Wildfires and Swimming Pools

Once again, wildfires rage with devastating fury. To say they are a disruption would be an understatement. We sincerely hope your homes and communities are safe. But even if you are not in eyesight of the flames or smoke, there is a good chance swimming pools will be affected in the region. A good rule of thumb is if you can smell it, it is impacting your swimming pool. Debris can travel many miles, and smoke can travel hundreds of miles. Even if a home is not touched by the flames, there is likely to be a recovery and clean-up process once the flames are finally snuffed out.


We at Orenda have been receiving an abnormally large amount of calls, emails and facebook messages asking questions about how to recover their pools after the wildfires. So to better understand this, let’s start with the facts.

Ash and debris need to be cleaned out

Ash, soot and other debris that is created from the wildfires can go airborne and travel in the wind. If it gets in your pool, this debris either needs to be filtered or vacuumed out of the pool. There are no shortcuts to this, as physically cleaning the pool will be the best way to get large particles out of the water. Furthermore, fire debris can contain organic carbon, phosphorus, and nitrogen.  These can potentially create a phosphate and a nitrate problem for your pools. The ash will also tend to be more alkaline, which can cause the pH of the water to increase. This debris is great for gardening, but not for our pools.

Related: Phosphate Removal (Pillar 3)

Filtering and vacuuming the pool will dramatically improve any chemical treatment you follow it up with. Again, we strongly advise against any shortcuts to actually cleaning the pool. We also suggest cleaning the deck around the pool, perhaps with a garden hose to clear debris off the deck that may otherwise find its way into the pool after you leave.

Flame retardants can contain phosphates and sulfates

According to some sources we found online, the flame retardants that are commonly used to fight wildfires can be comprised of up to 10% fertilizer (like ammonia phosphate and sulfate ions). The mixture is dropped on the fires from planes and helicopters and creates a sticky solution that is designed to help “smother” the flame until it can be better controlled. These retardants can also travel in the wind and could potentially get in your pool…but probably only if you’re relatively close to the blaze.
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Fire retardants dropped from helicopters are loaded with phosphates. If your pool looks like this, draining and refilling is probably the best option. Image Credit: AP - Kent Porter

Perhaps you’re fortunate enough to not be in the line of fire, and you’re far enough to be safe from the wildfires. You’re probably already aware that having a pool in the backyard means your water is fair game for firefighting helicopters. Consider that the vessels these helicopters tow are constantly flying over the worst of the wildfires. Ash, smoke, and whatever else is rising from the flames can be on the vessel that dips in your pool to capture water. Sure, there are enough pools in Southern California that yours is not likely to be drawn from. But if not, there’s a good chance that helicopter’s water vessel shared some ash and debris with your water.

Related Article: Smoke on the Water and Ash in the Pool - Robert W. Lowry, PCTI

Smoke and ash travel

Unlike the flame retardant, the smoke and airborne particles can travel a long way from where the fire is being contained. It is not uncommon for this smoke to travel hundreds of miles—and depending on how high it rises, it can be thousands of miles. So, if you’re in the general vicinity of a wildfire it would be safe to assume your pool is being affected in some way. Just because you’re not in the direct line of danger does not mean your pool is not being affected. In the case of an otherwise clean looking pool, we suggest testing water for phosphates and nitrates anyway. These things may go unseen but can impact your pool chemistry. We suggest you err to the side of caution and test your water for these micronutrients.

Wildfires will continue

As wildfires seem to be a more common occurrence and the winds are blowing, this reality is something that has to be managed. You can expect these wildfires to happen year after year. All the ash and debris that settles in our pools create a perfect environment for chemical inefficiencies and stress on equipment. As you know from reading the Orenda Blog, phosphates and nitrates can create massive chlorine demand and inefficiencies. Wildfires can drop an all-you-can-eat buffet of micronutrients in a pool, so be prepared.

All that being said, along with proper circulation and filtration, some Orenda products can aid in the cleanup process. Our CV-600 Enzyme Water Cleaner will help speed up the cleanup process by managing the non-living organics falling into the pool. Our PR-10,000 Phosphate Remover Concentrate can handle the baggage of the excess phosphorus finding its way to the water. If you still have particles that you need help cleaning up, you can try CE-Clarifier too. But nothing will replace physically cleaning the pool and filters.

Good luck out there, and if the blaze is headed your way, don’t wait…be safe and evacuate.

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