NEFA DISCussion

so, you're playing a new course you've never played before.

The tee signs are very detailed, depicting that there are (and where) water hazards between the tee and basket.

but none are labeled as OB nor Casual.

You land in the water (or even on the opposite side of the stream/river/pond)

OB?

A hazard that is not marked OB would just be a hazard.

All water is casual unless designated otherwise. If it's not labeled as OB or non-casual, feel free to play it as casual.

800.02 Definitions
Casual Water
A body of water which is not out-of-bounds, and which has not been declared by the Director to not be casual water.

Of course if you're playing the course in a non-tournament, non-league setting, you can do whatever you want. If you want to play the water as OB, go for it.