Does your Lake "Flip"?

[mcfatty]

I'm not sure what the technical name of it is, but in the spring and fall all the muck from the bottom comes to the surface.
Anybody know why this happens?

[pick_bikerider]

The lake here does that all the time. It is F*****g Nasty. I will deal with it though.

[mountain2wake]

I dont know if it's the same thing at your lake, but here we have an algea bloom.(spelling?).
We get a thin coat of green slime at the surface of the water. GOOD TIMES!

[kind]

our lake turns.. warm water goes down.. cold water comes up.

[howabouttheiris]

FROM LCRA.ORG

In reservoirs 100 feet or deeper, spring and summer weather create three layers of water - top, middle and bottom. The upper layer, regularly heated by hot sunny temperatures throughout long spring and summer days, can be 20 to 30 degrees warmer than the water at the bottom, which maintains a relatively constant temperature. The middle layer of water, with a median temperature range, acts as a buffer to keep the other layers from mixing.

But the arrival of fall cools the air temperature and shortens the periods of daylight. The lake's upper layer gradually cools and grows heavier. As the upper and bottom layers gradually reach equilibrium, the middle layer begins to dissipate, removing the barrier between top and bottom, "kind of like sliding a glass shelf out of a case," according to John Wedig, LCRA environmental coordinator.

The result is similar to what your economics professor warned could happen if society loses its middle class -- the upper and lower classes are thrown into a tumult. In the case of the reservoir, when the upper layer of water reaches a point where it's colder and heavier than the bottom layer, the upper layer sinks to the bottom of the lake, pushing up the bottom layer. If a blue norther happens to be blowing through, the cold winds can accelerate the process.

[Robert Harp]

[The Bug]

[LFADAM]

Man u guys have some nasty lakes. We never get algae, muck on the surface or anything

[Justin 25]

I think what's mainly happening on the lakes is what kind said, and part of it has to do with what you said The Bug.

[jlaws]

i ride in the waterway :\ dont really experience any of this

[jjaszkow]

We had first frost last night, so our lake will probably turn soon Too cold to wakeboard, and no snow for snowboarding .


Guess I'll have to go fishing.
Our's seem to turn, however I can't recall lots of junk being stirred up because of it. The fish do start biting again though after being lazy all summer.

[fish6942]

If it wasn't for the lakes turning(aka inversion), ours would freeze from the bottom up!!

[LFADAM]

fish6942, not possible (physics...4 deg Celsius water is more dense than ice)

[spyd4r]

yep, ours looks like pea soup..

[Xanadu]

i ride on the ottawa river, so...no.

[david-d]

On Lake Burton, there is an area of the lake where alot of the clay/mud from the banks mixes up with the water, and it makes the temp. of the water about 10-15 degrees colder than the rest of the lake, and turns the water brownish red. It's only in a certain cove, and it cuts off instantly. When we first drove back there the first day I had seen it, I thought it was really shallow or something; it was soo strange wakeboarding in red water

[mcfatty]

I found this....http://www.lakeforktexas.com/Pages/therm.html


Simply put, the thermocline is a thin layer of water in a lake which is sandwiched between the upper layer of water (the epilimnion) and the lower, colder layer of water (hypolimnion). During the summer months, surface water is heated by the sun and the surface temp could be 80 degrees or more. This floats over a layer of colder more denser water called the hypolimnion. Now, between these 2 layers you have a thin layer in which the water temp drops fair substantially. This will be the thermocline. The temp at this level may be high 60's and up in about the middle of spring.

Let's relate this to Lake Fork. Normally the thermocline starts to set up in May. Fishermen have been able to enjoy catching spawning bass in depths of 2'-12' during the spawn. Bass have needed the warmer water temps to spawn (lower 60's and up). Moving on into the end of May, most bass have spawned at Lake Fork. This is a time of transition for the bass. As a fisherman, you are in a post spawn mode. Crankbaits, lizards, jigs and Carolina Rigs, to name a few have worked well for spawning bass and should still continue to produce through the summer. As we move into the end of May and into June you can look for the post spawn to set in. This is generally the time the Thermocline will start to set up. When the water temps reach about 73 degrees, you can plan on predictable fishing. Plastic worms work well, crankbaits, spoons and jigs to name a few. Usually water depths between 12' to approximately 22' are the depths of choice. This is the thermocline.

In full-blown summer you will have 3 distinct water temperature changes (at these approximate depths), 0 to 12', 12' to 22', and 22' to 45'. The temperature may drop by 10 degrees at each depth. Many of you have probably heard of a lake "turning over" and this is exactly what it does. During late Autumn, (usually in October on Lake Fork) the cold winds blow as the fronts start coming through. This in turn drops the waters surface temperature. As it cools this surface water will sink to the bottom of the lake. So when cooler weather arrives the layer that was the warmest (the surface layer) displaces the lower level and the lake turns over. This movement which occurs every year allows the bottom layer to be exposed to the air allowing it to be used by living organisms. In shallow lakes with an average depth of 15 feet usually no thermocline will develop. Mother nature keeps all this in check. In such cases as very shallow lakes you may find heavy cover to screen out some of the suns penetrating rays.

