I have heard of impeller failures, but that is too early.

Was it a bearing problem, or a leaking seal (which is often a result of a bearing failure)? If so, I would wonder about belt tension, a frequent cause of water pump failures on other models. There is a tensioner on your belt, but conceivably there could be a problem. Just guessing.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue