What was found
(CAN) EN-ROUTE THE CREW EXPERIENCED A LOSS OF HYDRAULIC FLUID IN THE NR 1 SYSTEM. THEY ELECTED TO DIVERT AS A PRECAUTION. DURING THE APPROACH, THE NR 1 FLUID LEVEL DECAYED TO 25% SO THE CREW REQUESTED EMERGENCY SERVICES AND LANDED WITHOUT INCIDENT. THE NR 1 HYDRAULIC ENGINE DRIVEN PUMP WAS REPLACED IN ACCORDANCE WITH AMM 29-11-01. THE RETURN TO SERVICE WAS CONDUCTED. AS PER THE AMM 29-10-00, THE HYDRAULIC SYSTEM WAS FLUSHED AND THE AIRCRAFT WAS RETURNED TO SERVICE.