water doesn’t specifically cause organ damage in and of itself, but it is possible to basically dilute your body’s ion content by drinking too much in a short period (or else, by not urinating enough for one reason or another, including certain kidney issues). This condition is called hyponatremia (“low sodium”, basically), because the main issue is the blood becoming dilute enough that sodium has trouble reaching the nervous system in the amounts it requires, and this leads to a variety of primarily neurological symptoms (headaches, nausea, poor balance, confusion, and in severe cases seizures and coma), which can somewhat resemble drunkenness, hence the popular (but sort of inaccurate) term “water intoxication”.

Luckily, in most cases it resolves on its own without too much trouble, and only very rarely becomes actually life-threatening. The one thing you have to watch out for with it is that the symptoms can actually sometimes be mistaken for dehydration, which can obviously lead to more water consumption, and a worsening of symptoms (the sign to look out for is whether ones urine is dark-colored or totally clear). Drinking electrolyte drink mixes can help prevent hyponatremia.

So basically, no (realistic) amount of water is bad for most of your organs, except arguably your nervous system under extreme and fairly unusual circumstances. But in general, there’s no such thing as “too much water” on a habitual level.