"When could all this happen? In 10, 20, 50 years?...“No one really knows,” Lemmo said. There are too many variables."

Agree.

"The flooding caused by rising groundwater and other factors could threaten $5 billion of taxable real estate and flood nearly 30 miles of roadway, the study concluded."

That might be true if this theoretical flooding occurred overnight, but just as low lying area property dwellers have done for centuries, relocation will be a gradual process, as needed. The city and state, on the other hand, cannot even maintain their real estate and roadways in current time, so in that "no one really knows" future, look out - maybe.