Have you ever seen an intense basketball game where the players sweat a lot? It's like their bodies turn into tiny puddles.
Lakes are sort of like basketball players during a summer heat wave. They sweat, too. But instead of sweat, it is water rising into the air that is lost.
On a hot, sunny day, water at the surface of a lake turns into vapor and literally rises up into the sky. This means less water is left in the lake. This sneaky water-vanishing act is called evaporation.
Wind can also assist in stealing water. It's much like a giant fan has been placed across the water to blow it away. The greater the wind, the greater the rate at which water will evaporate. That's why, on hot, dry, windy days, a lake can really be zapped.
And, if enough rainfall doesn't arrive to compensate, the water levels go down.
Evaporation has an incredible impact on our favorite bodies of water, such as BRA-owned Possum Kingdom Lake, and lakes Granbury and Limestone.
You think lakes have always been and are there, solid as a rock. But instead, they're more like huge sponges soaking up that juice from the sun's rays and then — poof! — slowly disappearing.
The Brazos River Authority keeps track of this watery Houdini act. They even do the math and measurements in an attempt to figure out exactly how much water is disappearing. It's like being a water detective! So, the next time you're hanging out at the lake, just remember this: while it might look all calm and peaceful from your chair, there's really a silent battle going on between the water and the atmosphere.
For many Brazos River Authority employees, monitoring the effects of evaporation is a daily practice. Those effects are highest during the summer months as temperatures soar across the Lone Star State.
Water conservation and smart usage are important year-round, as Texans never know when the next drought will start or when the skyrocketing temperatures of summer will last longer than usual.
There are some ways that you can alleviate the effects of evaporation during everyday chores. When not in use, place a cover over your pool to slow evaporation loss.
When watering your plants during the summer, try watering when the sun is down, as it can greatly reduce the amount of water lost to evaporation. The same goes for watering your lawn. Always water before 10 a.m. to avoid heat evaporating the water before it has a chance to quench your lawn.
Though it can be frustrating for those who live near Texas lakes or turn to them for recreation, fluctuating lake levels are a sign that reservoirs are successfully supplying water to thirsty Texans during times of need and that the water cycle is still turning its wheels.
So, how much does evaporation impact our lakes? See the Brazos River Authority's water accounting summary here.