2 hours and 28 minutes. According to Baidu map, Yishui and Zibo are176.2km apart, and it takes 2 hours and 28 minutes to drive. Specific bus routes:

1. Take a taxi from Yishui to Yishui Station first.

2. Secondly, take the high-speed train at Lishui Station.

3. Finally, it takes 3 hours 16 minutes to reach the destination.