Evaporation?

[Cdtipton]

Hello I have an inground pool is 30,000 gallons in a U shape. It is mostly 4 feet deep. I seem to have to add water daily and am losing 1 - 2 inches per day. I had someone come out over the winter And he said it was unlikely that it was a leak. The only thing he didn’t test were the lights. Any ideas or is this normal? Sorry this is our first pool

 

[ajw22]

Welcome to TFP.

Depends on the weather conditions around the pool. Wind causes a lot of evaporation.

Read Evaporation of Pool Water - Further Reading

 

[Cdtipton]

It has been quite windy this year.

 

[NowintersinAZ]

Every thing I have found only gives a snapshot of the day. I am trying to figure out how to see the enter day. What I have done is use this formula (see below) and input it into a spreadsheet as E=(PAW)/(T+459.67) This gives me the same out as the original formula. Then I looked at a weather station near my house on weather underground and found the average (T)emp and (W)ind speed for the previous day. I also would input the average temp into a mmHG calculator and use the for P. My thinking is this give me a closer snapshot of the entire day. I know that wind is suppose to be at the water surface and there are many factors to take into account, like windbreaks. My pool is above ground and there are only windbreaks on hte north. It's rare for the wind to come from the north in the summertime here in Mesa, az.

For those that know math or evaporation better, am I closer or further from the truth?

 

[HeyEng]

Every thing I have found only gives a snapshot of the day. I am trying to figure out how to see the enter day. What I have done is use this formula (see below) and input it into a spreadsheet as E=(PAW)/(T+459.67) This gives me the same out as the original formula. Then I looked at a weather station near my house on weather underground and found the average (T)emp and (W)ind speed for the previous day. I also would input the average temp into a mmHG calculator and use the for P. My thinking is this give me a closer snapshot of the entire day. I know that wind is suppose to be at the water surface and there are many factors to take into account, like windbreaks. My pool is above ground and there are only windbreaks on hte north. It's rare for the wind to come from the north in the summertime here in Mesa, az.

For those that know math or evaporation better, am I closer or further from the truth?
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While I am not a wizz at math, I would say this is an incomplete formula for figuring evaporation rates. What is the actual wind at pool surface? What is the dewpoint? What is the current solar radiation (than can change by the minute)? Just way too many variables that aren't included.