The Ortlieb Esky

So we're going to Turk's Xmas party, naturally we are going to ride our bikes but what to do with the drinks.  We all know that Ortlieb panniers are the best panniers for keeping water 'out' so why wouldn't they be able to keep water 'in'?

My pannier had 12 beers and half a bag of ice, Sandy's two bottles of bubbly and the rest of the ice.  We parked the bikes under the house, leaving the panniers on.  There was still ice in them at the end of the night.