If this aerial photo is accurate, then the reactor complex is directly adjacent to the Pacific Ocean - for all practical purposes an infinite supply of seawater.

http://www.imgstant.com/-open-channel-blog-2007-japan-quake-was-wake-up-call-on-nuclear-safety-474x500/msnbcmedia2.msn.com%7Ci%7CMSNBC%7CComponents%7CInteractives%7C_swf%7CNews%7Cjapan_quake_2011%7CFukushima-Daiichi-Nuclear-Power-Station2.jpg/

Problems of lack of water must be very local lack of means to pump enough water to the places where it would do the most good.

If the proximity of the ocean is a given, I would have thought ship based pump and power systems would have been deployed. I can only guess the magnitude of the need exceded such straightforward solutions. [Shudder.]

Some problems with just adding water when the temperatures are too high:

Steam explosions. Happens if you heat water very rapidly in an enclosed cavity. Water and very hot metal is a very volatile mix if the rapid expansion of steam has nowhere to go. (I remember that one liter of water would turn into 1200 liters of steam in an instant if you put it in direct contact with molten metal).


Steam will have to be vented to the outside air. Hopefully, the steam itself won't bee too radioactive (at least not for too long) and hopefully it won't drag highly radioactive aerosols (particles small enough to be airborne) with it


Chemical reactions between the water and components in the reactor control rods and/or fuel rods that leads to formation of hydrogen. Mixed with oxygen it is very explosive. There has already been several hydrogen explosions, if I am not mistaken.

Complex Systems (hopefully) fail in complex ways.

There's a LOT of problems with adding water to fuel rods that are already very hot. It will definitely cause oxidation reactions with both the zirconium and uranium (the casing and fuel in the rods). These generate further heat. It could also cause some formation of hydrogen, which causes subsequent explosions. That has already happened several times. And if the rods get VERY hot, the process of hitting them with cold water might even crack the outside casings - releasing pellets of uranium (which would tend to settle by sinking to a lower level).

These are not my thoughts - they came from a buddy at work who was in the nuclear industry. I just talked to him this morning.

BUT with all that being said ... my friend still thinks the best thing is to flood the exposed rods with lots of seawater. And i assume that the Japanese are still working on this option. The trouble is - they are facing one of the biggest challenges in Engineering Emergency Operations in the last decade. Let's see how they handle it.

other Pete

As I understand they are very close to having a line which will provide electric power to the main pumps. This is the only long term solution in my opinion (which means darn little). The main pumps will get the water moving where it needs to be.