Aua dil Mer is actually the name of the river of the waterfall Aua dil Mer wasserfall, an unofficial named waterfall near Pigniu in the region Graubünden, Switzerland.
The waterfall is located at the shore of the Panixersee (Lag da Pigniu). The Panixersee is easy to reach from Pigniu, a hike of 6 kilometer. It is also possible to drive all the way up to the dam at the Panixersee and park your car there (gps 46.823601, 9.111329). From here it is a 1,5 kilometer walk along the shore of the lake to a viewpoint on Aua dil Mer.
At the north side of the Panixersee two rivers flows into the lake: The Schmuer and Aua dil Mer. Both have nice waterfalls and can be both very powerful. What I can see that there is another waterfall next to the Aua dil Mer.