From time to time I like to highlight different lake phenomena, and today’s high winds and waves are a great opportunity to discuss Langmuir Circulation. The waves today are really stirring up the water, it’s brown and quite turbid and there are long lines of white froth on the water aligned with the wind direction. I’m sure you’ve seen this phenomena before. You can see those lines of froth in the webcam picture at left. Sitting here in my upstairs home office and looking out the window down at the lake, those lines of white froth are very evident. Continue reading
Category Archives: Technical Lake Stuff
September 2021 Water Level Chart Archived
I have archived the September 2021 Water Level Chart (at left). September was on track for being an average, ho-hum kind of month with more or less normal rainfall (for a change!) and a stable unchanging water level until the 27th when we received a whopping 4.5 inches of rain in one storm. This sounds like a lot, and it was a lot, but it only brought the lake up 0.89 feet, from -1.02 feet below the HWM to just -0.13 feet below it. While this sounds like a lot, it’s actually a runoff multiplier of only 2.4X and considering how much rain we’ve had this summer, I expected the lake to have come up a lot more. By all rights we should have had water pouring over the full width of the dam but in fact we just had a wee bit dribbling over the top in a few spots. I won’t say I was disappointed, but I was surprised! The old rule of thumb is that an inch of rain should bring the lake up 4″ (a 4X multiplier) and if that rule had held true, the lake would have risen 18 inches instead of only 10 inches. For that matter, we’ve actually seen runoff multipliers considerably larger than 4X in the past. Continue reading
September 2021 Water Quality Update
Total Phosphorus Chart
The Total Phosphorus test results from our 8/6/2021 core water sample came back the other day at 0.035 mg/liter, the highest TP value we’ve ever recorded. This is ominous. The next highest value we recorded was 0.034 mg/liter in July 2007 (see chart at left). I don’t remember the particular circumstances surrounding that reading, but there was another high TP reading of 0.032 mg/l more recently, in July 2015 that I do remember. It coincided with a secchi disk reading of only 1.95 meters indicating an algae bloom was in progress (secchi disk readings of 2 meters and below indicate a bloom in progress). You can see this 1.95 meter data point on the chart showing Clary transparency below. In this particular case, extreme low water conditions were a major contributing factor to poor water quality!! I expected a high TP value this time because of the 9″ of rain received in July. Rain means runoff and runoff means soil erosion and sedimentation which is the primary source of Phosphorus in lakes, but still, I was surprised to see such a high number. High phosphorus levels are not good for water quality! We really need to update our Watershed Survey!
Despite the high phosphorus level, we haven’t seen a significant algae bloom yet this summer and we may not, though I did notice a few wisps of dead cyanobacteria along the shoreline back in August, and water transparency is currently holding up nicely: at our last the water monitoring session on Sunday September 5th, Kelsie French and I had secchi disk readings of 3.55 and 3.45 meters respectively which is about average, and better than expected considering the level of phosphorus in the water. Transparency could deteriorate quickly however and we’re going to keep a close eye on it; we will take our 3rd and final water sample for Phosphorus testing during our next water quality monitoring session in a couple of weeks. Continue reading
August 2021 Water Level Chart Archived
August 2021
I have archived the August 2021 Water Level Chart (at left). The 3.08 inches of rain we received in August fell slightly short of the 3.33 inch average for the month, so we’re a little further behind (-1.58 inches) for the year than we were at the end of July. We’ve received 26.17 inches of rain to date, the average for the end of August is 27.75 inches. We also anticipated a good soaking as the remnants of Hurricane Fred and Hurricane Henri passed by within a few days of each other and on August 19th and we opened the dam’s gate a foot to release some water and create some headspace for what potentially could have been a lot of storm water runoff. The storms were a disappointment however, dropping only a combined total of 0.84 inches of rain with virtually no additional runoff and we ended up closing the gate 5 days after opening it, having lowered the lake a grand total of only 3.4 inches. Now it looks like Hurricane Ida which will be passing to our south later this week may result in significant rainfall. Time will tell. Continue reading
12 August 2021: Damariscotta Lake Blooms
Damariscotta Lake has been experiencing considerable cyanobacteria growth in recent years, a troubling condition that affects many lakes in Maine. Some lakes are big enough for these types of events to impact only certain areas, though they can be lake-wide. This particular algal bloom in Damariscotta is in the Mills area. So far this summer I’ve noticed only slightly elevated levels of blue-green algae (cyanobacteria) in Clary as evidenced by faint wisps of dead algae on the water surface and slightly reduced transparency in early August. This is most likely the result of runoff from heavy rains in July. A small amount of algae growth is expected, and is more or less normal. Clary Lake however is by no means immune to severe algae blooms, defined as a transparency of 2 meters or less and while we haven’t experienced a severe bloom since 2014 (see chart at left), it can and will under the right condition happen again. It behooves us to be vigilant and minimize soil erosion on our properties to stop the introduction of sediment and phosphorus into our lake.
