I may be a bit dense here, but you are going to have to ellaborate a bit more on your thinking.
A real water crisis means that there is not enough water to go around. As opposed to a potential or fabricated water crisis.
If people aren't getting enough to eat or drink, then eveyone becomes an activist.
I just don't see how this has anything to do with radical environmental activists. It seems to me that these are reasonable scientists saying that if you empty the glass faster than it is refilled, eventually there won't be enough to drink.
The interesting spot to watch is China moving into the Russian held Mongolia and Siberia eventually as their water supply dwindles. It appears they are attempting to co-opt that territory by attrition since Chinese are moving into it.
I think that could be a major flashpoint in this century.