diff --git a/DataStructures/ImportEdge.h b/DataStructures/ImportEdge.h
index 27d7fa9e0..61190d056 100644
--- a/DataStructures/ImportEdge.h
+++ b/DataStructures/ImportEdge.h
@@ -118,9 +118,9 @@ public:
     NodeID _source;
     NodeID _target;
     NodeID _edgeID;
-    EdgeWeight _weight;
-    bool _forward;
-    bool _backward;
+    EdgeWeight _weight:30;
+    bool _forward:1;
+    bool _backward:1;
 };
 
 struct MinimalEdgeData {