This success story showcases how 3D printing was integral to the uninterrupted operation of a city's water treatment plant. The plant faced an urgent issue when a critical plumbing component failed, putting its operations at risk. To prevent downtime, we swiftly designed and 3D printed a temporary replacement part using PETG, a material known for its resistance to both polymers and water. Additionally, we 3D printed custom gasket seals to exact specifications, ensuring a perfect fit and reliable performance. This allowed the plant to continue running smoothly while we manufactured the final, permanent replacement part from stainless steel. The speed and precision of 3D printing played a key role in keeping essential services operational without delay.