Wow, an ad hominem attack on engineering? That's a very special take to have on a site calles HACKER news!
Would you prefer we'd suffer nature and never attempt anything? That's not very hackish :)
Whether we like it or not, the Mississippi is sending a lot of clearwater down the gulf of Mexico, water that is needed elsewhere. The plan makes sense- and not just for the most visible parts like the Hoover dam.
Nothing is without risk: the risk of doing nothing may be more to your liking, but there will also be consequences, and some people will suffer. Of course, by doing nothing you may try to avoid personal blame - but it's akin to a trolley problem, and inaction can be morally guilty if you believe in utilitarianism.
IMHO the most important thing to do is to honestly study all the alternatives (including inaction) then choosing the one that makes the more sense - yes, even if it's action, and even if there may be some prejudice against engineering, or a bad precedent (that can and should be taken into account in the honest study)