Category Archives: Technical Lake Stuff

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

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 →

February 2020 Water Level Chart Archived

February 2020

I have archived the February 2020 Water Level Chart (at left). The lake level was pretty sedate for most of the month, falling slowly and steadily from a high of -1.09 feet at the beginning of the month to a low of -1.52 feet on the 27th. On that date we received an inch of rain which melted a good deal of our snow pack and brought the lake up almost half a foot by the end of the month.

That last rain event brought our monthly precipitation total to 3.19 inches, 0.58 inches more than the February average of 2.61 inches. For the year to date we’re already 0.39 inches above average. The dam’s control structures (weir and gate) remained unchanged for the whole month with the gate open about 4″ and no stop logs in the weir. Minimum flows will rise from the current 11.3 cfs to 35.9 cfs on March 15th at which time we’ll open the gate some more to provide the increased outflows, and will probably start adding stop logs to the weir to start raising the lake level to normal spring levels. Continue reading →

January 2020 Water Level Chart Archived

January 2020

I have archived the January 2020 Water Level Chart (at left). Not a lot to say about this chart! The lake level remained a little higher than we want it this time of year, but not outrageously so. We’ve been trying to keep it down around -1.50 to -1.75 feet below the high water mark; the actual level has fluctuated from a low of -1.52 feet and a high of -1.09 feet, a range of only 0.43 feet. We received 3.00 inches of precipitation, a little shy of the average for January of 3.19 inches. Much of the precipitation was in the form of rain. Not a lot of snow out there.

02 January 2020: The Winter 2019 Water Column Issue Is Out

The Winter 2019 Lake Stewards of Maine’s periodical “The Water Column” arrived in our mailbox today. As usual, it’s full of interesting information about the state of lake water quality monitoring in Maine, invasive plant problems around the State, and other issues impacting lakes in Maine.

Last year’s Winter 2018-2019 issue of The Water Column was all about the impact of climate change on Maine lakes, and this winter’s issue continues their coverage of climate change with an interesting article on ice-in and ice-out trends. The Lake Stewards of Maine does a great job of publicizing their activities. The Clary Lake Association has been conducting water quality monitoring on Clary Lake in association with the Lake Stewards of Maine (formerly the Volunteer Lake Monitor Program or VLMP) since 1975 and is a long time supporting member of their organization.

https://www.lakestewardsofmaine.org/mediaresources/the-water-column/

Here’s a link to the full document:

The Water Column Winter 2019

December 2019 Water Level Chart Archived

December 2019

And 2019 is a wrap! I have archived the December 2019 Water Level Chart (at left). The most interesting thing about the December chart is once again, how much precipitation we received. It’s been a wet year and December was no exception. It still amazes me how much water can flow into- and out of- Clary Lake in a relatively short period of time. More on that later. In addition to the monthly chart I’ve also archived a bunch of other charts including the 2019 whole-year chart, the 2019 flows chart, the 2019 precipitation chart, and by the time I’m done probably a few more charts as well. You’ll find ALL of them in the 2019 Water Level Charts archive. I love charts. Does it show? Continue reading →

17 December 2019: Clary Iced-In For The 3rd Time! [UPDATED]

Clary Lake has had a hard time staying frozen this year! It initially completely froze over on December 4th and remained well frozen for a week. Then warm temperatures and heavy rains caused it to mostly open up again on December 11th. It had completely refrozen by the next day December 12th, only to completely melt off again on December 15th! This morning, as you can see on the composite photograph of the 3 Clary Webcams, it appears completely refrozen with the possible exception of a small sliver of open water over on the east end of the lake. This afternoon’s expected snow fall will show if that’s really the case. Perhaps this is it. I don’t see anything in the forecast to suggest the lake will melt off again, but you never know.

While December 4th is early for ice in, historically it’s not particularly early at all. I recall as a kid ice skating on Clary Lake at Thanksgiving. Visit our Ice-In and Ice-out dates for Clary Lake page. We have records available back to 2001.

[UPDATE] I guess I wouldn’t be calling the lake fully frozen just yet, judging from the amount of water that’s leaking up onto the surface. When it first started snowing today, dozens of small wet spots appeared. As the snow continued, the wet spots grew in size and number. There must be small holes in the ice for this to occur. Perhaps a good hard freeze will finish the ice-in process!

