An intelligent water-monitoring system includes a water-monitoring device installable inline with a building water system (e.g., at an inlet of the system). A plurality of sensors of the water-monitoring device are configured to sense properties of the building water system, such as water pressure and water flow. The water-monitoring device has a valve and a controller configured to automatically shut the valve in response to sensed data indicating a possible problem in the building water system. The intelligent water-monitoring system may include an app executable by a computing device to display information based on the sensed data.