Dewey Case of CMAHC to Aquatic Directors: Clear Water Can Still Kill

Picture this: You're standing poolside at a beautiful resort, admiring the crystal-clear water that sparkles invitingly in the sunlight. The saltwater pool looks pristine, and you're ready to dive in with confidence. But what if everything you think you know about pool safety is wrong? What if that clear, seemingly perfect water could actually harbor deadly pathogens?

In a recent episode of the Talking Pools Podcast, Dewey Case, Technical Director for the Council for the Model Aquatic Health Code (CMAHC) and Assistant Aquatic Superintendent for Williamson County Parks and Recreation, sat down with host Natalie Hood to shatter some of the most dangerous myths in the aquatic industry. His message is clear and urgent: assumptions about pool safety can literally be life-threatening.

The Saltwater Pool Deception: It's Still All About Chlorine

Perhaps no myth frustrates aquatic professionals more than the widespread belief that saltwater pools are chlorine-free. This misconception has become so pervasive that it's not just pool owners who believe it—some industry professionals perpetuate this dangerous myth.

You know, this is one of these things that just, whenever I hear it, it just makes my head explode. And, you know, it's pool owners, they're not the experts, right? It's understandable when pool owners believe that, right? What really gets me is when pool pros, so quote-unquote pool pros do this. It's really a marketing thing, right?

— Dewey Case, Talking Pools Podcast

The reality is that saltwater pools are chlorine pools—they just generate their own chlorine through electrolysis. The technical term that professionals should be using is "chlorine generators," not saltwater systems. When salt passes through the generator cell, it produces hypochlorous acid—the same sanitizing agent found in traditional chlorinated pools.

This distinction matters beyond semantics. The chlorine generation myth can lead to serious problems, especially in commercial applications. Case explains that he's witnessed pool companies attempt to install residential-grade salt cells on commercial pools with disastrous results. These undersized systems can't keep up with higher bather loads, leading to constant algae problems, excessive chemical additions, and sometimes complete system replacement within a year.

For HOA pools and other semi-commercial applications, proper sizing becomes even more critical. A neighborhood pool that hosts summer swim leagues requires industrial-grade equipment, not the same system you'd install in a backyard residential pool.

Clear Water Can Kill: The Invisible Dangers Lurking in Perfect Pools

If the saltwater myth makes professionals' heads explode, the "clear water equals safe water" belief should terrify everyone. This dangerous assumption puts swimmers at risk from pathogens that thrive in crystal-clear water.

Clean, clear water does not always mean clean water, does not always mean healthy water. Right. There are various contaminants and pathogens that can exist.

— Dewey Case, Talking Pools Podcast

Case draws a powerful analogy to illustrate this point: Tennessee's mountain streams run crystal clear, but drinking from them will leave you with "screaming diarrhea for two weeks." The same principle applies to pools and aquatic facilities.

The Cryptosporidium Threat: A Two-Week Nightmare in Clear Water

Cryptosporidium, commonly known as "crypto," represents one of the most persistent threats in aquatic facilities. This parasite can survive in properly maintained pool water for extended periods, remaining highly infectious even when the water appears perfectly clear.

The numbers are sobering: crypto can survive at one part per million chlorine and 7.5 pH for two full weeks. During this time, it takes just 10 oocysts or fewer to cause infection—a microscopic amount that's impossible to see. Once infected, victims face two weeks of severe gastrointestinal distress.

What makes crypto particularly dangerous is its resistance to standard chlorine levels. Unlike bacteria and viruses that die quickly in properly chlorinated water, crypto requires either much higher chlorine concentrations or alternative disinfection methods like UV or ozone to be effectively neutralized.

The Brain-Eating Amoeba: When Clear Water Turns Deadly

Perhaps no pathogen strikes more fear than Naegleria fowleri, commonly called the brain-eating amoeba. Case shared chilling statistics about this rare but almost universally fatal organism that can exist in clear, seemingly safe water.

It's like a 99. I forget the exact number. It's 99.4 or something fatality rate. We only have two known survivors... there comes a point to where sometimes death is the greater mercy. These are individuals that they will never get married. They will never have children. They will never have what we would consider a meaningful life because they are horribly, horribly brain damaged.

— Dewey Case, Talking Pools Podcast

With only 164 documented cases over the past 50-60 years but a fatality rate exceeding 99%, Naegleria fowleri represents the ultimate example of why clear water cannot be trusted without proper chemical verification. The amoeba enters through the nose, travels along nerve pathways to the brain, and begins destroying brain tissue.

Tragically, the two known survivors face severe, permanent brain damage that leaves them unable to live independently. Recent cases have been linked to splash pads with crystal-clear water, highlighting that even the most innocent-looking aquatic features can harbor deadly threats.

Beyond the Big Names: Other Clear-Water Contaminants

Crypto and Naegleria fowleri grab headlines, but they're not the only pathogens that can thrive in clear water. Shigella and E. coli can also survive in pools with low or zero sanitizer levels, causing everything from gastrointestinal illness to more severe complications.

These pathogens underscore a fundamental truth: visual inspection is never sufficient to determine water safety. The most dangerous pools are often those that look perfect but lack proper chemical maintenance.

Education: Your Best Defense Against Dangerous Myths

Case emphasizes that ongoing education remains the most critical tool for aquatic professionals. The industry lacks formal degree programs, making self-directed learning essential for anyone serious about water safety.

The sad reality is all too often you're responsible for your own education... we're still the Wild West. You can't go to college for this.

— Dewey Case, Talking Pools Podcast

He recommends starting with qualified operator courses like CPO, AquaTech, or AFO, then advancing to specialized training through distributors, industry conferences, and resources like Google Scholar for peer-reviewed research.

Key educational opportunities include:

• NSPF CPO certification courses
• World Aquatic Health Conference
• International Pool and Spa Expo
• Distributor-sponsored training sessions
• Online resources and peer-reviewed research

The investment in education pays dividends in safety, liability protection, and professional credibility. More importantly, it can prevent the tragic consequences of believing dangerous myths about pool safety.

The Bottom Line: Test, Don't Guess

Case's expertise delivers a sobering reality check for anyone involved in aquatic facility management or pool ownership. The myths surrounding saltwater pools and clear water safety aren't just misconceptions—they're potentially deadly assumptions that put swimmers at risk.

The solution isn't complex, but it requires discipline: regular chemical testing, proper equipment sizing, ongoing education, and a healthy skepticism of anything that seems too good to be true. Whether you're a pool professional, facility manager, or homeowner, remember that clear water can still kill, and saltwater pools are still chlorine pools.

In an industry where marketing often trumps science, professionals like Dewey Case serve as crucial voices of reason. His message is simple but vital: when it comes to water safety, test your assumptions as rigorously as you test your water chemistry. Lives may depend on it.

Episode Chapters

• 00:00 Introduction and Halloween Plans
• 05:30 Saltwater Pool Chlorine Myth
• 12:15 Equipment Sizing for Commercial Applications
• 18:45 Education Recommendations for Pool Professionals
• 25:20 Clear Water Safety Myths
• 30:10 Cryptosporidium Dangers
• 35:45 Brain-Eating Amoeba Risks