November 2019 Water Level Chart Archived

I have archived the November 2019 Water Level Chart (at left). The most notable thing the November chart shows is nothing much! We got a lot of rain (3.75 inches), but not as much as in a normal November (4.58 inches), the month with the highest rainfall on average. We were hoping to keep the lake level around 1 foot below the HWM without overspending our water budget and we did mostly OK until a series of rain storms in the latter half of the month brought the lake level back up to within less than 1/2 foot of the top of the dam. Rather than overspend our water budget, we ended up with water in the bank so to speak. Not really a problem, but not what we were looking for. We ended the month only a 10th of a foot or so lower that we started. We’re currently letting out close to 60 cfs in an attempt to drop the lake to a more normal level for this season. Continue reading →

October 2019 Water Level Chart Archived

October 2019

I have archived the October 2019 Water Level Chart (at left). The most notable thing the October chart shows is Holy Hannah did we get a lot of rain 🙂 We started the month 0.85 inches BELOW average and ended the month just shy of 3 inches ABOVE average for this date. All told we received 8.28 inches of rain in October whereas average rainfall for October is a “only” 4.45 inches. We received almost twice that. We’re now at 39.02 inches for the year, just 5 inches shy of what we’d expect to receive for the whole year, and we still have 2 months to go (see Precipitation chart below). All that rain complicated our efforts to draw the lake down this fall, and currently the water level sits at around 0.60 feet below the HWM, give or take- a level more appropriate for mid to late Summer. Continue reading →

15 October 2019: CLA’s Water Quality Monitoring Team Wraps Up Another Season

We’ve wrapped up another season of water quality monitoring on Clary Lake and took this selfie to celebrate. For David Hodsdon, this completes his 44th year of water quality monitoring (he started in 1975!). For Kelsie French it is her second, and for me, my sixth. Jack Holland also helps out when he can. I think he’s been doing it for close to 20 years. We’ve got a good team doing good work.

Clary’s water quality this past summer was better than what we’ve come to expect in recent years despite a mid-summer high Phosphorus reading of 0.028 mg/liter (the 4th highest we’ve ever recorded). That’s considerably higher than we’d like to see it. The high P sample was likely attributable to the 15″ of rainfall we received in April, May, and June as runoff from rainfall is the primary source for Phosphorus. We did see a small burst of cyanobacteria growth no doubt in response to the high P in the lake water, but it dissipated quickly and didn’t raise any real concerns. The results of our last Phosphorus sample (we take 3 samples per season) taken on September 27th) aren’t back from the lab yet. We’re hoping it shows improvement.

Clary Transparency

The average of 13 transparency readings over the summer was 3.6 meters (11.8 feet) which for Clary is Great! Transparency never fell below 3.15 meters (10.3 feet) and got as high as 4.20 meters (13.8 feet) in early May. You can see on the chart of secchi disk readings at left that overall transparency in 2019 easily bucked the historical downward trend we’ve seen during the years of our water level crisis. We expect our newly restored water level regime will result in good water quality going forward, but we’ve got to remain vigilant. Lakes are fragile ecosystems and many issues can affect water quality.

Here’s a link to our water quality monitoring data going back to the beginning of 2012. Historical data is available upon request:

Clary Lake Water Monitoring Data

September 2019 Water Level Chart Archived

September 2019

I have archived the September 2019 Water Level Chart (at left). The most notable thing the September chart shows is how dry it’s been! We received only 1.97 inches of rain, just a little over 1/2 the September normal rainfall of 3.84 inches. As of the end of August we were 1 inch above normal rainfall, but the lack of rainfall in September means we’re now 0.85 inches BELOW normal for this date. Hopefully precipitation will pick up later this fall.

Despite the lack of rainfall in September, the lake level remained well within our target range of -0.50 to -1.0 feet below the HWM (high water mark) while maintaining the required minimum flows. We attribute this relative lake level stability to our management practices (as described in our Water Level Management Plan) and the repairs we performed last Fall which have reduced leaks to a minimum. Per our plan, we will continue to gradually lower the lake level in October to between 1 and 1.5 feet below the high water mark, and we expect to reach the maximum draw down of approximately 2 feet below the HWM by the end of November where it will remain until early Spring.

18 September 2019: Maine Public Radio Program on Algal Blooms

Scott Williams of Lake Stewards of Maine

There is a new Maine Public program on algal blooms and climate change that is well worth watching (or listening to). Here on Clary we have avoided a severe algal bloom this season though we’ve seen them in the past; we did have a mild, short-lived bloom back in early July, no doubt brought on by a spike in phosphorus levels due to heavy rainfall and the resulting runoff in April, May, and June. While Phosphorus levels have remained high this summer, transparency has remained greater than 3 meters all season. We’ve been fortunate. We are most at risk however in September and October as the lake water “turns over” mixing phosphorus at the bottom of the lake into the upper layers of water where it can feed blue-green algae.

