This has been on my mind for a couple of years. Although there are reams of info on kayaking in cold water, I cannot find much on rising water temperatures. I live in east central Illinois. It is not the hottest place in the U.S., but it has a fair amount of hot and humid days (over 95 and extreme humidity giving a ‘realfeel’ of +105 F) that are increasing. What I’ve noticed (I kayak solo at the crack of dawn) are rising water temperatures, coinciding with higher lows in the early mornings. Here we have rivers and lakes. I kayak a lot on the central CA coast, so I notice the hot water here in IL; and in the morning now the water is warmer than the air (e.g. a spring fed lake I kayaked on yesterday had an air temperature of 72 and a surface water temperature of 84 at 7 am). So I’ve included a USGA image of another nearby lake and yes, it’s getting up to 90F! So I want to know what the conditions are that promote various amoeba/bacteria/viruses, etc. in warm water (I do avoid geese infested waters). Just like I don’t kayak on flooded, chocolate rivers, or below 30F or during a thunderstorm, I’m starting to stay at home because the water is not cooling much overnight. Am I being too cautious? I am having difficulties getting factual information about this.