Dont you think sirens would have helped? Honest question. Because if you think they would have improved the odds of survival even 10% then there is blame to assign I am sorry.
As for being near a river maybe Texas should actually read their Bibles:
"Therefore everyone who hears these words of mine and puts them into practice is like a wise man who built his house on the rock. 25 The rain came down, the streams rose, and the winds blew and beat against that house; yet it did not fall, because it had its foundation on the rock. 26 But everyone who hears these words of mine and does not put them into practice is like a foolish man who built his house on sand. 27 The rain came down, the streams rose, and the winds blew and beat against that house, and it fell with a great crash.”
-Matthew 7:24-27