The maintenance of aging water infrastructure is one of the most significant challenges in modern civil engineering. Dams, spillways, and intake structures are subject to constant hydrostatic pressure, erosion, and thermal stresses that can lead to structural cracking. When these cracks are "fixed" through grouting or structural reinforcement, engineers must ensure the repair can withstand complex 3D flow patterns and pressure fluctuations. FLOW-3D HYDRO, an industry-leading CFD solution, provides the necessary precision to simulate these interactions, acting as a "virtual laboratory" to validate the success of these repairs.