Splashpads & Illnesses

Summer.  The sound of splashing, buckets dumping, and children laughing with glee.  It is a sound that has become synonymous with summer, synonymous with fun, synonymous with childhood.  It allows children of all ages, regardless of their swimming proficiency – or lack thereof – to enjoy the water.

But behind this laughter and children splashing each other and spraying each other lies an ever-present risk.  Cryptosporidium.  Giardia.  Naegleria Fowleri.  Illness.  Sometimes mild, sometimes severely ill, sometimes death draws near to our most innocent and our most vulnerable.  

In December 2024, CDC released an issue of the Morbidity and Mortality Weekly Report (MMWR) titled Waterborne Disease Outbreaks Associated with Splash Pads – United States, 1997-2022.   This represents the first epidemiological study of waterborne diseases associated with Interactive Water Features (aka splash pads).  In this report, we find 60 outbreaks​ in 23 states and Puerto Rico.  To break the report down further, we see:

• 10,611 individual cases​

• 152 hospitalizations​

• 99 ER visits

• 40 outbreaks (67%) confirmed as Cryptosporidium​

• 2 outbreaks confirmed Norovirus​

• 5 outbreaks were Shigella related​

• 3 outbreaks were E.Coli related​

• Giardia, Norovirus, Salmonella, & Campylobacter caused 1 outbreak each​

• Legionella and Chloramines caused 1 outbreak each

• 95% of outbreaks were reported from May-August​

• 65% of outbreaks were reported from only Interactive Water Play Features

• 73% of the 99 ER visits resulted from Norovirus from just 2 of the 60 outbreaks​

• ​81% of hospitalizations were related to Cryptosporidium

Of special interest is that, for the period and scope of data collected, there were no reported deaths.  Sadly, from 2023-2025 there were 2 fatalities associated with splash pads – both from Naegleria Fowleri (aka the brain eating amoeba).  Naegleria Fowleri is the baddest of the bad.  Thankfully, it’s rare with only 164 or so cases since the early 1960’s.  But let’s put Naegleria Fowleri in perspective.  One of the most dreaded diseases on our big, blue planet orbiting a very ordinary yellow star is the Marburg Virus.  Marburg is Ebola’s bigger, scarier brother.  Marburg death rates range from an average of 50% and a range up to 90%.  Naegleria Fowleri?  The average death rate is 97.9%.

Let’s close Pandora’s Box for a moment and move back to the MMWR report.  There were four areas identified as contributing causes:

Maintenance (26 cases documented w/ 17 suspected).  These splash pads were most commonly found with malfunctioning, inadequate, or even lacking automated controllers and chemical feed systems.

Policies and Management (21 cases documented w/ 6 suspected).  Most commonly found was that the splash pads were tested infrequently – if at all.

Person (14 documented cases w/ 21 suspected).  The most commonly reported factor should come to no surprise – the splash pads were intended for use with diaper age children.

Facility Design (7 documented w/ 2 suspected).  These splash pads lacked a key component in protecting children – a Secondary Treatment system rated to inactivate 99.9% of Cryptosporidium per pass.

Can you see the theme?  High risk users.  Bad facility design.  Bad policies and practices.  Bad equipment.   That’s about 3 “bads” too many for an aquatic venue that serves our most innocent, our most vulnerable.  We can do better.  You can do better.  Our communities deserve better.  Our precious little ones deserve better.

So how do we do better?  The answer is surprisingly simple.

• Have properly functioning Automated Controllers and properly sized disinfection feed and pH control systems ​

• ​Perform Chlorine and pH testing every 2-4 hours with a FAS-DPD or DPD based test kit for chlorine, that is properly performed with reagents that are in date and properly stored​

• ​Install a properly sized NSF-50 Cryptosporidium certified Secondary Treatment system that treats 100% of flow​

• ​Create policies that are protective of bathers – especially vulnerable children

Let’s revisit Pandora’s Box for a moment and crack the lid a bit.  Naegleri Fowleri?  For its bluster and severe bite, it’s a simple solution.  Before opening for the season, while you’re cleaning and starting up the splash pad, plan on hyperchlorination.  Just go ahead and “nuke” it like you have Crypto in the water.   Those water tanks and piping that have been sitting dormant all winter?  It can use a good dose of hyperchlorination anyway.  As far as controlling the daily threat?  The generally recognized Concentration Time (the time it takes 1 ppm of Chlorine to inactivate a pathogen) is 9 minutes.  Keep an adequate sanitizer level at a pH of 7.0 to 7.5.

For our owners, I say do better.  Our children’s very lives are in your hands. If you’re going to build this type of venue – allocate the dollars to do it right.

For our designers, I see too many splash pad systems that are haphazard.  Thrown together on a shoestring budget.  Built to fit in a shipping container.  Designed without serious thought to the risk at hand.  For our designers, I say do better.  Our children rely on you to give the operators a fighting chance to save their lives.

For our aquatics leaders responsible for the day to day operation, I say do better. Be the protective voice of our children through understanding exactly what the risks are.  Don’t take shortcuts.  Test extra diligently.  Give splash pads the same serious approach you do drowning prevention.  Our children trust in you to keep them safe.

To read the MMWR report on splash pads, see https://www.cdc.gov/mmwr/volumes/73/ss/ss7308a1.htm

To learn more about CDC recommendations surrounding splash pads, see https://www.cdc.gov/healthy-swimming/safety/stay-healthy-at-splash-pads.html.  

Photo courtesy of Williamson County (TN) Parks and Recreation

Dewey’s Short Bio:

Dewey is the Technical Director for the Council for the Model Aquatic Health Code.   Additionally, he is the Aquatics Coordinator for Williamson County (TN) Parks and Recreation. 

His career started as a part time lifeguard, evolved into servicing pools, then began managing aquatic facilities while in college.  He has served in various roles with the YMCA of the USA, the local and state chapters of the American Red Cross, on the Lifeguarding and Bather Supervision Technical Committee for the MAHC 1^st Edition, and on the Technical Review Committee for the MAHC 3^rd Edition, as well as managing various aquatics facilities in the public, private, and non-profit sectors three decades.  He holds multiple Instructor Trainer certifications from the American Red Cross, as well as instructor credentials with the Pool and Hot Tub Alliance.