Category Archives: Technical Lake Stuff

May 2021 Water Level Chart Archived

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May 2021

I have archived the May 2021 Water Level Chart (at left). The dearth of precipitation which has plagued us all winter continued through the month of May. At the end of April we were 3.50 inches short of normal for the year and today, on the last day of May, having received an underwhelming 1.91 inches for the month (normal for May is 3.71 inches), we’re now worse off at 5.20 inches short of where we would be in a normal year. It would have been even worse but for the 0.93 inches of rain we received on Memorial Day, the last day of the month. The timing was lousy but the rain itself was very much needed and I’m glad we got it. It also seemed like a fitting end to a long cold weekend that had me burning wood in my stove again; I’m OK with putting on a sweater in the house but I draw the line at wearing gloves at dinner! The three day weekend also marked the start of our Courtesy Boat Inspection program and unsurprisingly, we didn’t inspect any boats entering or leaving the lake. It was not the 3 day weekend you were looking for! Continue reading

02 May 2021: Water Quality Monitoring Resumes for 2021!

46 Years of Secchi Disk Measurements

Kelsie French and I got out on the lake today to start Water Quality Monitoring for the 2021 season, a spring ritual that has been taking place on Clary Lake since 1975. All the data we collect is periodically sent to the Lake Stewards of Maine (formerly the Volunteer Lake Monitor Program) where it is checked for validity and accuracy. My father Stuart Fergusson was the first person to submit secchi disk readings for Clary Lake in 1975. David Hodsdon started accompanying him at about the same time and according to DEP’s Linda Bacon, David took over completely in 1991. For many years David worked solo until Jack Holland joined him around 2001. I got involved in 2013 and Kelsie French, our newest water quality monitor, started in 2018. After 44 years on the lake, David retired after completing the 2019 season and Jack Holland has taken a hiatus from water level monitoring. We hope he resumes sometime soon! Becoming a water quality monitor requires certification by the Lake Stewards of Maine, and periodic recertification. Continue reading

April Water Level Chart Archived

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April 2021

I have archived the April 2021 Water Level Chart (at left). The dearth of precipitation that has plagued us for much of last year and for the first three months of this year has continued into April with total monthly rainfall amounting to only 3.12 inches, a good deal of which we received on the last day of the month. This is well below the April average of 3.87 inches. Year to date we’re 3.5  inches below normal and we’re only a third of the way through the year. This does not bode well for ground water supplies this summer, even if precipitation returns to something like normal. The USDA has categorized this area of Maine as “Abnormally Dry” (see below) which is certainly an unusual condition for Springtime in the Northeast. Nationwide, drought conditions are much worse as this next graphic from the Maine Climate Office clearly shows: Continue reading

March 2021 Water Level Chart Archived

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March 2021

I have archived the March 2021 Water Level Chart (at left). Precipitation was again slow to accumulate in March and we ended the month with only 2.00 inches of rain, well below the monthly average of 3.77 inches. Despite the lack of snow pack and the lack of rain, we did succeed in filling the lake before the end of the month, and on pretty much the same date as last year. We did this by adding one or two stop logs, gradually raising the lake level (the black dashed line on the chart represents the height of stop logs in the weir). The dam’s gate was closed for the entire month and was only opened 1 foot on the 30th in anticipation of a significant rain event on expected on April 1st, no fooling! Filling the lake in the spring is made easier when there is more water to work with; we were able to do it this spring largely at the expense of meeting the minimum flow requirement. We started the month with the lake level down -1.15 feet below the HWM and ended up on March 31st with the lake at -0.20 feet below the HWM with a little water running over the dam. The ice went out on March 29th. Continue reading

February 2021 Water Level Chart Archived

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February 2021

I have archived the February 2021 Water Level Chart (at left). Precipitation was slow to accumulate this month but a rain/snow storm on the 27th finally pushed us to 2.67 inches for the month, just a hair above the February average of 2.61 inches. Year to date however we’re still the better part of an inch below normal and without any snow pack to speak of, we are looking at a drier than usual Spring. Most of Maine is not in drought this winter but there are some areas on the coast not far south from here that are considered “abnormally dry.” A lot can (and probably will) change between now and April. Continue reading

