you're mis-reading the history there. Water was diverted into the area to use as irrigation for farming, at this point there was no sea nor was anything on that scale intended.
It wasn't until the heavy rains and unintentional diversion of the Colorado that the sea formed.
It didn't start as an accident, there was a prehistoric lake there, occasionally inhabited. Because of the lake that used to be there the area has fertile soil. Humans diverted water there intentionally for farming. Some people profited off of this and have left residents and others to deal with health effects and pick up the tab of dealing with the problem.
Some people profited and while they did so, they incidentaly did everyone a favor by preventing the harms that mother nature would do in their absence.
IF not for the accident, most of the lake wouldn't exist as it does today.