EMB ERJ 135 ER/LR
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Aircraft Equipment Problem Less Severe; Inflight Event / Encounter Fuel Issue
Flight Crew Landed As Precaution; Flight Crew Returned To Departure Airport; General Maintenance Action
Aircraft; Environment - Non Weather Related
During our enroute climb out I noticed the yellow dashes briefly appeared on the fuel quantity gauge on the MFD (Multi-function Display). After the dashes cleared I noticed an irregularity with the fuel quantity indication showing lower than required. My FO (First Officer) stated that he had this issue before but couldn't remember what aircraft; that combined with a fuel leak issue we had earlier in the day with the same aircraft led us to the decision to not take any chances and return to [departure airport] to sort the issue out on the ground. We did not [advise ATC] but asked for no delay in returning to the airport. We landed without incident and taxied to the ramp. I coordinated with Maintenance Control who called onsite maintenance to come troubleshoot the issue. Upon arrival I described the issue to the mechanic who stated 'We have actually had numerous fuel gauge or quantity issues this past week due to the heat and fuel contamination. We should sump the tanks and see what we find.' I agreed and the mechanic did sump the tanks and did find approximately 1 cup of water after the sumping was complete. The mechanic then added that with the finding of water in the system; the amount they found was enough where it very well could have led to the erroneous indication issue we saw. I refueled the aircraft and monitored the fueling in person to ensure no contamination was present and quantity was correct on all available instrumentation. Upon receiving the all clear from the mechanic and Maintenance Control we then took off and completed the flight without further disruption.
EMB-135 Captain reported returning to departure airport following fuel quantity display anomalies due to fuel contamination.