Readings & Meanings:
We have decided to preserve these writings forever.
After a long, protracted fight against the disease, he finally passed into eternal sleep.
I hope that this is the beginning of a long friendship.
水 = water.
That's what I think of when I look at this kanji. Water. And then I look at the top, and see that little piece jutting off, and then I know it's 永, meaning eternal.
When reaching for an explanation, I think of the Greek idea "Nothing eternal but change," which comes packaged with the idea of a river: the river changes, but it is always the same while always changing.
When we reach back into the origins of this kanji, we get the idea of water splitting into many rivers. The length and breadth of the many tributaries of the rivers is too great to measure with your eyes. 永's thought concept is that an eternal amount of time is immeasurable, like trying to measure the amount of water in a river and its divisions.
Please do not confuse 永 (forever) with 氷 (ice).
永 has two splits at the top of 水, signifying many rivers splitting off.
氷 has only one chip of ice on the left. And is delicious in the summer as かき氷.