October is a month of water temperature changes, once again, for Lake Fork. Depending on our weather you will find water temps becoming more uniform from the surface to about 25' in most areas of the lake. The temps may vary from 69 degrees (surface temp), to 66 degrees down to the 22' mark, give or take a few feet. Fall fishing patterns have set in and you can count on nice numbers of fish with predictable patterns. Is the hypolimnion void of oxygen? At certain times of the year this may true but there are also certain times when it has more oxygen than the other layers of water. As you already know the turnover on Lake Fork usually occurs in October. The water begins to cool. The shallow coves are among the first to cool and the bass will begin to relate to shallow structure, this is why fall fishing is fantastic at Lake Fork. Generally speaking the thermocline averages 7 to 10 feet thick and is usually found at 22' of water. The bass will be caught in the upper regions of the thermocline (early October), but usually the best fishing occurs just above where the thermocline starts.

The main thing to remember is when stratification is evident the bass will be found in greater concentrations within the thermocline. Why is this? Two reasons. First the upper layer has too much light penetration to be comfortable for the bass and the hypolimnion is usually void of oxygen. This leaves the thermocline where the light is just right and the oxygen is comfortable for the bass. Remember bass can see ultraviolet rays and do not have eyelids, their pupils do not adjust as humans do. Also remember sunlight will diffuse differently depending on the time of day. Early morning and late afternoon the suns rays will be at more of an angle and not as intense. Wind will also affect the suns penetration into the water, as will the clarity of the water. Can you catch bass in the hypolimnion? Why do anglers catch bass in 40 feet or deeper water? During the late winter there is usually no stratification on Lake Fork or most other lakes. As a result the water will undergo a temporary oxygenation process. Strong winds, feeder streams feed the lake with spring rains and plant growth begins. So under normal conditions the deeper end of a water body will be quite saturated with oxygen. Since the lower layer is much colder than the surface (averages 10 to 25 degrees difference) the deeper portions can retain the oxygen molecules sent its way during the pre-stratification. Why does the hypolimnion lose it's oxygen? The thermocline and the upper layer of water are continually replenishing their oxygen supply and the hypolimnion gradually loses it for several reasons. Probably the most important reasons are is that there is very little or no plant life beyond the 30 foot level. Unless the water is gin clear the suns rays cannot penetrate this far into Lake Fork enough to grow any vegetation.

The bottom 2 to 10 feet of a lake will also be where everything settles to decay thus eating up the oxygen. Fishermen will find Lake Fork usually has no thermocline until late spring or early summer and its this time you must understand what the thermocline is and what role it plays on fishing. Lake Fork and most all lakes will turnover in the fall. When this happens you can usually smell something that resembles the smell of rotten eggs and many times you will see particles of decaying matter in the water, this is the tale-tell sign that the lake has turned over. Some years, depending on the weather we have, the turnover will be more abrupt than others. Back in October 1994 Lake Fork experienced quite an abrupt turnover. Millions of shad were seen either dying or dead on the surface, and many fishermen reported the very strong smell of rotten eggs for a week or so. Estimates of the shad die off that year was over 12 million. Luckily though shad reproduce extremely fast and no noticeable decline in fishing occurred due to this turn over.

[Fast351]

Yeah our lake turns.

It turns pea soup green about the end of June. This is when I move to the river (flowing water = no algae).

Sometime in Sept/Oct the lake goes from green one day to not green the next. Comes from cold water coming up from the bottom (so I've been told).

[SeaLyon]

We're on the tenn river system (pickwick lake) not to much problem with that but the last few years we have been getting plant growth during the summer.

[pilot_ryder]

well we get big green stuff logs of algae that float on the water.
its gross

[dizzyj]

I live at very beginning of lake austin, which comes out of the bottom of travis, which is quite deep. Travis is turning over, and the water coming through the dam has a bit of a sulfer smell to it right now. Happens every fall.

[MinnesotaBoarder]

my lake stays clear all year long. Untill it freezes wicth will happen soon

[kyle]

my lake has crazy algae blooms once or twice a year that turns the entire lake from a dark blue (normal) to emerald green. Gives me wild allergy attacks

[SeaLyon]

It's a bummer the water is cooling of,maybe my wet suit will still fit

[Fast351]

[RC]

nope

[Mike O]

Ours turns over every spring when they refill the lake and it gets to full pool.