The city of Miami in Florida faces growing flood risks due to rising sea levels, more frequent storms, and a low-lying coast. While hurricanes are often the triggers of major floods, tides also play an important role for minor flooding events, although these are often overlooked. This study investigates how changes in the layout of Biscayne Bay over the past century may have increased the tidal range and, consequently, the risk of high-tide floods. Using a simplified model, we compared the bay's historical and current layouts, the latter being deeply altered by the construction of the Miami harbor. Results show that the tidal range has significantly increased in the modern bay, largely because the natural dampening effect on tides has been reduced. The study also found that the size of the bay’s inlets has the biggest impact on tidal changes, highlighting how human activities can greatly affect the bay’s hydrodynamics.