California relies on federal satellites to understand and manage its water resources every day. Data from these satellites are used to estimate irrigation use, manage groundwater, predict storms, assess flooding, and track water quality, among many other applications. … What may not be as well known is that Landsat—along with other federal satellites—also plays a key role in California water management. While it would take too much time to catalogue all the ways California uses federal satellite data to manage our water resources, a few examples illustrate the importance of these data.