January 2021 Water Level Chart Archived

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January 2021

I have archived the January 2021 Water Level Chart (at left). The drought conditions that plagued us last year have returned early in 2021 with January’s precipitation of 2.16 inches falling considerably short of the normal monthly precipitation of 3.19 inches. February is the month with typically the lowest (2.61 inches) monthly precipitation of the year. We’re going to start February with a decent shot of snow in a couple of days. Hopefully we’ll develop a good snow pack by spring. Continue reading

Lake Stewards of Maine 2021 Winter Newsletter Is Out

Lake Stewards of Maine (formerly Maine Volunteer Water Monitoring Program) has mailed their Winter 2021 newsletter, The Water Column. Print copies are in the mail and should arrive any day. As usual, they’ve produced a great publication. I especially liked the articles on “Influences of Extreme Weather on Maine Lakes in 2020” (on page 16) and Late Season Algae “Flash Blooms” in Lakes” (on page 26), both by LSM Executive Director Scott Williams. Also, the article “Changes to Communication & Technology in
the Past Few Years and the Spurs of CoViD-19″ by Tristan Taber was quite interesting. Continue reading

December 2020 Water Level Chart Archived

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December 2020

And so we arrive at the end of another year. I have archived the December 2020 Water Level Chart (at left) and much like 2020 was a roller coaster year, December was a roller coaster month in terms of rainfall and resulting water level fluctuations! On the last day of November we received 1.75 inches of rain followed by 0.76 inches more the next day. This pushed the lake level from 0.68 feet below the HWM to 0.07 feet above the HWM almost overnight, resulting in water flowing over the top of the dam for the first time since last spring. Then on December 5th we received 2.00 inches of rain which drove the lake level even higher, to 0.18 feet above the HWM, despite our efforts to mitigate the lake level rise. From there the lake fell more or less steadily to the month low of 1.34 feet below the HWM. More rain on the 23rd and 25th of the month again pushed the lake level up to a little less than 1 foot below the HWM. It would have gone a lot higher if we hadn’t opened the gate to drain off more water in anticipation of the additional rainfall. The heavy rains, warm temperatures, and high winds on Christmas day resulted in most of the lake’s ice melting off. The lake completely froze over for the first time on December 19th. At the time of this writing, most of the lake remains ice free. Continue reading

19 December 2020: Clary Lake Frozen Over

Clary is fully iced over as of December 19th.

After consulting with the two Davids (David Hodsdon and David Knight) we’ve concluded that Clary has finally iced over but it will likely at least partially melt off again on Christmas day as we’re expecting a storm bringing an inch or more of rain with temps in the 50’s. Time will tell! As cold as it’s been this month, I expected the lake to freeze before this but heavy rains at the end of November and beginning of December have resulted in a lot of water moving through the lake and as you know, moving water resists freezing. Also, the addition of lots of rain to the lake raises the temperature if only slightly, and this slows down freezing as well. Continue reading

November 2020 Water Level Chart Archived

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November 2020

I have archived the November 2020 Water Level Chart (at left). We were a little worried that the fall drought conditions were going to continue into November so we’ve been operating the dam so as to maintain a decent store of water going into Winter, releasing only the required minimum flows. For the first 3 weeks the dearth of rain did continue and the lake level had fallen to 1 foot below the HWM. Then on the 23rd of the month we received over 2 inches of rain and it began to look like we’d end up with well above the normal amount of precipitation for the month. On the last day of the month we received an additional 1.75 inches of rain (glad it weren’t snow!) bringing us to 6.19 inches for the month bringing us to 40.2 inches for the year to date, still 0.42 inches below normal. It’s now Tuesday morning December 1st and it’s still raining and that 0.42 inch deficit is already history, pushing us above average rainfall for the year to date. You’ll find the 2020 Precipitation chart on the Clary Dam Flow Statistics page (along with some other cool graphs). It would appear that the 2020 drought is about over. Continue reading

