Quote:
Originally Posted by christiangirl
Can someone please explain why the buildings are that far underwater if there was only 18" of rain? Is part of it from the rivers washing over? I'm not from an area that floods much, so forgive me.
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Here's my best explanation:
So everywhere is getting 12-18" but that includes areas that are parking lots, covered by buildings, etc. In other words, for every square inch of rain fall there is not one square inch of ground for it to soak into. Even if the rain did land in a dirt/soil areas those can not accomadate that much water in every square inch.
Therefore, you get the run-off effect. Initially the water will run into drainage ditches. However, drainage ditches are not designed to hold that amount of running water so they over flow. The water that makes its way into the ditch is dumped into small creeks. Same scenario with the creeks: they just aren't designed for that much water, so MORE overflow. The creeks dump into tributaries, the tributaries into the Cumberland. You get the idea. Just nowhere for all that run-off water to go. Also, rain that falls fast runs off more than slow steady rains. My firends said the rain was so hard and so fast that being in their houses on Saturday sounded like being in a car wash. All Day Long.
This is why the neighborhoods flooded first, on Saturday. It took 2 days for all the tributaries to dump into the Cumberland which crested last night. Thus, downtown and the Opry area (further down river from downtown) did not flood until yesterday.
Entire neighborhoods are under water and since those areas were never declared flood plains those homeowners did not have flood insurance.
Looks like there has been slightly more attention given to the situation on tonight's news, but the above poster who mentioned that more has been covered via Facebook is 100% correct.