Seneca Lake was carved out of bedrock over 10,000 years ago by glaciers, it is the deepest freshwater lake east of the Mississippi River outside of the Great Lakes. The lake’s shoreline is found within Seneca, Ontario, Yates and Schuyler Counties.




Interesting Facts

38 miles long

3.2 miles at greatest width

1.9 miles wide on average

633 feet deep, at maximum

66.3 square miles or about 42,400 acres

4.2 Trillion gallons of water

75 miles of shoreline

11 municipalities rely on the lake for public water systems

100,000 people rely on Seneca Lake as their primary water source


What Science Tells Us About Seneca Lake 

John Halfman, Ph.D., teaches in the Department of Geoscience and Environmental Studies Program at Hobart and William Smith Colleges in Geneva, NY.