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Thread: Water evaporation...

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    TizMe's Avatar
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    Water evaporation...

    At this point in the season should the water evaporation from an AG pool seem to be faster than normal The reason I ask is because it seems like it was only a few days ago I had topped of the water level because we were getting ready to close the pool up for the year and at the time did not get around to it. I cant for the life of me remember what night or how long ago this was .... it seems like it was only yesterday though. What other method is there to check for a liner leak other than th bucket on the steps because we have already removed them from the water and stored them for the season Its hard to tell if there is any "wet areas" around the pool because of all the pop up showers we keep having .... Could I mark the skimmer with something fill up the pool and see how long it takes for it to go back to that level again

    I would hate to think I have a leak now
    Les
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    JasonLion's Avatar
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    In many parts of the country, anywhere that it is humid over the summer, there is far more evaporation in the fall than during the summer. In Maryland I lost perhaps two or three inchs of water in the entire month of August, while I have already lost that much in October and it is only the 10th.
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    TizMe's Avatar
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    Is this something I need to be worried about or just consider it evaporation?
    Les
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    JasonLion's Avatar
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    When you have more experience with the pool it will be fairly obvious, is this year the same as last year, if not there might be a problem.

    If your humidity has been high all summer and is now low then it is almost sure to be evaporation. However the only way to be sure is to do a bucket test, or something similar. If you put a bucket of water in the pool with the same water level as the pool then evaporation will affect the pool and the bucket very nearly the same. If there is a leak the pool will go down noticably faster than the bucket. If it is evaporation they will stay about the same.
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    TizMe's Avatar
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    Funny you should ask that, this time last year the pool was buttoned up tight and closed so I have nothing to compare it with. Could it drop 3 inches in 1 week normally if it was due to evaporation? Like I say it just surprised me this morning it was that low since it doesnt seem all that long ago it was topped off.
    Les
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    According to this map from this web page, the annual evaporation rate in Georgia is 55" so that's 55/365 = 0.15" per day average over the year. Some people have reported that summer evaporation rates are about double this rate -- essentially meaning that over the winter there is minimal evaporation. So that would mean 0.30" per day or about 2" per week. Your report of 3" per week does seem to be on the high side so perhaps you should do a bucket test to see if you have a leak. Fill a bucket with pool water, mark the level, note the level in the pool, turn off any fill water refill valve to the pool, then wait several days and measure the level in the bucket and the pool. If they the pool level has dropped significantly more (and I assume the pool isn't used so there is no splash-out), then you probably have a slow leak.

    As Jason said, humidity affects evaporation rates so its possible that what you are seeing is normal, but the bucket test might help determine what's really going on.

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    TizMe's Avatar
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    Ok, will do a bucket test and let you know the results ......
    Les
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    Is there any way to cover the pool temporarily for 1 week, if you still get the 3inches then you definitely have a leak.
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    TizMe's Avatar
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    JCJR,

    We were trying to cover it for the winter and we had topped off the water so we could add the bleach, run the filter and vaccuum it for the last time and we never got around to adding the bleach etc. I went out this morning to check the filter basket for leaves and such as we have 2 HUGE Oak trees we were trying to get down before the yearly leaf dropping started and it didnt happen .... anyway... I was caught off guard/surprised at how low the water had dropped since we did the top off .... but .... of course I cant remember if its been 1 week, 10 days or longer since we did the fill and I guess I am just being overly cautious of a leak ....
    Les
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    TizMe's Avatar
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    Well .... the other night after posting here when I got home I went to the pool to start the "bucket test" and we had left the fill hose we use in the water. Its a long story but this hose runs from the house and up a set of stairs to a higher elevation then over to the pool. When we are filling it I keep noticing water dripping at the spot where the two lengths of hose connect. I also had noticed that when its off the hose still leaks ... is it possible that the leak when its off is pool water running back out of the hose and dripping where the two hoses connect We are still doing the test to confirm or NOT confirm a liner leak
    Les
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    From your description, it doesn't appear that any part of the fill hose is below the pool water level. If that's the case, the fill hose should not be "sucking" water out of the pool when the faucet is off.

    In other words, if where the two hoses connect is below the pool water level, you could be draining the pool to that elevation.
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    TizMe's Avatar
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    KT,

    The elevation change between the faucet on the house and where the pool sits (where the hose is put into the pool to fill it) is probably 6 - 8 feet ( educated guess). So theoretically the water could be running back out of the pool and because the faucet is off at the house and with the pressure change, leaking where the two lengths of hose connect ? If it would help, I could take a picture when I get home and post it here so you will better understand the elevation change between the two ....
    Les
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    ktdave's Avatar
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    A picture could help.

    All that needs to happen for the hose to siphon water out of your pool is a leak or other "opening" (such as the leaky joint where the two hoses meet) to be below the elevation where the surface of your pool water is.

    An easy check for this is to pull the hose out of the pool and monitor any water loss, say after 24 hrs or so. Compare that with the water loss you were experiencing before.
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