News, Events, and Culture for

SOUTHERN FINGER LAKES

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Sunrise: 5:49 am
Sunset: 8:43 pm

News, Politics, and Culture for

SOUTHERN FINGER LAKES

Why has Cayuga Lake been so colorful?

This Sentinel-2 satellite image from July 11 shows a suspected whiting event

From the Cayuga Lake Watershed Network

If you’ve been on or near Cayuga Lake over the last week or so, you may have noticed an almost Caribbean-blue color (especially on sunny days that were not affected by wildfire smoke). Observations from around the lake suggest much of what we’re seeing is actually consistent with a natural phenomenon called a whiting event, in addition to harmful algal blooms (HABs), which have been reported along the shorelines.

A whiting event occurs when tiny crystals of calcium carbonate (the same mineral found in limestone) form and become suspended in the water, scattering sunlight and creating a brilliant turquoise or milky blue appearance. The Finger Lakes are naturally rich in dissolved calcium because of the region’s limestone geology, making these events possible under the right conditions. Unlike HABs, Whiting events aren’t toxic.

Check out this week’s HABs newsletter to learn more!

https://mailchi.mp/cayugalake/2026_habs_4

Have you seen the lake’s unusual color this week? Share your photos in the comments!