The Midcoast Conservancy staffer Patricia Nease who is monitoring the Damariscotta Lake bloom spoke at our recent Annual Meeting about the Invasive Plant Patrol program on Damariscotta Lake and things we should consider when starting up an IPP program on Clary Lake.
July 2021 Water Level Chart Archived
July 2021
I have archived the July 2021 Water Level Chart (at left). And just like that, the drought was over. The dry conditions that have plagued us since the beginning of the year have been effectively wiped out in one month due to the exceptional amount of rainfall we received in July. At the beginning of the month we were 6.78 inches shy of rainfall for the year. Then over the course of the month we received a total of 9 inches of rain! As of the end of the month we’re shy only 1.33 inches of the average of 24.42 inches for this date. Of course, there’s no guarantee that the drought will stay gone, but at least for now we can relax. It does appear that mid-to-late summer and fall drought conditions are the new normal. Time will tell. Continue reading
10 July 2021: Hurricane Elsa Delivers Much Needed Rain [UPDATED]
July 2021 Precipitation as of 7-10-21
On its way up the New England coast yesterday, Hurricane Elsa dropped over 3″ of rain on Clary Lake. While this won’t end our drought, it will go a long ways towards replenishing ground water supplies, and it brought the lake up enough for water to flow over the top of the dam again. For the month of July we’re now at 5.35 inches, well above the average of 3.54 inches. For the year we’re now only (only?) 4.97 inches short of normal for this date.
[UPDATE]: As of this morning and for the FIRST TIME this year, the lake level is +0.08 feet ABOVE the High Water Mark having risen 7.08 inches since yesterday morning. Plenty of water flowing over the top of the dam as the picture at left shows. What a treat to have such high water this time of year!
June 2021 Water Level Chart Archived
June 2021
I have archived the June 2021 Water Level Chart (at left). The drought deepens. We were shy 5.20 inches of rainfall at the end of May, now we’re shy 6.76 inches of rainfall at the end of June. We received a total of only 2.15 inches of rain in June, fully 1.58 inches less than normal. This brings us to 14.1 inches for the year to date. Our drought is nowhere near as severe as they’re experiencing in the western half of our country and especially in the southwest, but that is small consolation: this deficit will have a profound impact on our environment and ground water supplies for the rest of the year, and it’s not over. It’s so dry that even when we received a significant rainfall of 0.99 inches on the 22nd of June, the lake level only came up 1/3 of an inch. Lesser rainfall amounts during the month had almost no measurable effect on the lake level. There are two reasons for this: The primary explanation is that the ground around the lake is so dry that when the lake receives rain, the rising water is quickly wicked off into the surrounding dry shoreline. The other reason is that at this lake elevation, adding more water to the lake mostly makes the lake bigger, not deeper. Continue reading
May 2021 Water Level Chart Archived
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
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
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
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
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
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
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
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)
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.