Wildfires increasingly threaten drinking water supplies by degrading watershed health and reservoir water quality through elevated sediment, nutrient loading, and harmful algal blooms. Our project aims to improve monitoring and forecasting of post-fire hydrological impacts on watersheds and critical reservoirs through our new WaterScars Watch (https://wsw.mtri.org/home), an online decision-support tool that integrates satellite observations, remote sensing algorithms, and hydrological models. The system will monitor selected watersheds by combining active fire detections with burn scar mapping and automatically notify water managers when watersheds of interest are affected. WaterScars Watch leverages NASA-developed remote sensing capabilities to map post-fire sediment plumes and monitor vegetation recovery, providing insights into watershed recovery and erosion risk. Existing algorithms developed for detecting harmful algal blooms in the Great Lakes have been adapted for smaller reservoirs, expanding monitoring capabilities for drinking water resources. Throughout development, we are seeking water utilities, resource managers, and other stakeholders to identify user requirements and guide the design of the tool's interface and products. By integrating Earth observations with hydrological expertise, WaterScars Watch will provide an operational forecasting and monitoring capability to support post-fire decision-making, protect drinking water supplies, and improve watershed resilience.