How to Cool Your Pool Water

Although this summer appears that it will be much milder than the last two summers, it is still very hot this time of year.  Traditionally one of the solutions to dealing with the summer heat is the cool enjoyment that a swimming pool can provide.  That is not always possible in August—as pool water tends to heat up, oftentimes past the point of being refreshing.

Most swimmers like water in the range of 80-90 degrees, with temperatures below 80 and above 90 being considered uncomfortable.  With the water temperature in many full-sun pools now reaching the low-90’s, pool owners are looking for ways to lower the temperature of the water.

Following are some methods that have been used to lower the temperature of their pool water:

Fountains & waterfalls—Fountains and waterfalls lower the water temperature—as the water action that is created by fountains and waterfalls causes evaporation, which cools the water.  This also tends to cause more water loss due to this evaporation.   Operating the fountain or waterfall at night is most effective as the air temperature is cooler.  If your pool is not equipped with a fountain or waterfall, aftermarket fountains are available that attach to the pool return.

Ice—Ice can also cool a pool, but it is really not a practical method of cooling pool water—as it takes an excessive amount of ice and the change is only temporary.  According to an article in the Wall Street Journal, it would take 8,750 pounds of ice to lower the water temperature of a 20,000 gallon pool by 10 degrees.  These numbers are fairly consistent with research done by Mythbusters—so you can see that ice is not a sensible method of cooling the water.

Drain & refill—A partial drain and refill of your pool water is another option, depending on your water source.  This method definitely works, especially if your water source is from a well, as well water is typically much cooler this time of year than surface water.  Denton and most other large municipalities in the north Texas area depend on surface water (lake water) as opposed to well water, but most water sources for pools outside of these municipalities are well water, making this option something to consider.  One factor to consider before implementing this strategy is that you will have to rebalance your water chemistry, and also the fact that it is wasteful.

Shade the pool—Although it will not help you this summer, consider planting some trees around the pool, especially on the west side.  But remember, if you choose deciduous trees, you will be cleaning leaves out of the pool in the fall.

Reversible heat pumps—Reversible heat pumps will either heat or cool pool water with the flip of a switch.  Although they are fairly expensive and consume a considerable amount of power to operate, they are effective when it comes to cooling pool water.

Evaporative coolers—Evaporative coolers use evaporation to lower the temperature of your pool water.  They are considerably less costly to purchase and operate than a heat pump, but they are not capable of being used as a heater in the winter as a heat pump is.

As you can see, there are quite a few options available for lowering the temperature of your pool water, some more practical than others.