After a monsoon storm, get the debris out, make sure the pump is running again, and bring the chlorine back up within a day. Dust and leaves use up chlorine fast, and in late-summer heat a pool that's left alone after a storm can start turning green within a couple of days.
Monsoon season in Arizona runs from June 15 through September 30, and the East Valley usually sees its biggest storms from July into early September. Queen Creek and San Tan Valley sit close to open desert, so dust storms there can be heavy. Here's how to deal with what they leave behind.
What a storm does to your pool
A single storm can hit a pool in several ways at once.
- Dust and dirt. A haboob can drop a layer of fine dust across the water and the floor. It clouds the water and clogs the filter.
- Leaves and debris. Wind brings in palo verde twigs, mesquite pods, desert grass and whatever was in the neighbor's yard.
- Chlorine loss. Organic matter, dust and rainwater all use up or dilute chlorine. Readings are often near zero the morning after a big storm.
- pH swings. Heavy rain and debris can shift the water's pH and alkalinity, which makes chlorine less effective.
- Power outages. If the power went out, the pump and timer may not restart on their own, and a salt system stops making chlorine while the pump is off.
- Rising water level. A heavy downpour can push the water above the skimmer opening, which stops the skimmer from pulling debris off the surface.
What to do in the first 24 hours
Work through these in order once the storm has passed and there's no lightning in the area.
- Check that the pump is running. If it's off, check the breaker, then the timer or automation clock. After an outage, timers often need their time reset, or they'll run at the wrong hours.
- Empty the baskets. Clear the skimmer baskets and the pump basket. A packed basket restricts flow and can damage the pump.
- Skim the surface. Get the floating leaves and debris out before they sink and start breaking down.
- Lower the water if it's too high. If the level is above the middle of the skimmer opening, drain it back down so the skimmer works again.
- Brush, then vacuum. Brush the walls and steps to push dust into the water, let it settle, then vacuum the floor. Heavy dust may need to be vacuumed to waste, depending on your filter.
- Test and balance the water. Check free chlorine and pH. Bring chlorine back up, and adjust pH so the chlorine can work.
- Run the pump longer. For a day or two, run the pump extra hours to filter out the fine dust.
- Check the filter pressure. If the pressure gauge reads well above its normal clean level, the filter needs to be cleaned or backwashed.
Electrical safety
Don't touch pool equipment while it's wet from a storm, and don't reset breakers while standing in water. If a breaker keeps tripping, or the pump hums but doesn't start after an outage, leave it off and have it checked. Those can point to a failing motor or capacitor, or water in an electrical connection.
Is rainwater bad for the pool?
Rain itself isn't the problem. Monsoon rain is soft, so it actually dilutes the minerals in the East Valley's hard water a little. The trouble is what comes with it: dust, pollen, debris and runoff from the deck and landscaping. A heavy storm can also wash fertilizer or mulch from planters into the water, which feeds algae. That's why chlorine and pH both need checking after a storm, even if the water looks fine.
Signs it needs more than a cleanup
Most storms only need the steps above. Call for help if you notice:
- The water is still cloudy or turning green two days after you've rebalanced it
- The pump won't start, keeps tripping the breaker, or makes a grinding or humming noise
- The filter pressure stays high even after cleaning
- The pool keeps losing water after the storm, which can mean a leak
- Mud or debris is pouring in from a damaged fence, wall or drainage problem
How to get ready before the next storm
A little preparation makes the cleanup much easier.
- Keep the water balanced and chlorine at the higher end of normal during monsoon season.
- Trim branches that hang over the pool.
- Put away loose patio furniture, umbrellas and toys.
- Leave the pump running during a storm unless there's flooding near the equipment or lightning risk.
- Clean the filter before the season starts, so it has room to catch dust.
When to call a pro
If your pool in Queen Creek, San Tan Valley, Gilbert or Florence is still cloudy or green a couple of days after a storm, a local pro can clear it and check the equipment while they're there. Send a request below or call (480) 788-5344.