How does Rainwater Affect Pool Water?

As you know, Virginia has been experiencing record breaking rainfall since December 2023.  As such, let’s discuss the effects of rain on your pool water.   

Rain which is formed from evaporated water, leaves behind minerals, carbonates and dissolved solids on earth, as it evaporates into the air. And just before it condenses into rain droplets it is the purest water on the planet. As rain falls through the air, it picks up small amounts of pollutants, spores, dust and other contaminants. 

Heavy rains carry organic farm / ground pollutants such as phosphates into your water source.  Algae loves phosphates.

In addition, rainfall dilutes pool chemistry levels and lowers the readings for pH, alkalinity, hardness, stabilizer, and chlorine.  As such, we expect many of our client’s pool chemistry to be in poor condition at the start of the 2024 season. 

Do Heavy Rains Cause Pool Algae?

Rainwater itself does not cause algae, but it can provide the right environment for algae. Rain will bring phosphates, nitrates and other organic contaminants into the pool.   Rain also reduces chlorine and/or salt levels in your pool.   

Whenever large amounts of rain are forecasted in our area, make sure you are running your pool pump and filter around the clock for twenty-four hours while the rain is present and after it ends. 

For Spring Pool Opening season, JDO will be using several opening chemicals to bring the pool water back into balance.

It is important to maintain your pool water chemistry on a weekly routine. If we have daily rainfall, you need to be checking your chemicals after the rain.                                 

As always, routine maintenance on your own or by using a pool professional is your best prevention plan for problems with your water chemistry.