the 65 years of record-keeping

Yes, but you need 'the' before lowest, so : Faced with the lowest snow level in the Sierra Nevada mountains in 65 years of record-keeping, the governor felt he had no choice.

I don't think that's what he's asking, Ionus, but, you're right, "the" needs to be placed before "lowest," and it's not really "optional."



You could put "the" before 65, but, if you did, I think it would be better to rephrase the entire thing slightly. For instance:

" recorded in the 65 years during which records have been kept"

To me, "the 65 years" just doesn't seem to go well with "of record keeping" in this sentence.

It might be a way of designating a time period.

Example:

In the four years of marriage, he never kissed her.

Tired of waiting, he called her for the third time.

This is the 25th anniversary of the games.

Those are three different things, and only in the first is 'the' optional.

Thank you.

That is an abbreviation for journalistic reasons: it is not a proper sentence.

But you shouldn't put "the" before 65. It is not required.
It would only be appropriate if the 65 years period had already been referred to.

Thank you.
Thank you.