October 2020 Water Level Chart Archived

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October 2020

I have archived the October 2020 Water Level Chart (at left). October water levels were right about where we want them this time of year- down about a foot, more or less. Substantial rainfall around the middle of the month both signaled the end of severe drought conditions and pushed the lake level to a high of -0.77 feet below the HWM and it’s been falling gradually ever since. We started the month -1.14 feet below the HWM and ended the month higher at -0.89 feet. If you’ll recall, rainfall in September was almost nonexistent until the very end of the month. October started off with minor rain events until the 13th of the month when we received 2.44 inches in one storm. We ended up with 5.48 inches of rain for the month, 1.03 inches more than October average of 4.58 inches. Nonetheless, ground water supplies are still below normal as those of you with dug wells are well aware. As of the end of the month, our part of Maine remains in severe drought. We’re 2.01 inches below the yearly average for this date. Continue reading

September 2020 Water Level Chart Archived (edited)

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September 2020

I have archived the September 2020 Water Level Chart (at left). September water levels were characterized by a leisurely drop over the course of the month from a high of -0.89 feet at the start of the month to a low of -1.14 feet at the end. On average the water level in August was 0.3 feet (3.6 inches) lower than it was last August. The real news in September were the severe drought conditions that have persisted (and worsened) for the entire month. We started the month slightly ahead of the yearly average and received only 0.10 inches of rain on September 1st and no more rain until storms on the 28th and 30th. That’s 25 days without a drop of rain. We ended the month with a total rainfall of only 0.74 inches, fully 3.10 inches shy of the monthly average of 3.84 inches. For the year we’re 3.04 inches below average for this date. We’re heading into October with a severe deficit of rain. Hopefully that will change soon.

 

August 2020 Water Level Chart Archived

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August 2020

I have archived the August 2020 Water Level Chart (at left). August was characterized by extremely dry and and extremely hot weather which lead to considerable lake water loss due to evaporation. The anticipated influx of runoff from tropical storm Isaias at the beginning of the month never materialized, so our efforts to create a little headroom for storm water runoff only resulted in lowering the lake level two and a half inches, not that anyone noticed! From that level (-0.65 feet below the HWM) the lake level fell steadily at the rate of about 1/4 inch per day until a series of popup thunderstorms starting on August 24th brought some much needed rain to the area that helped keep the lake level from falling further. The lake ended up at -0.90 feet below the HWM. Historically, the water level in Clary would never have been this high in August. Continue reading

02 August 2020: July Water Level Chart Archived

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July 2020

I have archived the July 2020 Water Level Chart (at left). For the third month in a row we’ve managed to maintain a relatively stable water level despite mild drought conditions prevalent at the start of the month. The lake level fluctuated only 1.5 inches from low to high over the course of the month, starting out at -0.50 feet and ending the month with the lake level at -0.41 feet. A number of people have let us know that they think the lake level this summer has been about perfect. We were shy of the monthly average rainfall until two back-to-back squalls on July 30th dumped a little over an inch of rain and pushed our monthly rainfall total to 3.77 inches, a little over the average for July of 3.54 inches. Because of an extra dry June, we’re still 0.28 inches below average for this date.

Tropical storm Isaias is due to pass through Maine this coming Tuesday night into Wednesday, and it has the potential of dropping several inches of rain, if not more. We’ve temporarily increased outflows so as to create a little head space to accommodate the anticipated storm water runoff. We don’t expect any significant flooding or a major change in the water level when it’s all said and done. Continue reading

June 2020 Water Level Chart Archived

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June 2020

I have archived the June 2020 Water Level Chart (at left). For the second month in a row, the most notable thing about the chart is how relatively stable the water level was especially in light of how little rain we received! Total water level variation for the month was only 0.18 feet (2.2 inches), starting out the month at -0.37 feet below the HWM, falling to a low of -0.55 feet on the 27th, and finally ending the month a little higher at -0.50 feet below the HWM thanks to some much needed rain. Keep in mind that the HWM is actually 3 inches or so ABOVE the lowest point on the dam; for most of the month the lake was pretty much lapping at the top of the dam. We really can’t get more stable than that. Continue reading

