Underwater Wireless Sensor Network (UWSN) has different benefit to human's life, such as aquatic exploration, commercial exploitation, environmental monitoring, coastline protection and disaster prevention. UWSN for environmental monitoring purpose has different characteristic from the common WSN. The environmental monitoring scenario with real-time and continuous sensing is a highly precise implementation of UWSN. This scenario has some characteristics and highly related with routing protocol of UWSN. To effectively implement the scenario, suitable routing protocol must be chosen. In this research, we analyse the simulation result in NS-3 with AquaSim framework by comparing the Vector Based Forwarding (VBF) and Depth Based Routing (DBR) routing mechanism. We compare the energy consumptions and packet delivery ratio with varying the number of nodes and the range of coverage area. We conclude that DBR has 33, 6% better energy efficient than VBF. It also has 19, 8% better packet delivery ratio. With that advantages, DBR will perform better than VBF in environmental monitoring implementations.