Importance of Swimming Pool Temperature

Some swimming pools are warmed in chilly months by an electrical gas-powered heater, while others' temperatures are left to the seasonal climate changes. The ideal temperature for swimmers to remain comfortable in a swimming pool is between 78 degrees and 82 degrees Fahrenheit, according to the U.S. Department of Energy.

  1. Temperature

    • The ideal temperature for a swimming pool used for competitive races is 78 degrees, the U.S. Department of Energy reports. Pools generally used for exercise purposes are commonly kept at this same temperature, with those used for lounging or relaxation are kept at a higher temperature. In outdoor swimming pools that don't have a heater, the temperature of the water in colder months and early in the summer may make swimming uncomfortable.

    Evaporation

    • Water temperature has a direct effect on the rate of evaporation within a swimming pool. Higher water temperatures, greater wind speeds and humidity levels will increase the rate of water evaporation. High evaporation levels require an increase in pool maintenance, such as an increase in chemical use to protect a pool from a buildup of solids that can lead to a reduction in chlorine levels and algae growth. As high evaporation rates require higher refill rates, the use of a pool cover can decrease the refill rate by between 30 percent and 50 percent.

    Algae

    • Higher water temperatures allow algae to become more active in reproduction than when water levels are cooler, according to the Swim University. The combination of high water temperatures and the reduction in chemicals, due to high temperatures and increased sunlight, allows increased algae build-up. High water temperature can lead to a build-up of green and mustard algae that can lead to cloudy areas within the pool, which is the result of dead algae remaining in the water after chemicals kill them.

    Energy Use

    • The use of heaters for swimming pools allows a user to control the temperature of the water independent of seasonal climate changes. However, each increased degree of water temperature using a gas or heat-pump water heater will increase the cost of the pool's energy by between 10 percent and 30 percent, according to the U.S. Department of Energy.