Flood Mitigation and stuff to do in preparation. An Expat Plumbers perspective.

EVEN AS I TYPE THESE WORDS there are these black tar-like, massively polluted, disease infested flood waters making their slow, deliberate, terrifying and somewhat ominous, silent advance on Asok, Bangkok. We never thought it would happen to us, we were told we'd be safe. Turns our this was just a game of save-face by the hi-so billionaire club.

To put it mildly, I'm a tad concerned. Not through of fear of drowning, or running out of super noodles, but because I'm very worried about the immediate sickness, financial devastation and long term physiological damage that these waters bring with them to the common people.
This post will hopefully help all you good people to fair better in these difficult times. Read my thoughts and take from them what you will. And the very Best of British to all of you.

It's  called a map Sire. It's  a bit like one of your drawings of Narnia, but without the superheros or unicorns.
Probably best if you don't try to set fire to it Sire. No, it doesn't float like a magic carpet M'lady.

From a PLUMBERS PERSPECTIVE here's what you can do to make things slightly easier for you if you haven't already been flooded but think there is a chance you will.

1. Flood water will totally ignore the sand bag walls and come up through the drains either side of the barriers. All drains are connected and lead to rivers and central sewage processing plants often tens of miles away. Fortunately, all drains flow down-stream towards the nearest river or processing plant. Unless you block off the drains either side of the sandbags with 100% watertight covers, the flood water will still rise. As most of the drains are open in Bangkok then the sand bags in an area with open drains on either side of the barriers are totally useless.
2. If you live in a ground floor apartment you might want to think about wrapping cling film over the top of your toilet, shower drain and basin overflows. Otherwise, even if you manage to sand bag/barricade the water out of your apartment, once the water pressure in the external drains overcomes the air pressure in the u-bend and overflow traps it will flush all the muck in the drains back up through your toilet and sink/basin overflows. This can be quite a rapid, messy and violent affair as I'm sure you can imagine.
3. Fill as many buckets as you can afford with tap water,  squirt 4 drops per litre of 7/11 iodine into the water and wrap cling film over the top. You can drink this if you run out of water and the tap water tuns brown - which it probably will.
4. Monitor the local mains water NOT the tap water. Do this by checking water from an out door tap (assuming it is running straight off the mains and not your storage tanks). If it starts turning cloudy run up to to the roof and TURN OFF the mains supply (probably a ball cock) that tops up the tanks. Ration this water. Coordinate the rationing with other members of your building and if necessary BE STRICT. There is a small probability that some locals will not understand what you are trying to do and will think you are being a mean and horrible Farang. Be patient and explain slowly in your best Thai that you come in peace. Use crayons and colored paper if necessary. You may get asked for money or cigarettes. Hand out sweets and flowers instead.
5. Don't panic and start acting like Tom Cruise in War of the Worlds when the water arrives. If you don't think you can hack it, get out while you still can. The only reason I'm sticking around is because I live on the eighteenth floor and have stockpiled around seventy gallons of drinking water, nine hundred packets of instant noodles and enough cheese to last your average German a minimum of five years.