Energy efficiency is the main challenge in wireless sensor network. Many routing protocols have been designed to face this challenge. Hierarchical cluster-based routing is one of the efficient techniques to route the sensed data from source node to sink node. The proposed algorithm deals with cluster formation based on different events, cluster head selection, aggregation of the sensed data within a cluster and sending that to the base station. Simulation result proves that the performance of the proposed scheme is better than Energy Efficient Clustering Algorithm for data aggregation in WSNs (EECA) and A Multipath Routing Protocol Based on Clustering and Ant Colony Optimization (MRP) for Wireless Sensor Networks. General Terms Energy Efficient Routing, Event driven cluster formation, Cluster Head selection