Keep It Clean!
Simple Solutions to Pool Water Quality
By Mick & Sue Nelson, USA Swimming Facilities Department
Stop taking a bath in the pool I swim in! What happened to our clear, clean, safe pools? Not sure when we lost control, but we have. We have offered problem solving advice on over 800 pool water quality issues the past 15 years. The main problems are with indoor pools, and they can be serious. There are lots of ways to “mess up” pool water and people are finding more each year.
Some basic information. Indoor air quality is almost totally dependent on pool water quality. We tell our clients that if they have an air-quality problem, cover the pool and it will probably go away. So, focus on the water not the air. All solutions start with water quality. Presuming all pool and HVAC (heating, ventilation, air conditioning) equipment are sized and designed properly and operating efficiently, the first thing to look for are chloramines. Chloramines are formed when chlorine is affected by something in the pool water that shouldn’t be there. Chloramines are what cause the “chlorine” smell in pools.
Chloramine formation can be accelerated by:
- Pool users not properly showering before entering pool. A 30-second warm-water shower/rinse to remove Personal Care Products * can solve 80% of the problems.
- People using the pool rather than getting out and going to the restroom.
- People doing a high level of aerobic activity and sweating in the water. (Everyone sweats in the water – the same as if they were doing exercise on land)
- Residues from ammonia-based cleaning products that are used on decks or in shower rooms/lavatories.
- Residues from fertilizers used on landscaping (nitrogen-based) that get tracked into building on shoes.
- Poor air circulation and lack of fresh air introduction into the pool building.
- Overuse of “shocking” the pool for maintenance purposes – you only shock when a specific bacterial problem has been identified. Shocking the pool can create a whole new set of problems and has been found NOT TO BE EFFECTIVE as a solution for chloramines.
- Improper use of certain brands of chemicals not suitable for conditions specific to a geographic area.
- City water containing chloramines.
There are standard water tests for chloramines. Most state codes require these tests be taken and recorded 2 or 3 times daily. Usually more than one thing needs to be changed to alleviate the problem. The most common methods are:
- Change the air circulation system to include more fresh air introduction and better turnover or more efficient closed-system circulation and dehumidification.
- Evaluate the type and brands of chemicals being used to treat the pool water for both chlorine and pH control.
- Evaluate the pool filtration system to see if a filter that filters down to a more effective micron rating (like DE at 4 microns) would help.
- Check the labels on all cleaning products to make sure they do not contain ammonia or are not nitrogen enriched.
- Have pool staff attempt to get the users of the pool to take showers before entering – this is usually required by state health codes. THIS IS SUPER IMPORTANT. Remember, a 30-second warm shower rinse can help alleviate 80% of the problem.
- Consider installing a medium pressure ultraviolet (UV) water treatment system that cuts down on the amount of chlorine you must use and “breaks down” mono, di and tri chloramines.
- If the city is using chloramination rather than chlorination, install an activated carbon filter on the pool freshwater fill line. This will remove chloramines from the source water before it gets into the pool.
Pharmaceuticals* enter pool water via urine, sweat, body surfaces and swimwear. The main chemicals found in the water – that shouldn’t be there are:
• Ibuprofen & Acetaminophen
• Anti-Epileptic meds
• TECP (a flame retardant used in the manufacturer of swimsuits
• DEET an insect repellant.
Estimates are that 14ml per-hour are ingested by swimmers (including children). These chemicals are not filtered out by pool equipment. They can have a half-life in the pool as-long-as 2 to 3 days.
*PPCPs = Pharmaceuticals and Personal Care Products. Basically, our source water (drinking water) and pool water are being contaminated by people. Residues from personal care products such as shampoos and conditioners, deodorants, hair products, perfumes, lotions, etc., are ruining our pool water. Studies show only 12% of pool users shower before getting in. 1 in 5 people admit to having urinated in pool water. One person peeing in pool can affect 10,000 gallons of pool water for 9 days.
Pool users are causing the problems. Changing their habits can be a major part of the solution. Look for the related Student Handout – What’s In Your Pool? – that you can personalize and distribute to your pool patrons to increase awareness and education.
Mick Nelson, BS Business administration, MS in Education, is the Senior Facilities Development Director for USA Swimming. He comes from a club coaching background along with extensive experience in business and aquatic management. Mick’s specialty is business development, programming, water treatment and aquatic facility design.
Sue Nelson, BS Exercise Science, is the Aquatic Programming Specialist for USA Swimming. Her specialty areas are program development, implementation and facility design. Sue was the recipient of the AEA 2012 Lifetime Achievement Award, 2019 NDPA Lifetime Achievement Award and the ATRI Tsunami Spirit Award.