Below are the weekly lake reports provided by Terry Gronwall

A general statement about the lake is :

  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.  The DEC will report on their assessment of our
blue-green algae bloom situation for this week late Friday afternoon on
their BGA alert web page.

The weekly water quality data for 2017 can be found in the following file: 2017 Water Quality Data Deep 9 meter.pdf

The Gronwall's visual BGA Update for 

    Monday morning (10/23) 

There was only very light to light algae visible
in the surface water at all of our monitoring sites.  We observed no surface
algae scum at any of our monitoring sites.  However, as recently as last
Saturday afternoon a suspicious algae bloom was reported along the North and
Northeast shore.

  This will be our last blue-green algae and water quality report of the
2017 season.  Time to put our boat in winter storage and take our docks and
hoists out for the winter.

	Mon. 10/16	Mon. 10/23	Weekly Change
Surface Water Temperature (F):	63.7	61.34	-2.36
Water Clarity (Ft):	6.89	7.22	0.33
Lake Level (Ft):	803.17	803.18	0.01
Lake Level Relative to Weir (Ft):	-0.33	-0.32	0.01

    Monday morning (10/16)

There was only a very light trace of algae
visible in the surface water at all of our monitoring sites.  We observed no
surface algae scum at any of our monitoring sites.  An amazing change from
last Tuesday due to the cold, rainy, windy weather we had over the last
week....

	Tue. 10/10	Mon. 10/16	Weekly Change
Surface Water Temperature (F):	66.7	63.7	-3
Water Clarity (Ft):	5.91	6.89	0.98
Lake Level (Ft):	803.14	803.17	0.03
Lake Level Relative to Weir (Ft):	-0.36	-0.33	0.03

 

Tuesday morning (10/10)

There was very light to light algae visible in
the surface water at all of our monitoring sites including our open water
site.  We observed a very light surface algae scum at several of our
monitoring sites.  However, in crossing open water to go from one near shore
monitoring site to the next we would occasionally come across patches
(200-300' wide and 300-500' long) of dense BGA with surface scum.  Then the
open water would only have very light BGA visible again.

    Wednesday morning (10/11), we were out on the lake again for 2 hours.
With a light rain and ~8 MPH NE wind we found no open water patches of BGA.
Near shore areas were relative clear except for the extreme south end of the
lake where the wind was blowing the algae.  The algae conditions are highly
variable due to the weather at this time.

 

	Mon. 10/2	Tue. 10/10	Weekly Change
Surface Water Temperature (F):	67.1	66.7	-0.4
Water Clarity (Ft):	5.25	5.91	0.66
Lake Level (Ft):	803.05	803.14	0.09
Lake Level Relative to Weir (Ft):	-0.45	-0.36	0.09

   Monday Morning (10/2)

There was very light to medium algae visible in
the surface water at all of our monitoring sites including open water.  We
observed a very light surface algae scum at several of our monitoring sites.


    Honeoye Lake experienced a mixing event sometime over the last few days
due to the cold weather and wind.  Surface water temperature was 67.1 F
today a decrease of 9.2 F from Monday (9/25/17).  Since the lake had
re-stratified in mid-September, it is our expectation that this weather
generated mixing event brought nutrients from the water near the bottom of
the lake and mixed them in the water column providing the fuel for a mild
resurgence of a blue-green algae bloom this week.

	Mon. 9/25	Mon. 10/2	Weekly Change
Surface Water Temperature (F):	76.3	67.1	-9.2
Water Clarity (Ft):	3.9	5.25	1.35
Lake Level (Ft):	803.12	803.05	-0.07
Lake Level Relative to Weir (Ft):	-0.38	-0.45	-0.07

 

  Monday Morning (9/25)

We found light to medium algae visible in the
surface water at all of our monitoring sites including open water.  We
observed surface algae scum at many of our monitoring sites. 

    The weather has been ideal for blue-green algae blooms.  Temperatures in
the mid-80's F, calm wind, and sunny skies.  Most lakes including Honeoye
Lake in our region have been confirmed with blue-green algae blooms
recently.  Therefore, it is very important to review the advice on the DEC
and DOH web sites about how to identify a blue-green algae bloom and avoid
contact if you see a suspicious bloom.

