Index: /trunk/src/org/openstreetmap/josm/data/validation/tests/UnconnectedWays.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/data/validation/tests/UnconnectedWays.java	(revision 17926)
+++ /trunk/src/org/openstreetmap/josm/data/validation/tests/UnconnectedWays.java	(revision 17927)
@@ -144,5 +144,5 @@
         @Override
         protected boolean isCandidate(OsmPrimitive p) {
-            return p.hasKey("waterway");
+            return p.hasTagDifferent("waterway", "dam", "lock_gate", "weir");
         }
     }