Index: trunk/src/org/openstreetmap/josm/data/validation/tests/PowerLines.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/validation/tests/PowerLines.java	(revision 18837)
+++ trunk/src/org/openstreetmap/josm/data/validation/tests/PowerLines.java	(revision 18838)
@@ -629,5 +629,5 @@
      */
     private static boolean concernsWaterArea(OsmPrimitive p) {
-        return p.hasTag("water", "river", "lake") || p.hasKey("waterway") || p.hasTag("natural", "coastline");
+        return (p.hasTag("water", "river", "lake") || p.hasKey("waterway") || p.hasTag("natural", "coastline")) && p.concernsArea();
     }