Ammonia Fact Sheet

Ammonia is a colorless, pungent gaseous compound of hydrogen and nitrogen that is highly soluble in water. It is a biologically active compound found in most waters as a normal biological degradation product of nitrogenous organic matter (protein). It also may find its way to ground and surface waters through discharge of industrial process wastes containing ammonia and fertilizers. Ammonia has been used in municipal treatment systems for over 70 years to prolong the effectiveness of disinfection chlorine added to drinking water. The addition of ammonia enhances the formation of chloramines (which may create objectionable tastes), and it reduces the formation of chlorination by-products which may be carcinogenic. Partial adsorption of chloramines (from city supplied water) by GAC may liberate ammonia. When dissolved in water, ammonia (NH3) reacts to form ammonium (NH4+) and hydroxyl (OH-) ions.