Onondaga Lake is northwest of the city of Syracuse, New York and south of Lake Ontario. Water outflows from the lake to Lake Ontario through the Oswego River. The lake is five miles (8 kilometers) long and a mile (1.5 kilometers) wide. It has an area of 4.6 square miles (11.9 square kilometers) and has a maximum depth of 73 feet (22 meters). Although it is near the Finger Lakes region, it is not traditionally counted as one of the Finger Lakes.
Around 1450 or possibly earlier, Onondaga Lake was the site of the founding of the Haudenosaunee (Iroquois) Confederacy. According to legend, at this spot the warlike Onondaga chief Tadodaho was persuaded by Hiawatha and Deganawidah (the Peacemaker) to accept the Great Law of Peace. Historically, the lake and the surrounding area was a site of salt springs and later salt mining. The salt was distributed throughout the north-east via the Erie Canal; Irish immigrants working in this industry created the local dish of salt potatoes.
Today, Onondaga Lake is a severely polluted lake. Onondaga Lake has been described as one of the most polluted lakes in the United States,primarily due to industrial dumping. It is advised not to fish or swim in the lake. The lake has high levels of mercury, salt, phosphorus, and ammonia. The EPA has declared it a hazardous waste site. Recently, an effort has been made to clean up the water in the lake. The lake is also the subject of a land rights action filed in 2005 by the Onondaga Nation.
The lake is surrounded by the city of Syracuse and the suburban area of Solvay, a center of industry in the Syracuse area. Many of the companies in the areas of Solvay and Syracuse are held to blame for the lake's high concentrations of hazardous chemicals. Honeywell International (formerly AlliedSignal, which acquired Honeywell and took its name) is being held responsible for the clean up of the lake for their mass depositing of mercury and salt over the years. From a large municipal discharge the lake in the summer is generally covered in many areas with algae that creates a vile odor that can be smelled for miles. Onondaga County is spending $500 million on a 15-year project to stop polluting the lake with sewage by 2012. The county is under a federal court order to make the lake safe for swimming and fishing and comply with the federal Clean Water Act.