Relief mathematics

One of the things that struck me about the recent coverage of the Haiti earthquake was the movement of an aircraft carrier, the USS Carl Vinson to the region. It will be desalinating seawater to aid relief efforts. This made me wonder, how many people can an aircraft carrier actually keep alive? It can apparently produce 400,000 gallons of water a day, of which it requires 75% for internal use, and is therefore able to provide 100,000 gallons a day to Port-au-Prince. So how many people does that keep alive?

The average human needs 80 ounces of water daily to stave off dehydration and death, 1 gallon is 160 ounces. So the USS Carl Vinson can keep about 200,000 people alive indefinitely, or 300,000 if it produces 150,000 gallons excess according to some reports (I assume this means the crew going short or something similar). While completely laudable, the population of Port-au-Prince (excluding the surrounding area that is also affected) is somewhere between 2.5 and 3 million. So such carriers can keep 10% of the population alive, but what about the rest?

I am not being fatalistic when I say there are limits to what states can do in response to such events. Given the disposition of US aircraft carriers (there are 10 <i>Nimitz</i> class carriers in service worldwide), Haiti is relatively lucky to have one within a few days sailing distance, most other countries wouldn’t be reached so quickly. I think these events should give anyone who talks about physical distance “not mattering” in a globalised world pause for thought. With the correct equipment, information transmission is almost instantaneous. Unfortunately information doesn’t stop people from dying of hunger and thirst. When the dust settles in Haiti, I imagine there will be an almighty reckoning/finger pointing session, where states such as America and Britain will be subjected to accusations of “too little, too late”. I also think that politicians in an act of public contrition will probably agree, on camera, and most likely order a review or similar. But I think that such actions will mask a deeper, more troubling truth: there are limits to what states can do, especially at a distance. Importantly, those limits might much be lower than most people would expect of the developed world. Despite all the technological developments (carrier planes, floating nuclear reactors with water purification gear) keeping a city of 2.5 million people alive at the end of a runway might be beyond the ability of the international community. West Berlin had less people, 35 days of food stockpiles and an intact infrastructure before the Blockade, Port-au-Prince sadly has none of those factors in its favour.