The City of Athens, located in the Appalachian region of eastern Tennessee, has been defined by its relationship with Oostanaula Creek since its incorporation in 1822. Originally harnessed to power the mills that drove economy, Oostanaula now creates a looming flood risk for the City. Expansion in the region has led to decades of urbanization, increasing runoff and overwhelming existing stormwater infrastructure. The City of Athens is now at a cross-roads and in need of a plan to combat this ever-increasing problem. This presentation highlights the American Rescue Plan (ARP) Stormwater Masterplan in Athens, Tennessee as a comprehensive shift from historical reactivity to proactive, data driven resilience. The Masterplan is centered around a comprehensive 1D/2D hydrologic and hydraulic modeling approach, integrating HEC-HMS and HEC-RAS 2D to evaluate complex riverine systems and PCSWMM for closed system networks. This analysis gives a full picture of the existing stormwater dynamics throughout Athens and lays the framework for tackling the stormwater challenges plaguing the city. This Masterplan delivers a detailed evaluation of existing conditions and deficiencies and a Capital Improvement Plan that tailors solutions to priority locations. Three construction projects informed by the results of this modeling are currently underway, actively addressing improvements to riverine flooding, stormwater detention, and water quality. The City of Athens is a case study for how Tennessee communities can leverage federal recovery funds to solve diverse hydraulic challenges through comprehensive stormwater modeling. This presentation will review the project scope, achievements, and technical challenges, including: • Geographical and Historical Context: Overview of Athens’s geographical location, current stormwater challenges, and previous mitigation strategies for stormwater and water quality. • Smart Data Collection: Overcoming asset underestimation and funding by utilization of alternative data sources to build a robust GIS Geodatabase for long term asset management. • Integrated Hydrologic and Hydraulic Modeling: Utilization of the latest USACE HEC-HMS and HEC-RAS-2D software for primary system modeling and PCSWMM for secondary system modeling. • Problem Identification: Pinpointing flooding areas through primary and secondary system modeling and City feedback. • Solutions and Recommendations: Utilization of hydraulic models to evaluate conceptual solutions to the identified problem areas, differentiating between open system floodplain reconnection and closed system conveyance storage and capacity upgrades. • Funding and Implementation: Proposal of a stormwater utility to finance ongoing improvements of the City's stormwater management system.