diff --git a/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataArray.java b/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataArray.java
index d469ff9dac9..54d4da17713 100644
--- a/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataArray.java
+++ b/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataArray.java
@@ -26,7 +26,7 @@
 
 /**
  * Implementation of {@link TravelTimeData} that stores the data per time bin
- * in simple arrays. Useful if not too many empty time bins (time bins with 
+ * in simple arrays. Useful if not too many empty time bins (time bins with
  * no traffic on a link) exist, so no memory is wasted.
  *
  * @author mrieser
@@ -58,10 +58,12 @@ class TravelTimeDataArray extends TravelTimeData {
 	 */
 	private final long[] data;
 	private final Link link;
+	private final double timeStepSize;
 
-	TravelTimeDataArray(final Link link, final int numSlots) {
+	TravelTimeDataArray(final Link link, final int numSlots, double qsimTimeStepSize) {
 		this.data = new long[numSlots];
 		this.link = link;
+		this.timeStepSize = qsimTimeStepSize;
 		resetTravelTimes();
 	}
 
@@ -107,14 +109,19 @@ public void addTravelTime(final int timeSlot, final double traveltime) {
 
 	@Override
 	public double getTravelTime(final int timeSlot, final double now) {
-		long val = this.data[timeSlot];
-		double ttime = traveltime(val);
-		if (ttime >= 0.0) return ttime; // negative values are invalid.
-
-		// ttime can only be <0 if it never accumulated anything, i.e. if cnt == 9, so just use freespeed
-		double freespeed = this.link.getLength() / this.link.getFreespeed(now);
-		this.data[timeSlot] = encode(0, freespeed);
-		return freespeed;
+        long val = this.data[timeSlot];
+        double ttime = traveltime(val);
+        if (ttime >= 0.0) return ttime; // negative values are invalid.
+
+        // ttime can only be <0 if it never accumulated anything, i.e. if cnt == 9, so just use freeSpeedTravelTime
+        double freeSpeedTravelTime = this.link.getLength() / this.link.getFreespeed(now);
+        if (timeStepSize > 0) {
+            freeSpeedTravelTime = (Math.floor(freeSpeedTravelTime / timeStepSize) + 1) * timeStepSize;
+            this.data[timeSlot] = encode(0, freeSpeedTravelTime);
+            return freeSpeedTravelTime;
+        }
+        this.data[timeSlot] = encode(0, freeSpeedTravelTime);
+        return freeSpeedTravelTime;
 	}
 
 	/* package-private for debugging */ String cntToString(){
diff --git a/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataArrayFactory.java b/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataArrayFactory.java
index db9b07a578c..80d94c7e0db 100644
--- a/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataArrayFactory.java
+++ b/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataArrayFactory.java
@@ -23,20 +23,29 @@
 import org.matsim.api.core.v01.Id;
 import org.matsim.api.core.v01.network.Link;
 import org.matsim.api.core.v01.network.Network;
+import org.matsim.core.config.groups.QSimConfigGroup;
 
-class TravelTimeDataArrayFactory implements TravelTimeDataFactory {
+public class TravelTimeDataArrayFactory implements TravelTimeDataFactory {
 
 	private final Network network;
 	private final int numSlots;
+	private final double qSimTimeStepSize;
 	
 	public TravelTimeDataArrayFactory(final Network network, final int numSlots) {
 		this.network = network;
 		this.numSlots = numSlots;
+		this.qSimTimeStepSize = -1.0;
+	}
+
+	public TravelTimeDataArrayFactory(final Network network, final int numSlots, QSimConfigGroup qSimConfigGroup) {
+		this.network = network;
+		this.numSlots = numSlots;
+		this.qSimTimeStepSize = qSimConfigGroup.getTimeStepSize();
 	}
 	
 	@Override
 	public TravelTimeData createTravelTimeData(Id<Link> linkId) {
-		return new TravelTimeDataArray(this.network.getLinks().get(linkId), this.numSlots);
+		return new TravelTimeDataArray(this.network.getLinks().get(linkId), this.numSlots, qSimTimeStepSize);
 	}
 
 }
diff --git a/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataFactory.java b/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataFactory.java
index fbe4aa0d726..4129542100f 100644
--- a/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataFactory.java
+++ b/matsim/src/main/java/org/matsim/core/trafficmonitoring/TravelTimeDataFactory.java
@@ -24,7 +24,7 @@
 import org.matsim.api.core.v01.network.Link;
 import org.matsim.core.api.internal.MatsimFactory;
 
-interface TravelTimeDataFactory extends MatsimFactory {
+public interface TravelTimeDataFactory extends MatsimFactory {
 	
 	public TravelTimeData createTravelTimeData(final Id<Link> linkId);
 
diff --git a/matsim/src/test/java/org/matsim/core/trafficmonitoring/TravelTimeDataArrayTest.java b/matsim/src/test/java/org/matsim/core/trafficmonitoring/TravelTimeDataArrayTest.java
index 53a1ab360c9..4f0d6f7daec 100644
--- a/matsim/src/test/java/org/matsim/core/trafficmonitoring/TravelTimeDataArrayTest.java
+++ b/matsim/src/test/java/org/matsim/core/trafficmonitoring/TravelTimeDataArrayTest.java
@@ -21,7 +21,7 @@ public void test() {
 		Node to = NetworkUtils.createNode( Id.createNodeId( "2" ) );
 		Link link = NetworkUtils.createLink( Id.createLinkId( "1-2" ), from, to, network, 10, 10, 10, 1 );
 		final int numSlots = 24;
-		TravelTimeDataArray abc = new TravelTimeDataArray( link, numSlots );
+		TravelTimeDataArray abc = new TravelTimeDataArray( link, numSlots, 1.0 );
 		log.info( abc.ttToString() );
 		log.info( abc.cntToString() );
 		abc.resetTravelTimes();