Maine Lakes Expected to see More Intense Algal Blooms

August 2019 Water Level Chart Archived

August 2019

I have archived the August 2019 Water Level Chart (at left). The most notable thing about this chart is how much rain we received during what has traditionally been the driest month of the year. August started out dry, but it wasn’t long before we broke the Summer drought trend started in July. We received a total of 3.70 inches or 0.37 inches more than the average for August. This rainfall helped keep the lake level right about where we wanted it all month. For the year to date we’re 1 inch above average.

Minimum flows for the period from July 1st until September 15th are 1.9 cfs (cubic feet per second) which is about how much leaks through the dam. Minimum flows rise to 3.5 cfs on September 16th. The minimum flows vary throughout the year as follows:

11.3 cfs between January 1 and March 15;
35.9 between March 16 and May 15;
8.3 cfs between May 16 and June 30;
1.9 cfs between July 1 and September 15;
3.5 cfs between September 16 and November 15; and
15.5 cfs between November 16 and December 31.

I’m still tweaking the monthly water level chart from time to time, but don’t expect major changes. I like this one.

July 2019 Water Level Chart Archived

July 2019

I have archived the July 2019 Water Level Chart (at left). The most notable thing about this chart is it shows rainfall fell off a cliff in July with only 2.39 inches being recorded for the month, over an inch less than the average of 3.54 inches for July. The latter part of the month has been driest: we’ve only received 0.16 inches of rain since July 13th. That said, due to the above-average rainfall received in April, May, and June, we’re still 0.65 inches above the yearly average for this date. While we’re not in official drought territory yet, we will be soon if this dearth of rainfall continues.

The lake level has fallen since the first of the month, starting out 0.13 feet above the HWM and ending the month 0.32 feet below the HWM, a total range of only 0.45 feet. Still, despite the lack of rain, the lake level is higher now than it historically would be on this date; water was still flowing over the top of the dam until just a few days ago. We’ve only been able to maintain this high water level because of the dam repairs we made late last fall which has reduced leaks to a just a few cubic feet per second, which conveniently supplies the minimum flows (1.9 cfs) for this time of year. We anticipate the lake level will continue to fall an additional 6-8 inches through the month of August, depending on rainfall. Continue reading →

05 July 2019: Moderate Algae Bloom in Progress

Cyanobacteria coloring the water.

You may have noticed a green scum drifting on the lake surface recently or seen loads of green particles suspended in the water and thought it was pollen. Well, it does look a lot like the pine pollen that was blowing around last week, but that was yellow, and this stuff is green. Clary Lake is actually experiencing moderate blue-green algae growth resulting in an algal bloom. This early season algae bloom has no doubt been fueled by excessive runoff from all the rain this spring (15″ since the 1st of April!) which has introduced Phosphorus and other nutrients into the lake. Phosphorous is the primary food for plants and algae. Blue-green algae technically is a phylum of bacteria (cyanobacteria) that obtain their energy through photosynthesis. Another likely source of Phosphorus is rotting terrestrial vegetation. For years, better than 300 acres of drained wetlands have been growing grass, goldenrod, alders, and other terrestrial plants and that land is now under water, and the vegetation is rotting. This releases nutrients including Phosphorus in the water, helping to fuel aquatic plant and algae growth. Here are a few more photographs:

[Show slideshow]

All this rainfall has also resulted in significant flushing of Clary Lake, well in excess of normal. Since January 1st, the lake’s entire volume of water (7,224 acre-feet) has been replaced almost twice. The inverse of the flushing rate is retention time (how long water stays in the lake) and that figure has decreased to about 92 days. The published “flushing rate” for Clary Lake is 1.81 times per year. We’re going to exceed that value by a significant amount. This will help “wash out” the nutrients currently in the lake, but will also result in more nutrients being brought into the lake. This is why controlling non-point sources of soil erosion and sedimentation is So Important: it doesn’t help replacing nutrient-laden water with more nutrient-laden water.

I expect this current algal bloom to dissipate soon, and it remains to be seen if we’ll have additional algae growth this year. Under the circumstances, I wouldn’t be surprised. It is important to remember that even though the dam has been repaired and the lake level restored, the ecology of Clary Lake has been severely damaged as a result of the 8 years of low water and it going to take some time to recover. Clary is still at-risk from both natural and man-caused issues and deserves our ongoing attention.

