Cryptosporidium.

And Poo.

And sweat.

http://metro.co.uk/2015/06/27/swimming-pools-can-give-you-diarrhea-5269062/

And then there's what Americans do most:

http://metro.co.uk/2015/06/21/swimming-pool-chlorine-doesnt-make-your-eyes-red-sweat-and-urine-does-5256403/

See also:

http://metro.co.uk/2015/06/17/americans-most-likely-to-pee-in-the-pool-and-steal-toiletries-on-holiday-says-poll-5249484/

In some countries, patrons are actually expected to shower before entering recreational water.

 

In others, any such notices are universally ignored.

In the USA this was REQUIRED and RIGIDLY enforced at least through the Seventies.

Now, most waterparks don't even have sufficient facilities to allow such, and their locker facilities actively discourage it.

All things considered, it is safer to enjoy the relentless splashing of Whitewater Canyon, and the geyser-obsessed soakaholics therein (arrr, and so on so forth)...

 

The last time I was in a water park, a young couple very near by (it was so crowded, people kept bumping into one-another) started, well, doing that which cannot be concealed (a more deliberate kind of bumping), and I got out immediately. I've never gone back. Private pools from now on... and I don't spare the HTH.

Talk about swimming in toilets....yuck!

All things considered, it is safer to enjoy the relentless splashing of Whitewater Canyon, and the geyser-obsessed soakaholics therein (arrr, and so on so forth)...

 

The last time I was in a water park, a young couple very near by (it was so crowded, people kept bumping into one-another) started, well, doing that which cannot be concealed (a more deliberate kind of bumping), and I got out immediately. I've never gone back. Private pools from now on... and I don't spare the HTH.

We need an official KIC White Water Canyon geyser get-together. Imagine the fun that would ensue if we could get a large group of people, all experts at the cannon of their choice, to occupy every cannon and soak all the full boats we see with every. single. cannon. Such fun!

Of course, being the good sports that we all are, we would have to break it up frequently to allow others a chance to use the cannons, but I don't think anyone can complain if they need to wait a few minutes for us to get two or three good geyser blasts in.

^ Then we ride, bragging to the tower operator about hitting boats with every geyser. Right?

 

I'll not lie- my last visit to Soak City, I saw a woman take off her bandaid and wash away the pus from a sore on her ankle.

 

I can't do the public pool anymore. 

^^No just harass the ride op in the tower, or yell at him to soak another individual. Never fails.

Researchers measured the amount of urine in public swimming pools, finding that one pool contained 75L (20 gal) of it.

https://www.theguardian.com/science/2017/mar/01/how-much-pee-is-in-our-swimming-pools-new-urine-test-reveals-the-truth

Sounds cleaner to swim on the Ohio River. Which as a youngster I did quite often. I wouldn't recommend it now. 

The CDC released a report last month on employees and guests who were sickened at an Ohio indoor waterpark. The park in the report is not named, but the timing (2015 through early 2016) and circumstances (lack of working ventilation) are similar to the Fort Rapids incident. Disinfection byproducts were able to build up in the building and cause numerous symptoms.

The park was advised to fix the HVAC system and encourage swimmers to shower and "take regular bathroom breaks" (i.e. not to urinate in the pool).

https://www.theverge.com/2017/9/21/16345862/ohio-water-park-cdc-pee-chloramines-chlorine-eyes-lungs-irritation-mmwr