In this paper we propose new real time architectures for monitoring underwater oil and gas pipelines by using Underwater Wireless Sensor Network (UWSN). These new monitoring architectures combine a real time UWSN with nondestructive In Line Inspection (ILI) technology. Having a communication between UWSN and In Line Inspection tools adds a meaningful feature that allows the Underwater Wireless Sensor Network delivers the crucial information regarding pipeline failures in up to minutes. Currently, there is not an established communication system between Underwater Wireless/Wired Sensor Network and In Line Inspection Tools. Nowadays, the ILI tool has proven invaluable for inspecting extensive pipelines to detect the location and size of distinct failures. Therefore, pipeline’s owner inserts the ILI or smart pigs and wait until it arrives to its destination (a control station) and then they analyze its data. The size of gathered data is considered as a big data which requires amount of time to study the status of the pipeline. However, these proposed architectures will help in reducing the time of detecting the pipeline’s defects such as cracks, corrosions, welds, and pipeline’s wall thickness by improving data transfer from the pipeline to the processor to extract useful information and deliver it to the onshore main station. Hence, decreasing delays in default detection.