A fractured carbonate formation in the Egyptian eastern desert was saturated with heavy oil, the hydrocarbons having migrated up from deeper source rock. Water breakthrough was beginning to occur with ingress suspected at several levels. Scimitar determined that the completion system had to allow simultaneous logging and pumping, resulting in the implementation of a creative production scheme needed to solve the issues with water breakthrough. ESPs were equipped with a Y-tool bypass system that was made up of a concentric through-tube so that the logging tool string could pass the pump and enter the completion zones beneath it. The Y-tool completion allowed excellent dynamic and drawdown conditions to be established so that downhole conditions could be diagnosed. The combination of high-volume ESPs with accurate flow analysis using a multisensor production logging tool in both static and dynamic flow conditions effectively solved the evaluation challenges and led to a practical solution to field production challenges.