EMB ERJ 170/175 ER/LR
Flight Crew Air Transport Pilot (ATP)
Flight Crew Type 6000
Communication Breakdown
ATC Issue All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Fuel Issue; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Issued New Clearance
Human Factors
Working [a flight to] ORD we were given a lengthy re-route due to a storm system that was passing thru the Midwest. After a two hour ground stop clearance gave a re-route that added a considerable amount of time and distance to our originally planned route. I had spoken to Dispatch and we decided to add more fuel in case of holding and/or a long re-route. We decided on 9500lbs of fuel. Once the ground stop ended we were given a re-route by clearance of ZZZ.DQN.ENL.SPI and then the arrival. After reading back the route to clearance we put it in the FMS and sent it to Dispatch. We got our numbers and took off. I clearly remember telling my FO that the route was taking us almost to STL before turning north to O'Hare and I was surprised that we were going that far around the storm. Upon reaching the ENL VORTAC we turned towards SPI and the controller asked where we were going. I told her we were going to SPI as filed and she replied that our clearance was to STL after ENL. I told her we were not given that and we did not have the fuel for it. She said she was about to hand us off and to work it out with the next controller. Upon changing the frequency we were asked again where we were going. He sounded very busy and frustrated. I explained that we were flying the route we were given and that no one at any point in time ever gave us STL in our re-route and if they would have it would have required us to get another 2000lbs of fuel. He then cleared us to a fix on the arrival and the rest of the flight was uneventful. I am very surprised that a course deviation was filed because we flew exactly what was given to us on the clearance. ATC was clearly saturated and overtasked and if STL was supposed to be on our route it was never relayed to us. We flew the route we were given. It seems that somewhere along the way ATC decided to start routing aircraft over STL but failed to notify us of the change. I am 100% certain that STL was never in our route because we did not have the fuel to fly that far west before turning to ORD. I clearly remember thinking and commenting to my FO that we were ALMOST going to STL before turning to ORD and we talked about it. The bottom line is STL was not on our re-route or ever given to us by ATC. I apologize that this happened but I'm not sure what else we could have done different.
ERJ-170 Captain reported confusion on what route they were cleared to fly to ORD.