Dams have been built in the developing world over the past many decades. Recent data suggest that more dams can be expected in the near future with many already under construction. Due to lack of in-situ data or data sharing protocols among developing nations, the exploration of  the role of dams in altering rivers in developing regions has been challenging. Today, using a plethora of multi-sensor earth observations from space, we can now build a more complete and multi-decadal record of the state of dams such as reservoir storage change, outflow, and thermal impacts. This talk will address how dams are changing our rivers in developing regions of the world. Using big data, cloud computing and distributed modeling, the talk will try to show that we now have the tools to pursue a more comprehensive management of water resources in international river basins for better policy, planning, and transboundary cooperation.