Lake Level Information

Cayuga Lake Water Levels

Lake level extremes, either high or low, can affect shoreline habitats adversely, cause shoreline property damage, and interfere with recreational uses of the Lake. Information is provided here to help shoreline owners and recreationists know current and projected lake levels. 

Cayuga Lake water levels are managed by a dam at Mud Lock at the north end of the Lake. The lake level varies seasonally about 4.4 feet from spring’s high to winter’s low based on long-term averages. However, unusual weather conditions within the region can and do cause levels to exceed these levels, on both the high and low ends. This has been the case with extreme weather events in recent years.

Ability to manage Cayuga Lake is difficult in part because it is dependent on the level of the Seneca River, into which Cayuga Lake drains. In summer the river is typically 9 feet lower than the Lake and regulation of the Lake level can be achieved. But, severe weather in either the summer or winter can have the River level near flood conditions and lowering Cayuga Lake would create damaging flood conditions for the River homes, limiting the Lake water release. Release of water from Seneca Lake is managed by the Gravity Renewables, owner of hydropower plants in Seneca Falls and Waterloo. They watch Seneca Lake levels and make more of less electric power as levels change.The interaction of these levels can be monitored on the Lake Level Chart linked below. 

Current and Projected Lake Level

The New York State Canal Corporation, which operates the dam at Mud Lock, provides this chart of current and projected lake levels that is updated at least weekly. The Canal Corporation is responsible for maintaining water levels of the canal system within the Oswego River Basin for navigational purposes.

The United States Geological Survey maintains a lake level gauge on Cayuga Inlet at Ithaca and provides this chart of current lake levels. Scroll down on the page to see the chart. 

Important Note: One must be careful in comparing the measures of Cayuga Lake level at the USGS gauge at the Ithaca Inlet and at the Mud Lock gauge at the north end because they do not use the same datum.

  • The USGS datum is NGVD 1929 (an older topographic map benchmark)
  • The Mud Lock datum is BCD (a “local” upstate NY datum, 1910 Barge Canal).

According to the National Weather Service, Advanced Hydrologic Prediction Service website for Cayuga Lake at, there is about a 1.3 ft difference between the two datum, that is NGVD29 + 1.3′ = BCD. This NWS website, cited on the CLWN website, also provides a continually updated observation of the lake level at Mud Lock.


Flood Outlook

The National Weather Service, Advanced Hydrologic Prediction Service provides this chart of current lake level and current flood outlook

Low lake level at Myers Point on Cayuga Lake during winter