Emerald Pool is a small, shallow lake, with an area of less than one acre. It is located about 80 meters above Vernal Fall in Yosemite National Park. It is named for its deep green color, which is caused by algae living on the rocks at the bottom of the pool. In the summertime during diminished water flow, the Silver Apron (a smooth granite slope over which the Merced River flows into the Emerald Pool) is frequently (albeit illegally) used by hikers as a water slide. Swimming or wading in the Emerald Pool or entering the Silver Apron is prohibited by the National Park Service since waders or swimmers have been swept over Vernal Fall and killed, and people sliding down Silver Apron risk collision with hidden rocks at its lower end. [1] [2] This prohibition is clearly marked with signs.
