The developments of micro and nano sensors lead the sensor networking technology to be used in all kinds of study. In underwater communications and study, wireless sensor network plays a major role. One among the characteristics of underwater communications is propagation delay that affects the network throughput. To increase the throughput, here we propose the local update routing. In this technique the end to end delay is minimized by using hierarchical WPANs. This is proved with reduced latency using Omnet++ simulator.