Monday June 16, 2025 Honeoye Lake Water Quality

Terry Gronwall
6 hours ago
3 min read

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Surface Water Temperature: ~68.2 F

Water Clarity: ~10.2 Feet

Lake Level: 803.3 Feet above sea level

Lake level at normal level

Observations: Monday (6/16/25), Water clarity was ~10.2 feet a decrease of 0.7 feet over the last week. The surface water temperature was ~68.2 F the same as last week. It was an overcast moderately windy day today which probably reduced our water clarity reading a little.

We found Gloeotrichia (lots of small spikes) of varying intensities today in the water column. We also found sparce amounts of Anabaena (Dolchospermum) (looks like a spring or chain of beans) too. Anabaena usually shows up in mid-July. So, it is about a month early. You should be watchful for Gloeotrichia and Anabaena blooms lake wide. These are both blue-green algae species. Expect to see Gloeotrichia and Anabaena blooms over the next few weeks particularly when we have 80-90 F days with calm winds. See Gloeotrichia picture on left and Anabaena picture below: We also found Ceratium, copepods, and diatoms which are not blue-green algae species today. More information on Gloeotrichia and Anabaena can be found at: https://www.honeoyelakewatershed.org/habs

Several research studies have found that most of the phosphorus that fuels Honeoye Lake’s blue-green algae blooms is released from the lake bottom sediments when the lake’s dissolved oxygen level goes below 0.5 mg/L in the deeper parts of the lake breaking the phosphors/iron bond in the bottom sediments releasing phosphorus into the water column. The dissolved oxygen (DO) level near the lake bottom at ~9 m (~30 feet) was 2.34 mg/L today. This means that phosphorus should not be released from the bottom sediments into the deepest part of the lake water at this time. Lake was stratified (i.e. had a thermocline) at ~6 m (~19.8 feet) deep. If we do not have a lake mixing event soon, we expect that the dissolved oxygen near the bottom will go anoxic (DO = <0.5 mg/L) later in June releasing phosphorus from the bottom sediments potentially fueling a blue-green algae bloom. Today's temperature and DO graphs will be added to this post in a few days.

The Curly Leaf Pond Weed is growing to the water’s surface in many areas of the lake now. Curly Leaf Pond Weed is an invasive macrophyte (Aquatic Vegetation) that grows to the water’s surface starting in late May and dies off naturally by late June or early July. Its leaves look like Lasagna.

We received a report of a panfish die off on June 8th along the SE shore of Honeoye Lake. We have reported the panfish die off to NYS DEC Region 8 Fisheries Department to investigate. If you see a panfish die off, please report it to the NYS DEC Region 8 Fisheries Department in Avon by calling 585-226-5343.

We will not start making our blue-green algae surveillance runs until early July.

As of today, there has not been any public Honeoye Lake HAB reports submitted to the DEC HABs alert map (NYHABS) yet this year.

Always use your own visual assessment before making contact with the lake water at this time of year as the blue-green algae situation can change daily if not hourly. Please regularly check the DEC HABs alert map for more detailed updates on Honeoye Lake HABs alerts:

https://experience.arcgis.com/experience/e5dec19912454731a308bbb7af605fb3/

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