Lake Level Update for November 2, 2021

Last week’s rains, ranging from 4-7 inches across the watershed, brought the lake level up by 1.8 feet. In recent days, the lake level reached a high of 689.84 (feet above sea level) and as of today (11/2) it is 689.74. It looks like the lake elevation has peaked at this point. If we don’t get any additional rain, the lake level will slowly begin to drop over the next several days. 

On October 26 (Tuesday of last week) the City of Canandaigua fully opened all three outlet gates (the feeder canal gate and the two main outlet gates behind Wegmans). Those gates have remained open and will continue to stay open until the lake comes down by at least 2 feet. This will likely take a few weeks.

Lake/Watershed Facts to remember:

  • The outlet gates can release the equivalent of 1.0-1.5 inches of lake level each day, depending on the lake level (the higher the lake the more water can be released).
  • You may be asking – why would the lake level still go up if we can release that amount each day? We have to remember that the drainage area is about 10 times larger than the lake surface (the lake surface area is about 10,500 acres whereas the watershed/drainage area is about 109,000 acres). With 4-7 inches of rain across the watershed in less than a week, that generates a substantial amount of runoff making its way from the surrounding land area and into the lake.
  • Last week’s storms caused the inflows to the lake to greatly exceed the ability to release water from the lake. 
  • Some historical perspective on our lake levels – in 2011 and 2014 we had lake levels reach approximately 690.25. In 1972, the remnants of Hurricane Agnes caused the lake to reach an elevation of 692.1!

We hope our watershed neighbors have remained safe and have not experienced too much damage during these recent storm events. We may continue to see floating debris in the lake and along shorelines in the coming days. Although there are no official navigation warnings from the Sheriff’s Office, it is strongly suggested that you use caution if you are boating on the lake. Please drive slowly so as to not create unnecessary wake that may further erode shoreline areas. 

The lake level on Canandaigua Lake is measured by NOAA. A link to the data can be found here or see the graph below.