Pollutants & Sources

Phosphorus Ammonia & Nitrite Combined Sewer Overflows Mercury & Other Industrial Wastes Sediment Loading: Tully Valley Mudboils Salinity Nonpoint Source Pollution

Ammonia and nitrite are nitrogen compounds that are discharged into Onondaga Lake in amounts that can be harmful to fish and other aquatic life.

What are Ammonia and Nitrite?

Ammonia and nitrite are forms of nitrogen which in high concentrations can be toxic to fish and other aquatic life. The concentrations of ammonia and nitrite that prevail in Onondaga Lake exceed environmental standards established to protect fish and other aquatic life from their toxic effects. These standards were developed to prevent fishkills and to protect fish spawning and free migration. Toxic concentrations of ammonia depend on a complex relationship between the amount of ammonia, pH and the temperature of the water.

Effects of Chronic Ammonia Exposure

Although ammonia levels may not be toxic enough to cause a fishkill in Onondaga Lake, chronic exposure to elevated ammonia levels can reduce natural fish spawning and restrict migration patterns. Ammonia concentrations also exceed New York State toxicity standards in both Onondaga Lake's outlet and the Seneca River. This is caused in part by the outflow of ammonia-rich lake water to the river.

Ammonia Sources

Ammonia is supplied to the lake from both point and non point sources. However, Metro is the dominant source of ammonia to the upper waters on Onondaga Lake. More than 90% of the lake's ammonia input comes from Metro. This is because the existing facility was never intended to remove significant quantities of ammonia from sewage. The second largest source of ammonia to the lake comes from the most recently active Allied-Signal waste beds located on Nine Mile Creek. Their input represents about 4% of the total ammonia load to Onondaga Lake.