Dunno, but looks odd.
At 2:08 to 2:20 of vid maggief posted:
https://www.facebook.com/KCRA3/videos/vb.115763581513/10155031720176514/?type=3&theater
Daniel,
Your thoughts on what the dark spot is?
Good question.
bbl
https://m.youtube.com/watch?v=Bd1Euy1-sBs&feature=youtu.be
Engineer interview: “Stay the hell out of Oroville.”
https://www.youtube.com/watch?v=dAuYuyCcYB8
White Spots on Oroville Dam. Rising air?