The Government of Nunavut Department of Community and Government Services (CGS), on behalf of the Hamlet of Naujaat, is applying for the construction of a single cell lagoon located adjacent the current wastewater disposal site, and amendment of the discharge effluent limits in the existing water licence to effectively service the growing population in Naujaat until the design horizon of 2043. The treatment facility will be designed with a new upstream primary lagoon cell that is impermeable. The existing downstream natural depression that is acting as the current lagoon will become a secondary treatment cell, and the existing downstream wetland-treatment-area (WTA) will remain in use. Seasonal effluent pump out to the secondary cell and WTA is to occur late in the summer season to allow spring freshet to pass and to allow the wetland to recharge to promote its ability to support effluent biodegradation. The requested amendment to the effluent limits within the WTA is based on the most comprehensive research completed to date on lagoon-wetland systems in Nunavut, and considers the significant change to the hydrologic regime that will be influenced by the seasonal pump out of the future impermeable lagoon that will replace the passive exfiltration and dilution that occurs now. CGS retained Dillon Consulting Limited to develop the Pre-Design Report for the upgrade of the current sewage facility in the Hamlet of Naujaat. This study projected the flow and loadings based on the population growth, proposed the treated effluent goals and standards, reviewed and selected the most suitable location and treatment technologies, sized the lagoon system, and developed a conceptual schematic design. The treatment goals for the lagoon-wetland effluent criteria, at the end of the treatment process, were established as 100, 120, and 1.25 mg/L for carbonaceous biochemical oxygen demand, total suspended solids, and un-ionized ammonia as nitrogen, respectively, to protect the final receiving environment. These effluent criteria are based on 6 years of research completed by the Centre for Water Resources Studies at Dalhousie University directly in Naujaat and across Nunavut. Given an estimated population of 1,225 residents in 2021 by Statistics Canada, the design population to be serviced by the expanded lagoon was projected to be 2,175 people in 2043. This population will require an active storage volume 121,469 m3 for 12 months of storage. The lagoon discharge point will be by controlled manual pump out into the secondary lagoon that will then exfiltrate into the WTA which will remain at the same location. The decant system will be designed with a flowrate below 2500 m3/day to ensure effluent has sufficient residency time in the WTA.