Acid deposition includes acidic rain and snow as well as dry deposition, (dust and particle material) When sulfur dioxides, nitrogen oxides, or ammonia contact water; nitric acid and sulfuric acid can form. Colorado mountain streams and lakes are poorly buffered and highly vulnerable. (Buffering refers to the ability to neutralize acid. Alka Seltzer is a buffer that neutralizes excess acid in the stomach) Twenty years ago EPA identified Rocky Mountain National Park, and 8 Colorado National Forests as particularly sensitive to aquatic damage from acid deposition. Unfortunately, it is still true.

When streams or lakes become more acidic (lower pH Below 7 is acidic) fish health becomes a critical issue. In more acidic waters, fish reproductive cycles are impacted and fish populations decline. At a pH of 4-4.5 all fish die.