lake level

[jeffk]

At the end of June, the lake level was almost EXACTLY where it should have been to match the 40+ year mean targeting. I don't call that "botching" management of the high spring rain amounts. We came out of Spring right where we should have been.

Since then, there has been a dearth of rain, especially in August. We are in drought conditions. The dam output has been at the lowest possible level, 250 CFS, for all of August and since mid July. Early July was at 350 CFS with some brief bounces to 600 CFS which I would suspect was associated with maintenance efforts. For all intents, the dam has been as "shut" as much as it can be for the last 2 months.

The problem has NOT been mismanagement. The problem is NO RAIN. You can't "manage" water resources that are not delivered by mother nature.

[jeffk]

Another interesting factoid is that average rainfall in NH for July and August is 3 to 4 inches per month. The dam minimal output at 250 CFS lets about 4 inches a month flow out. So, the normal dam output for July/August would balance average rainfall. Obviously with runoff and other factors it's much more complex than this but it gives you an idea of a reasonably balanced system.

Add in evaporation effects and other lake outflows and you would see a gradual drop in lake level over the summer, which, on average, is what we normally experience.

This has NOT been an average summer.

[Geneva Point]

Sue Doe-Nym is right in my opinion. Its been mismanaged since the beginning of July regardless of having only a 10 day forecast and lack of long range data. There hasn't been any appreciable rain in the 10 day forecast for 2 months. If the dam managers had been looking at each 10 day period, like I have, they would have seen no rain each time and taken steps to maintain better water levels for this drought period.

[TomC]

There is a contractual minimum discharge rate for the dam. This outflow is a regulated 250 cubic cfs to support downstream aquatic needs and meet deeded water rights. This is where the flow has been kept now for 6-7 weeks. nothing more could have been done...

[John Mercier]

They can't go below the minimum.

So no rain in the forecast still requires the minimum outflow.

Which means the level goes down... and will continue to go down... until the forecast has more rain than the minimum output.

[jeffk]

Originally Posted by Geneva Point

... they would have seen no rain each time and taken steps to maintain better water levels for this drought period.

Ummm, if the dam output is already the lowest it can go (pretty much through all July and August), how exactly could they have done that?

Bucket brigade? Everyone visiting the lake has to bring 100 gallons of water to contribute?

[Descant]

Generally, tghe DES goal is to be full pool in early June. For me, I'd aim for full pool mid to late July. Then evaporation and 250 CFS outflow would bring us down to a reasonable level (say 6-8" below full on Labor Day, and slow release until Columbus Day. Some years ago I had a related dsiscussion with the dam bureau manager. I suggested that people are now paying substantial sume for their boiats and they have a reasonable expectation of use in the fall, after Labor Day. His response was "Oh. We never thought about that. We always think boating ends on Lablr Day."
A 10 day forecast, in my mind, is relatively meaningless. We have records going back decades and should be managing based on those averages. I think that is mostly what DES does.
On the bright side, no rtain means little surface water run off and less septic leaching. We haven't heard much about beaches closed for e coli and cyanobacteria this year.

[Sue Doe-Nym]

Originally Posted by jeffk

Ummm, if the dam output is already the lowest it can go (pretty much through all July and August), how exactly could they have done that?

Bucket brigade? Everyone visiting the lake has to bring 100 gallons of water to contribute?

Ha ha! Very amusing….but there’s no need to mock those who seriously wonder why there isn’t a better and more reliable system for regulating the water level, given advances in modern technology. It appears that the SWAG system is the one currently in place.

[secondcurve]

Originally Posted by Sue Doe-Nym

Ha ha! Very amusing….but there’s no need to mock those who seriously wonder why there isn’t a better and more reliable system for regulating the water level, given advances in modern technology. It appears that the SWAG system is the one currently in place.

There isn't. Short of building a new reservoir.

[Sue Doe-Nym]

Okay…. I am not happy with the consensus, but I surrender! It’s hard to believe that we need to rely on what seems to be archaic stuff, but hopefully something better will surface in the future. Here’s to higher lake levels! 👏🏼👍

[ApS]

Originally Posted by Sue Doe-Nym

Okay…. I am not happy with the consensus, but I surrender! It’s hard to believe that we need to rely on what seems to be archaic stuff, but hopefully something better will surface in the future. Here’s to higher lake levels! 👏🏼👍

Over the last three decades, I've been following the slow progression of a group of my neighbor's large trees. Every June, pictures are taken.

Five of the seven are still standing, but hanging over the lake. Two maples couldn't support the angle they'd been forced to maintain and snapped off. As collapsed trees deteriorate, all of the chemical compounds in those trees are slowly leaching into the lake. (Enriching algae).

So what is happening?

High lake levels don't stop at the boulders lining the lake. Surface waters reach far under many miles of the lake's waterfront properties. Winter's precipitations move undesirable nutrients closer to the lake. Wakes intensify that movement and flush high-nutrient soil compounds into the lake. (Nitrogen, phosphorus, aluminum).

My acre of lakefront has lost countless trees. Two, with a circumference of twelve feet, have fallen in within the last decade. Two others continue to grow, but are likely to fall the next decade.

Admiring a new gutter installation, I leaned against a large pine. Because it was a windy day, I was surprised at how much it moved. Unseen, its roots were moving as well. While such movement exposes new nutrients for the tree, it also shuffles underground soils. Gravity moves such soils closer to the lake.

In short, hillsides are sliding into the lake. After Ice-Out, oversized boat wakes assure this endless slide.

Higher levels harm the lake.