	Mon. 9/18	Mon. 9/25	Weekly Change
Surface Water Temperature (F):	73.9	76.3	2.4
Water Clarity (Ft):	4.3	3.9	-0.4
Lake Level (Ft):	803.16	803.12	-0.04
Lake Level Relative to Weir (Ft):	-0.34	-0.38	-0.04

    Monday Morning (9/18)

We found light to heavy algae visible in the
surface water at all of our monitoring sites.  We observed surface algae
scum at many of our monitoring sites.  The surface scum was less dense than
late last week. 

    We experienced a thermocline disturbance in mid-August and a complete
water column mixing event around August 28th.  Surface water temperature was
73.9 F on (9/18/17) an increase of 7.0 F from Monday (9/11/17).  These
events are the most likely cause of the BGA bloom we have been experiencing
recently.

    Total phosphorus (TP) before these water column mixing events was ~25
ug/l and after ~60 ug/l.  The EPA criteria to be on their impaired water
body list is TP >20 ug/l.  Therefore, it is obvious that our TP level was
not extraordinarily high until after our August water column mixing events.

	Mon. 9/11	Mon. 9/18	Weekly Change
Surface Water Temperature (F):	66.9	73.9	7
Water Clarity (Ft):	4.3	4.6	0.3
Lake Level (Ft):	803.16	803.16	0
Lake Level Relative to Weir (Ft):	-0.34	-0.34	0

   Monday Morning (9/11)

We found light to heavy algae visible in the
surface water at all of our monitoring sites.  We observed light brown algae
surface scum at many of our monitoring sites.  Some sites with surface scum
had an odor of dying blue-green algae.    

  Surface water temperature dropped another 2.2 F over the last week.  69.1
F on 9/4 and 66.9 F on 9/11.

 

	Mon. 9/4	Mon. 9/11	Weekly Change
Surface Water Temperature (F):	69.1	66.9	-2.2
Water Clarity (Ft):	3	4.3	1.3
Lake Level (Ft):	803.09	803.16	0.07
Lake Level Relative to Weir (Ft):	-0.41	-0.34	0.07

 

  Monday Morning (9/4)

We found very light to heavy algae visible in the
surface water at all of our monitoring sites.  Heavier algae concentrations
in the southern part of the lake.  We did not observe any algae surface
scum.  Visually there looked like less blue-green algae than a week ago.
However, we did receive one lake resident report of suspicious algae surface
scum in a near shore stagnant water area after we completed our morning
blue-green algae monitoring run.  We plan to check this area tomorrow.

  The lake has been very well mixed temperature and dissolved oxygen wise
for over a week.  The surface water temperature has dropped 3.6 F over the
last week.  The lake is behaving like fall has arrived....

	Mon. 8/28	Mon. 9/4	Weekly Change
Surface Water Temperature (F):	72.7	69.1	-3.6
Water Clarity (Ft):	3.3	3	-0.3
Lake Level (Ft):	803.14	803.09	-0.05
Lake Level Relative to Weir (Ft):	-0.36	-0.41	-0.05

 

Monday Morning (8/28)

 We found very light to medium algae visible in
the surface water at all of our monitoring sites.  Very light algae surface
scum observed at a few of our monitoring sites.    Surface water temperature
was 72.7 F on Monday (8/28/17) a decrease 2.9 F from Monday (8/21/17). 

  We got ~1.5" of rain last Tuesday afternoon/evening which caused a mixing
event to occur.  We feel that this was the trigger event for our increase in
our BGA bloom starting last Thursday.  

  

	Mon. 8/21	Mon. 8/28	Weekly Change
Surface Water Temperature (F):	75.6	72.7	-2.9
Water Clarity (Ft):	4.3	3.3	-1
Lake Level (Ft):	803.12	803.14	0.02
Lake Level Relative to Weir (Ft):	-0.38	-0.36	0.02

  Monday Morning (8/21)

 we found only very light to light algae visible
in the surface water at all of our monitoring sites.  No algae surface scum
observed at any of our monitoring sites.  There was a significant
improvement from late last week.

  Surface water temperature was 75.6 F on Monday (8/21/17) an increase 2.6 F
from Monday (8/14/17). 

