1. Drank a gallon of liquid (could have been water or sports drink, I don't remember) on that ~3 hour ride.
2. Didn't pee until I got home -- and not much then.
3. Came home with dry clothes, despite (obviously) sweating something like a gallon of liquid. There was no evidence of sweat, ever -- it all evaporated.The recommended amount depends on who does the recommendation but 1.9L doesn't seem high.
https://www.efsa.europa.eu/fr/efsajournal/pub/1459
"Adequate Intakes (AI) have been defined derived from a combination of observed intakes in population groups with desirable osmolarity values of urine and desirable water volumes per energy unit consumed. The reference values for total water intake include water from drinking water, beverages of all kind, and from food moisture and only apply to conditions of moderate environmental temperature and moderate physical activity levels (PAL 1.6). [...] Available data for adults permit the definition of AIs as 2.0 L/day (P 95 3.1 L) for females and 2.5 L/day (P95 4.0 L) for males."
https://apps.who.int/iris/handle/10665/43403
"The minimum water requirement for fluid replacement for a 70kg human in a temperate zone equates to 3L per day, or 42.9mL/kg [according to the Tropical Agriculture Association]. Minimum requirements for an individual the same size but in a tropical zone equates to 4.1 to 6L/day"
"Age and gender specific Adequate Intakes (AI) for water were established in 2004 by the [United States] Food and Nutrition Board (5). The Dietary Reference Intakes (DRI) for water are [for ages 19 and older] Men 3.7 L/day Women 2.7 L/day"
One stop every 2 hours to chuck 500ml of beer (Bia Hanoi, pretty nice light blond), so about 4 stops a day. It worked fine ! Pee was ok color, enough tipsy to keep my sense but numb the pain of cycling. My clothes had aureola of salt and urea.
I also find the amount questionable, as I suspect that our modern expectations of what that means and the details of what they meant when they recorded personal consumption means there's something lost in translation here.
Even when I was outside scouting crops 10-12 hours a day on foot in southwest kansas with peak 110F temps, I'd still not need to drink more than 4 liters of water a day. I could push it up another liter, but it wasn't needed and could actually be harmful if one overhydrates. And that's the extreme of the year, way more what I'd reach for most of the year.
Whereas the daily motto of the fuckers was apparently "I am a machine that turns beer into piss"