October 2016: Natural Disasters
Floods, Hurricanes, and Tornadoes, Oh My!
Weather catastrophes don’t have to destroy your pool
We hope that customers in the path of Hurricane Harvey and Irma have successfully shut down their facilities. Our thoughts are with you, and this month’s Prevention Advisor is designed to help you weather the disaster after it passes.
Swimming pools and spas often are substantially contaminated due to catastrophic events like flooding, prolonged closure, and storm runoff. As a result, there is not one procedure that makes sense for every facility under every set of circumstances. This Prevention Advisor provides guidance on important areas to address when a pool or spa needs to be cleaned and prepared for use after a catastrophic event.
After a catastrophic event, a pool must be evaluated and rehabilitated before use. First, you must isolate the area by placing appropriate barriers to prevent accidental drowning. Next, the facility must be inspected to better understand any prevalent issues and to create a rehabilitation strategy. Untreated water can become a breeding ground for disease-carrying mosquitoes, so treatment and circulation of the water should be priorities. Stagnant water can also breed algae and bacteria which can further contaminate the plumbing and filtration systems once turned back on.
Ideally, all debris, dirt, slime, etc., should be removed from the pool. Next, the system should be decontaminated and disinfected and water should be replaced with potable water. This means you may need to drain and refill the pool, but then normal water treatment operations can commence. Finally, operators should review a start-up and inspection checklist to make sure the facility is ready to use.
- Pool or Spa Assessment/Inspection
- Draining the Water
- Water Replacement and Treatment
Before we dive deep into each step, it is worth noting that other steps may be needed depending on the facility and present equipment. Consult with your equipment manufacturers for the best guidance on specific items. You should also verify with the local health department if an opening inspection is needed. As always, review local health codes to better ensure compliance of the facility.
1.) Pool or Spa Assessment/Inspection
The following represents assessment/inspection items that should be addressed to ensure proper operations before the pool or spa is opened for use.
a.) Inspect the grounds, barriers, gates, safety equipment, the pool itself, deck, bathhouses, and pumps for broken or malfunctioning equipment.
b.) Have a qualified professional inspect and repair or replace equipment or wiring that may be damaged including pumps, controllers, meters, power supplies, grounding, bonding, etc.
c.) Have a qualified technician or contractor inspect and repair or replace heater(s), filter(s), chemical feeder(s), and other circulation system equipment.
d.) Make sure that the main drain is visibly attached, fully intact, and satisfies the requirements of ANSI/APSP-16 drain cover anti-entrapment standard.
In the event the pool does not have dual drains with anti-entrapment covers, ensure compliance with the Virginia Graeme Baker Pool & Spa Safety Act with additional layers of entrapment protection. Replace and/or repair as needed utilizing qualified workers or contractors. For more information about the Act, nspf.org. If main drains are not visible, address this item during a later step.
e.) Inspect all inlets and outlet fittings.
f.) Empty and clean the skimmer baskets or gutters.
g.) Remove debris, sweep, rinse, and disinfect the decks.
h.) Clean the hair and lint strainer.
i.) Restock the first aid kit.
j.) Inspect and replace (if needed) personal protective equipment.
k.) Inspect and replace (if needed) drowning prevention/rescue equipment, warning signs, and other safety equipment.
l.) Make sure the emergency phone is working.
2.) Draining the Water
a.) Depending on how dirty the water is, operators will have to judge if it makes sense to add disinfectant or flocculant/clarifier to begin disinfecting the water and removing solids from the water, plumbing lines, filter(s), and other circulation system components. The second option is to drain and clean the pool and equipment.
b.) Since the groundwater table will be higher than normal after a flood or storm, it is very important that the pool or spa not be drained without a hydrostatic relief valve, to avoid the pool from being “lifted” from the foundation due to groundwater pressure. As a result, a complete drain may not be possible and a partial drain may be the only option.
c.) You may have to wait until the waste water systems in your area are functioning and the water treatment facilities can handle the large volume of water that would result from draining a pool. Before you begin draining, contact the local water department to ensure the system can handle the volume you will be discharging. Follow any normal reporting requirements by the wastewater treatment facility.
d.) If it is safe to drain the pool, use the normal procedure, but take into account the high water table and the possibility of not being able to completely drain the water.
e.) A portable pump may be needed to remove all the water from any place where the water stands and does not drain.
f.) While the water is draining, rinse and clean the sides of the pool several times.
g.) Because the pool is empty at this point, this may be an appropriate time for other preventative maintenance, including an acid wash of the surfaces, installing dual-main drains, painting, and verifying all drain covers comply with ANSI/APSP-16 standards.
h.) In the event the facility decides to clean and treat the pool without draining it, then skip to the decontamination section below.
If the Water Could Not Be Drained
a.) Superchlorinate the water and add water clarifiers or flocculants to help settle debris to the bottom. Test and adjust the water pH until it is between 7.2 and 7.8.
b.) Debris that settles to the pool bottom should be vacuumed to waste to reduce the risk of plugging the filter and to remove contaminants that will consume chlorine.
c.) Maintain the chlorine level and circulate the water. In a spa, make sure that the jets are set at their maximum level, but remember to turn the aerator (blower) on and off about every five minutes while the water is circulating to ensure that the airlines are being disinfected.
d.) Test the chlorine level and pH in the evening and again in the morning to see if the water has maintained a residual. This will help you understand if there is a substantial contamination remaining in the water requiring additional chlorine, flocculants, and/or clarifiers.
If the Water Has Been Drained or Partially Drained
a.) Remove all large debris left behind by brushing the pool shell. You should also check the pool or spa shell for any damage that may have been caused. Test and adjust the water pH until it sits between 7.2 and 7.8.
b.) Once the debris has been removed, clean the pool or spa with a surface cleaner. This surface cleaner can be mild hydrochloric acid solution (10%) or another surface cleaner designed for recreational water applications.
c.) Once the cleaning is accomplished, rinse the surface to remove any cleaner or acid solution.
4.) Water Replacement and Treatment
a.) Refill the pool or spa with fresh potable water
b.) Once the appropriate water level has been reached, turn the circulation system on and begin to balance the water. Ideal water balance levels:
i. 200-400 ppm of calcium Hardness (150-250 ppm for spas)
ii. 80-120 ppm of total alkalinity
iii. pH between 7.4-7.6
For more information about water balance and pool operations refer to NSPF®’s Pool & Spa OperatorTM Handbook.
c.) The disinfectant level should be raised to the level of the local or state health department regulations and product label directions.
d.) To verify that decontamination has been achieved, the pool or spa water should be treated with 10 ppm of chlorine disinfectant.
e.) Allow the pool or spa to circulate overnight, or for a period of 8-12 hours, and then check the disinfectant level in the pool or spa.
f.) If free chlorine is consumed overnight, then a demand still exists. If this is the case, inspect and decontaminate plumbing lines, filter(s), and other circulation system components.
g.) If sufficient chlorine residual is found, then proceed with the next step of conducting a complete inspection of all areas of the pool or spa.
We hope you are successful in reopening your facilities after Hurricane Harvey and Irma leaves the area. If you have further questions about disaster mitigation, reach out to us at firstname.lastname@example.org.