May 2020 Water Level Chart Archived

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May 2020

I have archived the May 2020 Water Level Chart (at left). The most notable thing about May was how stable the water level was, hovering right around the top of the dam and varying only a little more than 2 inches (0.18 feet) over the course of the entire month. This was by design of course. We started the month at the low of 150.79 feet, hit a high of 150.97 feet on the 22nd, and ended the month at 150.82 feet, only a fraction of an inch higher than we started. This was by design of course: the WLO specifies that after ice out in the Spring we should raise the lake to it’s “full capacity” and keep it as close to that level as possible through the end of July. We consider the lake is at “full capacity” when the water is lapping at the top of the dam, despite the fact that the elevation of the “High Water Mark” is roughly 3 inches higher; we obviously can’t be expected to maintain a lake level where water is running over the top of the dam. Continue reading

April 2020 Water Level Chart Archived

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April 2020

I have archived the April 2020 Water Level Chart (at left). The most notable thing about April (aside from the cold weather!) was the excessive rainfall we received which resulted in a short but intense period of extreme high water. Two back-to-back storms on the 9th and the 13th dropped a total of 3.65 inches of precipitation. In addition to a good charge of rain, the first storm also included about 8 inches of very heavy wet snow which completely melted during the second weather event, which was all rain. The resulting runoff from both storms caused the lake level to rise quickly, cresting at 151.75 feet or fully 0.58 feet above the High Water Mark, by far the highest we’ve seen the lake in a long time. The last time I saw more water going over the dam was during the Patriot’s Day storm back in 2007. According to our Dam Operation Log total outflows peaked around 230 cubic feet per second. We hurriedly opened the gate all the way the day before the storm and left it open for 5 days to help drain off some water, and the lake level quickly returned to where we want it this time of year: at or very close to the top of the dam.

We received a total of 6.25 inches of precipitation in April, fully 2.38 inches more than the monthly average of 3.87 inches. This brings us to 16.14 inches for the year to date or 2.70 inches more than the average of 13.44 inches. We’ll see if this trend keeps up in May.

Here are a few pictures from the April 14th high water event:

 

04 April 2020: Clary Lake Full Once Again

20200404_114344A few days ago when I posted about archiving the March water level chart I said I expected the lake would fill soon, but that was before we received heavy rain on Thursday and Friday. That did the trick! This morning the lake had risen to an elevation of 150.96 feet and water was just beginning to flow over the top of the dam (picture at left). What a pleasant sight! While the current lake level is still 0.21 feet below the HWM, I consider the lake to be full when water is just beginning to flow over the top of the dam. Dave Knight and I went over this morning and installed the 6th and final stop log and opened the gate just a wee bit to tweak the outflows. Our goal now will be to maintain this water level (or close to it) through the end of July. The current minimum flows of 35.9 cfs drop to 8.3 cfs on May 16th.

03 April 2020: Clary Lake is Featured Lake on Lakes of Maine Website

Lake Stewards of Maine maintains several great websites including the Lakes of Maine site which provides detailed technical information about most lakes in Maine, including Clary Lake. They also feature a different Maine lake on their website every month including a picture and a brief write up about the lake. April’s Lake-of-the-Month is Clary Lake! The picture they’re using for Clary Lake was taken by David Hodsdon. Another cool site maintained by Lake Stewards of Maine is the Near Real Time Lake Data site.

 

March 2020 Water Level Chart Archived

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March 2020

I have archived the March 2020 Water Level Chart (at left) which for what it’s worth was labeled “Clary Lake Water Level February 2020” for the entire month of March due to an oversight on my part. Hope nobody was confused about what month it really was! The remarkable thing the March water level chart reflects is the relatively stable water level that lasted through the whole month, hovering right around 1 foot below the HWM for most of the month. Normally, long about the middle of March precipitation and rising temperatures cause the snow to start melting, and runoff starts to increase which usually more or less coincides with the change in minimum flows from the wintertime rate of 11.3 cfs to the springtime rate of 35.9 cfs. It’s about mid-March that we start to install some stop logs in the weir to start raising the lake level while at the same time opening the gate to produce the higher outflows required by a the change in minimum flows. This year however there wasn’t any snow to melt so that big charge of runoff that Continue reading