• takes out the nutrients and oxygen in water
  • kills aquatic life
    • chances of becoming a dead zone
  • lowers the oxygen levels

Turbidity

• too much debris/dirt that makes the water unclear
• very bad for lakes/rivers because it blocks sunlight
• trees help prevent turbidity, but deforestation ruining that

Levees and Dikes

• sandbags walls, concrete walls, etc.
• prevents mudslides, flooding, and the like
• prevents surface runoff