  The last week has been very dynamic for the lake.  Early last week there
was only very light blue-green algae visible.  Then we had a sharp rain
storm Tuesday (8/15) late afternoon.  Wednesday (8/16) we detected that the
storm caused a thermocline disturbance.  This may have caused legacy
nutrients from the bottom sediments to be transported to the surface water.
This probably fueled the isolated blue-green algae blooms that were visible
the later part of last week.  This event seems to have run its course based
on the light amount of visible blue-green algae observed this morning
(8/21).

	Mon. 8/14	Mon. 8/21	Weekly Change
Surface Water Temperature (F):	73	75.6	2.6
Water Clarity (Ft):	5.9	4.3	-1.6
Lake Level (Ft):	803.11	803.12	0.01
Lake Level Relative to Weir (Ft):	-0.39	-0.38	0.01

 

  Tuesday Morning (8/15)

We found only very light algae visible in the
surface water at all of our monitoring sites.  No algae surface scum
observed at any of our monitoring sites.  Our gleotrichia bloom appears to
have ended.

  Surface water temperature was 73.0 F on Monday (8/14/17) a decrease of 1.5
F from Monday (8/7/17).  The surface water temperature was ~79 F on August
2nd.  We have had a 6 F surface water temperature decrease in the last 2
weeks.  This large a surface water temperature decrease is very unusual in
August.

	Mon. 8/7	Mon. 8/14	Weekly Change
Surface Water Temperature (F):	74.5	73	-1.5
Water Clarity (Ft):	5.9	5.9	0
Lake Level (Ft):	803.17	803.11	-0.06
Lake Level Relative to Weir (Ft):	-0.33	-0.39	-0.06

Monday August 7th:

    Monday Morning (8/7), we found very light to light algae visible in the
surface water at most of our monitoring sites.  Only our North Shore site
had green looking surface water.  This was probably caused by Monday's South
wind.  We did not see any blue-green algae surface scum at any of our
monitoring sites.  The gleotrichia bloom appeared to be subsiding. 

  Surface water temperature was 74.5 F a decrease of 2.0 F from Monday
(7/31/17).  This is a very large decrease in water temperature over a one
week time period.  Water clarity increased by 2.3 feet to 5.9 feet.

	Mon. 7/31	Mon. 8/7	Weekly Change
Surface Water Temperature (F):	76.5	74.5	-2
Water Clarity (Ft):	3.6	5.9	2.3
Lake Level (Ft):	803.25	803.17	-0.08
Lake Level Relative to Weir (Ft):	-0.25	-0.33	-0.08

Monday, July 31, 2017

  

  Monday Morning (7/31), with calm winds, we found blue-green algae with
surface scum in several isolated near shore areas.  Particularly near shore
areas that are protected from the wind with dense aquatic vegetation.  This
means that the blue-green algae gets trapped in these areas.   Water clarity
increased about one (1) foot over the last week as the effects of last
Sunday's rain storm abate.

	Mon. 7/24	Mon. 7/31	Weekly Change
Surface Water Temperature (F):	77.9	76.5	-1.4
Water Clarity (Ft):	3.6	4.6	1
Lake Level (Ft):	803.52	803.25	-0.269
Lake Level Relative to Weir (Ft):	0.02	-0.25	-0.269

  

  Monday Morning (7/24)

With calm winds, we found blue-green algae in
several isolated near shore areas, particularly along the north shore, and
in open water.  The lake was very turbid due to our Sunday afternoon rain
storm.  This caused a decrease in water clarity of about 4.5 feet.  

	Mon. 7/17	Mon. 7/24	Weekly Change
Surface Water Temperature (F):	77.7	77.9	0.2
Water Clarity (Ft):	8.1	3.6	-4.5
Lake Level (Ft):	803.37	803.52	0.149
Lake Level Relative to Weir (Ft):	-0.13	0.02	0.149

Monday July 17th:

With calm winds, we found blue-green algae in
several isolated near shore areas and few places on open water.  The surface
water temperature was 77.7 F.  This was an increase of 2.9 F from Monday
July 10th.  This is a very large temperature increase for a one week time
period.  The lake's water level is close to normal.

Honeoye Lake Data
	Mon. 7/10	Mon. 7/17	Weekly Change
Surface Water Temperature (F):	74.8	77.7	2.9
Water Clarity (Ft):	8.2	8.1	-0.1
Lake Level (Ft):	803.17	803.37	0.2
Lake Level Relative to Weir (Ft):	-0.33	-0.13	0.2