November in Australia and everybody must prepare for bush-fire season. But with this relentless drought the danger is magnified and the consequences dramatically increased. This season has started early and threatens to be even more severe than recent years, as there is unfortunately no sign of the drought breaking and also even more unfortunately no plan from those in Canberra to do anything about it.

How to Clean and Repair Swimming Pools and Spas After the Wildfires

Expert Terry Arko provides valuable information about damage caused by fires and how pool professionals can address it.

By Terry Arko

No words can adequately express the condolences felt for those who have suffered loss during the recent wildfires.

But we can do our best to help clients through these ordeals, while protecting our own safety as well. Fires bring unique problems, which I will address here.

After the fire

All types of debris are deposited in pools, spas and backyards during times of wildfires as result of high winds. Smoke, ash, tree branches, leaves and fire suppressant chemicals will all most likely end up in the pool.

Smoke and ash can be a problem for miles beyond the fire. It has spread all over the east coast of Australia, depending on the direction of the wind, and is visible on radar. The airborne ash and debris is affecting many pools in this area. Some of the pools developed filter problems and bouts of algae.

Clean-up after a wildfire can take time and should be pursued with care.

Always check ahead of time with emergency management personnel before attempting to enter neighbourhoods directly hit by fires.

Pay special attention to your surroundings at all times. Be aware of live downed power lines. In many cases in fire-damaged homes, the fire department will turn off the power. This is done because wires may have melted or been fused from the heat. Be sure to check with the fire department before attempting to turn pump and filter breakers back on. Only a licensed electrical contractor should determine the integrity of the breakers for the pumps.

The contents of ash

In the case of wildfires, there will be a lot of ash that ends up in pools. Ash from fires that burn lower than 840 degrees Fahrenheit is mostly organic carbon. At a higher temperature, the carbon is burned away and inorganic compounds are left. These include things like calcium, magnesium and sodium.

The fires in NSW and QLD not only burned forest, but also homes and structures. Because the combustion rate is much higher for buildings, the make-up of the ash is much more different. At a very high combustion rate, the ash can contain potassium and calcium oxides which create quicklime. If enough of this ash gets into the pool and then to the filter, it can create a limestone cement coating on the filter media. Ash from homes and structures can also contain toxins such as lead, arsenic and hexavalent chromium. Most of the ash that lands in pool water is also hydrophobic and repels water.

This explains why the ash floats and is so difficult to remove by skimming. Changing the charge of the ash by using a chitosan clarifier or an enzyme can help in the removal of the ash.

Pool Clean Up in Fire Zones

Swimming pools in fire areas will contain ash, debris, firefighting chemicals and toxins. It is best when allowable to drain and re-fill the pool.

The components of smoke from fire can cause severe lasting damage to equipment and structures. Inspect the integrity of the pool walls, plaster, the pipe fittings, decking and surrounding landscape.

In addition, the chemistry of the pool will be adversely effected. Smoke is corrosive and oxidative. It will cause severe damage wherever it has settled. If equipment and decking are covered in ash and smoke, continue to use caution. Wear personal protective equipment and a breathing apparatus as well as gloves. There are many toxins in smoke and ash residue that can cause sickness. The best case is to allow professionals to deal with excessive clean up situations.

Outside immediate fire zones

In cases where homes were not damaged but were in a vicinity to the fire, the following steps can be taken especially for Spa care.

Your cover is critical to help minimise the adverse effects of ash and smoke. A good quality, secure fitting cover with no damage maximises your chances of keeping foreign objects out. But remember that it is not a vacuum seal and cannot be expected to keep it all out, and of course as soon as you take your cover off the air has immediate contact with the water, and miniscule particles of organic matter mix with the water.

This is unavoidable and answers the question of why it happens even though you have hardly used your Spa for warm water massage.

We need to be particularly focussed on the filters and the sanitisers during periods of smoke in the air. Filters will get dirtier much more quickly and even effect the water flow, so they may need to be cleaned more regularly than normal. Warnings like not enough water flowing to the heater are common. It means that cleaning must take place more often, or, though I never recommend buying a second filter and rotating them (allowing time for the filter to soak in an alkaline solution), if you have a second filter this makes the cleaning process much less intensive for you and the end result probably more satisfying as well.

Secondly the sanitiser is working overtime with all the additional organic compounds introduced to the water without our help or even knowledge. Unfortunately, there is no warning that your sanitiser is running low or even run out. Checking the level of your sanitiser is most important during this process as it can very quickly be depleted through oxidising the ash

The following steps can be taken especially for pool care. A regimen of shock, floc, enzyme, phosphate removal and algae prevention makes for a good remedial treatment:

  • Remove all larger debris in the pool and/or spa as soon as possible.
  • Brush all surfaces thoroughly.
  • Skim smaller material with a pool net.
  • Make sure filters are clean and in operational order.
  • Inspect all equipment.
  • Shock your Spa or Super-chlorinate the pool to 20 parts per million (ppm) or use a quality chlorine-free oxidizer.
  • Follow immediately with a clarifier to help send small ash material to the filter.
  • Consider using an enzyme to help break down some of the non-living, organic material that can’t be filtered.
  • Most firefighting suppressants such as those dropped from the air contain phosphate. Be sure to test and treat for phosphates once the chlorine levels dip below 5 ppm.
  • Follow with a good broad spectrum algaecide.
  • Clean filters as necessary throughout this process. They may need to be backwashed and cleaned frequently during this time.

The Aussie Spa Guy