As luck would have it I live in one on the 13 lowest districts of Bangkok. A big 'mooban' towards the outer part of Ramkhamhaeng Rd.
So our house looks like a scene from my basic training days. Sand bags everywhere and a pump in the ready. Yes, our soi does flood from time to time but this one may be just a bit different.
Check out this website.
http://map.longdo.com/
I do not have the time to explain everything, but it shows where the water is going. This is a Thai site but there is an English version.
At least my wife bought a 3-person boat a couple of weeks ago.Come to think of it the only people staying here other than me is my wife, daughter and MIL...