[jeffk]

Originally Posted by Sue Doe-Nym

Ha ha! Very amusing….but there’s no need to mock those who seriously wonder why there isn’t a better and more reliable system for regulating the water level, given advances in modern technology. It appears that the SWAG system is the one currently in place.

I find it amusing that people speculate about weather forecasting or other technology that could manage the water level better. There are constraints on the management of the lake level that cannot be overcome without absurd levels of effort and expense or damaging results because of the attempt.

First, the amount of water coming into the lake is controlled by snow melt and rain. We are at the mercy of the weather.

The amount of water removed from the lake occurs through numerous runoffs and evaporation. The only control on this process is the Lakeport dam. Water cannot be stored up in the lake beyond a certain point without doing damage. So even if we looked ahead for 2 months and saw a drought, we could only hang on to only so much extra water. Further, once the dam output is at 250 CFS we CANNOT go lower, as noted in other comments. That still drops the lake by about 4 inches per month.

There is a 40+ year history of the mean lake level and DES manages the level to approximate that mean. There are numerous reasons for that. For example, the level is dropped in the Fall and Winter to allow for management of snow melt and Spring rains. The lake is allowed to “fill up” until mid-June to allow for summer activities.

Here is a summary of what happened this year.

~June 15 is targeted to be Full Pool. The mean level drops from this point on.

On June 18 we had Full Pool, close to the target. The dam output was 1000 CFS.

On June 23, dam output dropped to 600 CFS.

On June 26, dam output dropped to 350 CFS.

Within 10 days, June 18 – June 26, the dam output was dialed back to almost minimum.

On July 15, dam output dropped to 250 CFS, the minimum possible.

The lake level on July 15 was only 1” below the 40 years mean. That seems to be pretty reasonable. Further, since the dam was at minimum output, THERE WAS NOTHING FURTHER THAT COULD BE DONE TO RAISE THE LAKE LEVEL, even if we knew for sure what the weather was going to do.

The result seems to blame the DES for “mismanagement” and to curse the weather Gods.

The mean level of the lake normally drops about 10.5” from Full Pool by now. We are down another 7.5” entirely due to lack of rain through July and August. The dam output has been minimum all that time. Even if given foreknowledge of no rain, there is nothing else we could have done.

If we had retained 7” of water from the Spring rains, we would have had NO WAKE conditions on the lake which comes with its own set of problems and damage. There is no forecasting technology that can be accurate for two months ahead so we can not know.

If someone can state specific solutions that could/should be applied, do so. I don’t see any. We are nowhere near forecasts that can go out all summer. The dam was managed to reasonable standards based on existing constraints. The weather has caused lake levels to approach the most extreme results in 43 years (there has been worse). The results are what they are, even if they create difficulties.

Griping and blaming doesn't solve problems and some problems are not solvable.

[Descant]

I agree with Jeff K to a point. The goal for full pond should be mid-to late July, not mid-June. However, comparing the level to a mean from the past instead of to a current goal is where I believe the problem lies. Ther is rarfely a reason to go to outflow of 1000 cfs in June since all the downstream needs are already met by snow melt and spring rain. Once in awhile there is a late June thgunderstorm that drops a lot of water. Fine, but there isz no reason at that point that we can't go 0.5""-1.5" above full pond. When we go lake wide No Wake, it is much higher thanm that.

In sum, the mistake is in comparing levels to an old mean instead of to a current, new goal.

[secondcurve]

Originally Posted by Descant

I agree with Jeff K to a point. The goal for full pond should be mid-to late July, not mid-June. However, comparing the level to a mean from the past instead of to a current goal is where I believe the problem lies. Ther is rarfely a reason to go to outflow of 1000 cfs in June since all the downstream needs are already met by snow melt and spring rain. Once in awhile there is a late June thgunderstorm that drops a lot of water. Fine, but there isz no reason at that point that we can't go 0.5""-1.5" above full pond. When we go lake wide No Wake, it is much higher thanm that.

In sum, the mistake is in comparing levels to an old mean instead of to a current, new goal.

So your solution is to squeeze in another 1/2 inch to 1 1/2 inch at the full level. Ok. Maybe that’s possible I don’t know but even if is possible would that really make a difference today? I don’t think so. Any other ideas?

[TomC]

Find out why/where that minimum outflow of 250 cfs goes and if it still has relevance. If there is an economic need (I have a possibly faulty memory that its to ensure sufficient power generation to someone) - then whoever has this deeded flow rate could be compensated by the state, or a small shoreline town tax, voluntary contribution, or some other subsidy. Then the dam could be closed and if the 4"/month drop rate at 250 cfs is accurate, the lake would have 6"-8" more water in it with all other things being equal...

[John Mercier]

Originally Posted by TomC

Find out why/where that minimum outflow of 250 cfs goes and if it still has relevance. If there is an economic need (I have a possibly faulty memory that its to ensure sufficient power generation to someone) - then whoever has this deeded flow rate could be compensated by the state, or a small shoreline town tax, voluntary contribution, or some other subsidy. Then the dam could be closed and if the 4"/month drop rate at 250 cfs is accurate, the lake would have 6"-8" more water in it with all other things being equal...

Opechee, Winnisquam, Silver Lake, and then to Franklin before merging with the Pemi to become the Merrimack.

[BillTex]

Originally Posted by Geneva Point

Sue Doe-Nym is right in my opinion. Its been mismanaged since the beginning of July regardless of having only a 10 day forecast and lack of long range data. There hasn't been any appreciable rain in the 10 day forecast for 2 months. If the dam managers had been looking at each 10 day period, like I have, they would have seen no rain each time and taken steps to maintain better water levels for this drought period.

We are not on Winni, but on another nearby dam controlled lake. We are not (so far) having any of these issues.