[HangnJudge]

he water is rising so fast I cannot begin to describe how quickly it's rising
cm per second might be a good bet

Last estimate I saw was about an inch every 5 min. at it's worst

[bobdsmith]

that's a lot faster than I expected!

[patricktschetter]

Last estimate I saw was about an inch every 5 min. at it's worst

That's a foot an hour! Assuming 80% of the city is covered with the same, rising water level, and an area of 180 square miles (I got that from here), that's 92,160 acre-feet per hour, 25.6 ac-ft/sec, or 1.11 million cubic feet per second. Yikes.