Boil Water

The Boston area had a water main break on Saturday morning. It's the really big pipe (10 feet diameter) that comes from the west and feeds treated tap water to Boston and surrounding suburbs. While fixing it, they switched over to emergency reservoir supplies which isn't treated, so it's fine flush, shower and put out fires; but it is not safe to drink. Details here and I won't try to repeat all the cautions.

Instructions are to boil water for at least minute before using to drink or to rinse produce to be consumed raw and to rinse dishes in a bleach solution after washing with tap water. Restaurants are having a hard time and this chowhound thread describes some stories.

So I'm curious if anyone knows details. I'm assuming the emergency water just isn't known to be safe. There are safety standards that must talk about contaminants as parts per million or something like that. I heard an MWRA representative interviewed on Sunday and she said that the issue would be parasites and that symptoms would be gastrointestinal distress and wouldn't show up for a week.

So my real question is, is it really important to boil water for a minute to kill anything? I thought that 165°F was thought to be enough to kill lifeforms and that a few exotic species have recently been found at 170° or so around undersea volcanoes.

I'm assuming that instructions to boil for a minute are in part because they are easy to follow and know. It's hard to tell someone to get the water to 190°F because how would they know without a thermometer? It's easy to say a rolling boil and it's easy to say for a minute to make sure it really is boiling. But the chowhound thread was complaining about using industrial coffee makers at 190°F saying that's not enough to kill bacteria.

Then again I know for canning you're supposed to boil jars for 10 mins. foodsafetysite says at 165°F "Most bacteria die; some spore-forming bacteria survive" but 212°F doesn't kill botulinum spores, you need 250°F for that, so I'm guessing we're not worried about them in our emergency water supplies.

So, does anyone know the details?