One problem related to water pump has been reported for the 1997 Buick Park Avenue. The most recently reported issues are listed below.
Heater/air conditioning leaks onto floor on the passenger side of vehicle. Started about a year after purchase (new) and we complained. Dealership replaced water pump. Still leaked. Became much worse in July 2003 (required a roll of paper towels to keep the front floor board semi dry on trips). We took it to fitzpatrick in concord, CA and they stated that all gm vehicles did that and there was no repair needed. This was when the car was still under warranty and now, no longer is.