June 2019 Water Level Chart Archived

I have archived the June 2019 Water Level Chart (at left). The most notable thing about this chart is that it shows we received 6.72″ of rain in June which has got to a record of some sort. As a result, the lake level has remained very close to or slightly above the HWM elevation of 151.17 feet with water flowing over the top of the dam for the entire month. In fact, water has been flowing over the top of the dam since April 1st, which is quite unusual. Average rainfall for June is “only” 3.73 inches and we exceeded that amount by almost exactly 3 inches. This puts us going into summer 1.8 inches ahead of average precipitation for this date. We expect the lake level to gradually drop over the next 2 months, assuming precipitation returns to something more like normal.

Minimum Flows drop today to 1.9 cubic feet per second (cfs), the lowest outflow rate of the year. Outflows will remain at this level through September 15th when they go up to 3.5 cfs.

I’m liking the new water level chart pictured above. What I like most about it is I’ve spent exactly NO TIME uploading daily updates as the charts are generated dynamically by Google. That said, I’m still tweaking the design.

May 2019 Water Level Chart Archived

May 2019

I have archived the May 2019 Water Level Chart (at left). The most notable thing about this chart is that it shows the lake level hovered around the Normal High Water Mark for the entire month, something that hasn’t happened since last month 🙂 More to the point, this is the last in this hand-made series of water level charts that I’ll be producing. I’ve been threatening to stop making these charts for a while, but old habits are hard to break. This time I’m really done. I started 8 years ago in January 2012 at the start of our long water level crisis. The introduction of the new Dam Operation Log however with its own automatically generated charts and graphs has made these traditional charts a duplicated (and wasted) effort. I have better things to do now and I just can’t justify the time and effort to continue making them. Since starting recording water level measurements in December 2011, I’ve made 2700 individual water level measurements and posted 101 Monthly water level charts. It’s the end of an era, and about time!

The Current Water Level Charts page will remain but with a new look and sporting new automatically-generated charts and graphs from the Dam Operations Log.

Finally, it was a wet month. We received 3.88 inches of rain for the month, slightly more than the average for May. For the year at 15.96″ which is right about where we’re supposed to be.

24 May 2019: CLA To Conduct Courtesy Boat Inspections

HYDRILLA (Hydrilla verticillata)

With the State boat launch back in service, our concerns rightly turn to protecting Clary Lake from the chance introduction of invasive aquatic plant species. To that end, the Clary Lake Association is gearing up to start participating in Maine’s Courtesy Boat Inspection (CBI) program starting this summer, and we’re going to need volunteers! While there are various ways invasive plants can make it into lakes, by far the most common transport mechanism is on boats and trailers. Sadly, there are a number of lakes in the State with an invasive aquatic plant problem including several nearby lakes. The goal will be to have enough people lined up and trained so that the boat launch can be covered during the weekends to inspect boats and trailers before they they put in the lake, to make sure there are no invasive plants hitching a ride. Continue reading →

01 May 2019: DEP Approves Water Level Management Plan

We have received provisional approval of our Water Level Management Plan [WLMP] from the Maine Department of Environmental Protection. The WLMP details the procedures we’ll be following to operate the Clary Lake dam and manage the water level so as to remain in compliance with the Clary Lake Water Level Order [WLO]. The completion of a management plan was the final requirement of the WLO and it’s good to have this task behind us. This first season is like a shakedown cruise: we’ll be sitting down with DEP staff next winter to review the plan to see how well it’s met everyone’s needs. Continue reading →

April 2019 Water Level Chart Archived

April 2019

I have archived the April 2019 Water Level Chart (at left). The most notable thing about this chart is that it shows the lake level rose up to the High Water Mark (HWM) on the first day of the month, for the first time since before our water level crisis started back in 2011! The lake level has been hovering right around the HWM for the entire month, spending some time above and some time below it, rising as high as 3 inches above the HWM on April 27th before dropping to end the month 1.80 inches above the HWM. A lake level slightly above the HWM is a more or less normal condition this time of year, and there has been water flowing over the top of the Clary Lake dam for the entire month. When the spring runoff ends (it’s already peaked), the lake level will drop back to a more reasonable level 4 to 6 inches below the HWM. The plan is try and keep it around that level through July and into August. Welcome to the New Normal. Continue reading →