I see you are under the I-30 bridge on Lake Ray Hubbard.
The location should put you in the creek channel.
The sides of the channel rise quickly at least 5', so that explains the bright gold color.
I can't tell from my map if it tapers back deeper.
I think leeb's first choice is right.
I'm confused as my map shows a 40' channel and your image is 24'.
Mike