Monkey Wrench Firmly Inserted

I was called in recently to review plans for a cooling system for a large variable frequency drive. Sparkys (Electrical Engineers to the lay man) have been working on this for months, both here and across the pond in Deutschland. The cooling system uses de-ionized water which is pumped around the circuits and out to a fin fan cooler located outside the building. It will be located offshore Louisiana. After a short review, I asked the question:

"How do you prevent the cooling water from freezing in the winter?"

Dead silence. Deer in the Headlights looks all around. It never occurred to the ohhh so detail oriented Germans that the air temperature in the GOM can get below freezing, but it can. And the design basis required low temperature operation as well. Sparkys are now scrambling to retrofit a fix.