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What to Do After Wildfires

By Terry Arko

The Ingredients of Fire-Fighting Suppressants

Most of the dry suppressants dropped on wildfires are a made primarily of di-ammonium phosphate. The result of this is an increase in ortho-phosphate ending up in the waterways and in swimming pools. Phosphate in pools leads to many water quality issues and can combine with calcium to form calcium phosphate scale on heat exchangers. In 2003, the Cedar Fire in San Diego was one of the biggest wildfires in California history. After that fire, pool service professionals reported a very high spike in phosphate levels in pools. This could have been in direct relation to the large amounts of phosphate-based suppressants that were dropped in the area.

In cases where homes were not damaged but were in a vicinity to the fire, the following steps can be taken:

  • Remove all larger debris as soon as is possible.
  • Brush all surfaces thoroughly.
  • Skim smaller material with a pool net.
  • Make sure filter is clean and in operational order.
  • Inspect all equipment.
  • Super-chlorinate the pool to 20 ppm or use a quality chlorine-free oxidizer.
  • Follow immediately with a clarifier to help remove small ash material to the filter.
  • Use of an enzyme can help break down some un-filterable non-living organic material.
  • Test and treat for phosphates once the chlorine levels have come down below 5 ppm.
  • Add a good broad-spectrum algaecide.
  • Clean filter as necessary throughout this process.

Further Cautions

The extreme heat from fires can cause the ground to bake, leading to a lack of absorption. The heat bakes the soil forming a solid layer that causes it to repel water. This is a condition known as hydrophobicity. When rains come, the hydrophobic condition of the soil increases the rate of water runoff. Water can concentrate in these areas, causing erosion. Excessive erosion can come from firefighting efforts and lead to flooding during rains. Pool areas need protection with sandbags or other diversion methods to drains to prevent an influx of floodwater in the pool.

Pools drained during the fire will need to be inspected for damage to plaster surfaces, deck areas and all equipment connections. Most likely, these pools will need to be re-surfaced before regular use can begin.

In conclusion:

  • Use extreme caution in areas where wildfires are active.
  • Always check ahead of time with emergency management personnel before attempting to enter neighborhoods where fires have been.
  • Wear smoke protection when necessary (breathing mask and goggles).
  • Water in pools can contain toxins from smoke and ash and firefighting chemicals it is best to drain when possible. No one should ever swim in a pool in the immediate aftermath of a fire.
  • Remember that wildfires can move fast and change course in seconds. Have more than one escape route planned ahead of time. It is best to stay out of the area.
  • Shock, floc, enzyme, phosphate removal and algae prevention are all good remedial treatments once the fires are gone.
  • Check and inspect all equipment thoroughly during the cleanup process. Filters may need to be backwashed and cleaned frequently during this time.
  • Ensure that pools equipped with firehose pumps also have hydrostatic relief valves to prevent popping from rapid draining.
  • Be aware of erosion and flooding problems that may occur from damaged soil. Sand bag any vulnerable areas in advance. Ensure that the flow of water is to drains and culverts to prevent flooding.

Terry Arko has more than 30 years of experience in the pool and spa/hot tub industry, working in service, repair, retail sales, chemical manufacturing, customer service, sales and product development. A Certified Pool Operator (CPO) and CPO Instructor through the National Swimming Pool Foundation (NSPF), Arko is currently a water specialist for NC Brands, parent company of SeaKlear and Natural Chemistry, which is a manufacturer of pool and spa products. For more information, visit www.ncbrands.com.