I remember when I had my swimming pool newly installed, I was really excited about being a new pool owner. This also meant I knew very little about my swimming pool or any other type of swimming pool.
The installation was complete and it was time to fill the pool up with water. All I knew was that I would have to contact a trucking company to supply the water for the pool. I got on the phone all excited to get the company to supply the water.
My excitement however faded very quickly when the responder from the trucking company on the other end of the phone asked “so how many gallons of water do you need?” This was the moment I realized that I didn’t even know the quantity of water my pool would need.
I told the person on the phone I was going to have to call back, ended the call, and went to do some research. This experience made me realize that many new pool owners are actually like me and so, I have decided to share the results of my research with you.
Call it doing my part to help you avoid extra stress and keep the excitement about owning your new pool or filing your pool back up. Since my pool is a 24foot round pool, let’s begin with that.
A 52inchdeep 24foot round pool holds approximately 11,420 gallons of water.
Table of Contents
How Do I Calculate How Much Water Is In My Swimming Pool?
Calculating the quantity of water a swimming pool can hold is achieved by calculating the volume of the swimming pool. This method basically treats the swimming pool like a gigantic container and it makes use of mathematical methods and formulas. There are certain things to note while calculating the volume of your swimming pool, they are discussed below
The first thing to take note of in the steps to calculate the volume of a swimming pool is the identification of the shape of your swimming pool. The shape of your swimming pool refers to the form in which your swimming pool is constructed or manufactured.
The reason for this is that different shapes have peculiar formulas with which their volume is calculated. These formulas also would require certain measurements and dimensions as variables. These required variables can vary from formula to formula and from shape to shape by extension.
The second thing to note about calculating the volume of your swimming pool is that certain variables will be required to arrive at an answer. These variables are the pool dimensions and measurements.
Taking these measurements is straightforward and can be done with the help of a simple measuring tape without any need for prior experience or training. The required measurements include the length, breadth, diameter, and radius in the case of a circular pool and average depth (calculated by using measurements of the deepest and most shallow depth).
The third thing to pay attention to is that many times, the amount of water the swimming pool can hold is calculated to an estimated figure. This means that the number of gallons to fill up your pool may fall below or above the results of your calculations. One thing’s sure though, the figure is going to be extremely close.
For a Round pool
The formula to calculate the volume in gallons of a round pool is 3.14 ×r2× D × 7.5 = V (in gallons)
Where;
r2 is the square of the radius of the swimming pool in feet
D is the depth or average depth of the swimming pool in feet
3.14 is the value of Pi
7.5 is a constant
And V represents the volume or capacity of the swimming pool in gallons.
Below is a chart showing the volume of the most common round pool sizes;
POOL SIZE (ROUND)

48INCH WALL  52INCH WALL 
12 ft  2,975 gallons  3,389 gallons 
15 ft  4,646 gallons  5,310 gallons 
18 ft  7,646 gallons  8,602 gallons 
21 ft  9,106 gallons  10,408 gallons 
27 ft  15,054 gallons  17,205 gallons 
30 ft  18,585 gallons  21,240 gallons 
33 ft  22,488 gallons  25,700 gallons 
12 by 24ft (oval)  5,948 gallons  6,797 gallons 
15 by 30ft (oval)  9,293 gallons  10,620 gallons 
16 by 32ft (oval)  10,573 gallons  12,084 gallons 
18 by 33ft (oval)  12,267 gallons  14,0194 gallons 
For a rectangular pool
The formula to calculate the volume of a rectangular pool with one depth (no shallow or deep end) is L × W × D × 7.5 = V (in gallons).
Where;
L is the length of the swimming pool in feet
W is the width of the swimming pool in feet
D is the depth or average depth of the swimming pool
7.5 is a constant
And V represents the volume or capacity of the swimming pool in gallons.
Below is a chart showing the volume of the most popular rectangularshaped pool sizes;
POOL SIZE  4 FT AVG DEPTH  5 FT AVG DEPTH  6 FT AVG DEPTH 
14 by 28  44,400 gallons  55,500 gallons  66,600 gallons 
16 by 32  58,000 gallons  72,500 gallons  87,000 gallons 
18 by 36  73,400 gallons  91,750 gallons  110,1000 gallons 
20 by 40  90,600 gallons  113, 250 gallons  135,900 gallons 
25 by 50  141,600 gallons  177,000 gallons  212,400 gallons 
For a freeform shaped pool
Calculating the volume for a freeformed shape pool can be a little tricky. This is because the shape of the pool is not regular and so there is not one known formula or calculation that helps you arrive at the exact volume of the swimming pool.
What seasoned experts advise is to break down the swimming pool into different segments of regular shapes and then calculate the volume of those regular shapes individually. The total volume of the entire swimming is now gotten by adding up the volumes of the individual regular shapes.
When Do I Talk To A Professional?
Knowing the volume of your swimming pool goes beyond just knowing the number of gallons of water in your pool, it forms the basis of all chemical processes and additions that are required to keep the swimming pool in a pristine condition.
You may need to hire a professional if you find it challenging to calculate the volume of your swimming pool. This could be a result of not being able to accurately measure the pool dimensions or not knowing the correct formula to apply.
I have especially found that freeform pool owners face the most difficulty in taking a shot at calculating the volume of their swimming pools. You should therefore strongly consider hiring a professional to calculate the volume of your swimming pool if you do not trust your measuring and calculation skills or you own a complex freeform shaped swimming pool.
How Much Does It Cost To Fill A 24 Feet Round Pool?
The first step in estimating the cost of filling any swimming pool is to know what the volume or capacity of that pool is. This can be done by using accurate pool measurements or dimensions and applying the appropriate formulae.
After you have calculated the capacity or volume of water your pool can hold, contact your local trucking company to ask for the price per gallon or 1,000 gallons of water that they supply. The price varies throughout the country but you should expect to pay somewhere between $4 and $10 depending on your location in the country per 1,000 gallons.
Going by these figures, the estimated cost of filling up a 24foot round swimming pool is between $46 and $115 depending on where you are in the country.
How Long Does It Take To Fill A Swimming Pool?
Filling the swimming pool is the final chapter in installing a swimming pool. The process is the last of all of the work you need to have done before you can finally dive in and start enjoying the satisfaction swimming has to offer.
Many times, I have found that this waiting period feels like an eternity. So, let’s talk about how long it takes for the process to be complete? Going by statistics, it takes anywhere between 12 and 24 hours to fill up an average pool.
The specific time will be dependent on a number of factors which include the size of your swimming pool, the pressure of the water coming in, and the number of input sources you are using.
For example, it would take more time to fill up a pool if you were just running through one hose than when the water comes in from multiple sources. Also, if the supply of water is at the same rate, a 20 feet pool will get filled up before a 24 feet pool.
It takes approximately 9 hours to fill in 5,000 gallons of water using a standard half (½) garden hose, since the 24 feet round pool can hold 11,420 gallons, the estimated time to fill up this pool can be put at 20 hours.
Alternatively, a water trucking service can inform you of the pressure and the exact number of gallons pumped in by the hour. Then you use these figures to calculate the number of hours that will be needed for your swimming pool to be filled up with regard to the volume of your swimming pool/ the number of gallons of water it can hold.