A method and apparatus for controlling a Network Load Balancing (NLB) algorithm that balances a traffic load between multiple downlink (DL) sectors in a cellular telecommunication network. A Connection Integrity Preservation (CIP) algorithm, which runs on top of the NLB algorithm in the Radio Network Controller/Base Station Controller (RNC/BSC), minimizes the risk of degrading network performance due to NLB offload decisions. The CIP algorithm may override an NLB offload decision, for example, if there have been too many offload failures, there are no target DL sectors available to acquire an offloaded Access Terminal (AT), or the offloaded AT is not acquired within a threshold time period. The CIP algorithm ensures required metrics are collected, and minimizes the impact on RNC/BSC processing due to Routing Update messages needed to make offload decisions. The invention enables the NLB algorithm to realize its potential without negative side-effects.