Has anyone recently arrived for a river cruise only to find it turned into a bus tour due to low river levels??

I haven't but it isn't unheard of. There have been a couple of trip reports about river trips that became wholly or partly land tours.

Please specify which river and what time of year.

Wondering about the Elbe River and current condition

Here are the river levels of the Elbe:

https://www.elwis.de/gewaesserkunde/...ml.php?gw=ELBE

You see, they are extremely low by now and they will even fall.

Here is a picture from July:

http://www.t-online.de/regionales/id...lematisch.html

If water level is too low for sailing the passengers will we transported by bus to the ports of call and you will sleep in hotels.

http://rivercruiseinfo.com/content/river-levels

It happened to us a few years ago on the RHINE. It was a Viking river cruise, and Viking did their best to make a go of it, and put us up in 5 star hotels wherever they could. But it still was more of a bus tour than a river cruise.

The Rhine is well known for low levels and the cruise company will not let you know in advance what they are planning, so do as traveller1959 suggests, which is to do your own research and demand answers from the cruise company.

traveller, you give great Germany