Long-reach optical access technologies have emerged as a promising solution for combining access and metro backhaul networks in a cost-effective manner. This study develops a Slotted PON (SPON) architecture based upon an AWG for long-reach optical access networks. The AWG enables the SPON to achieve wavelength spatial-reuse and to provide an internetworking capability amongst ONUs located within different local access networks. In addition, a Slotted MAC (SMAC) protocol is proposed to arbitrate the access of the individual ONUs over the DWDM layer. The simulation results show that the SPON architecture integrated with SMAC protocol enhances the bandwidth utilization within the network, and therefore achieve a significant reduction in the average packet delay.