Some & rough waters ?

Hello~ what do you think the meanings of the words "some" and "rough waters" are in this context?

Thanks~

During that session, teachers in attendance lamented the fact that
they had to teach students who had discipline problems and did not want
to learn. Their suggestion to the school board was for the administration
to create more alternative schools. The sentiment was, “ . . . those kids are
a distraction for the students who want to learn.” I distinctly remember
one courageous first-year teacher in the room who tried to turn the conversation
to teacher accountability and their responsibility for educating
all children. She was met with a resounding rebuke from her more senior
peers. The stark reality of this disturbing culture was like a slap in the face
for me. Bill Daggett from the International Center for Leadership in
Education has frequently stated that “culture trumps strategy.” I realized
changing the culture and steering this ship on a course that embraces
equity and diversity while maintaining excellence was going to agitate
some already rough waters. And any public discussion about race was
going to be very risky.