Systems and methods for sensing water device run time, transmitting this data via a network to a database which analyzes, records and reports the individual run times and the aggregate use over any given timeframe. Sensors used to measure device use time do not directly measure flow rate, and may sense device run time by sensing water flow, through electronic signals, vibration, etc. The sensors may be battery powered and transmit discrete data packets via radio frequency to powered node units. A system of node units communicates with a central internet gateway which uploads the data packets to a cloud-based database which organizes, analyzes, stores and reports the information. The system allocates the cost of water flowing through a common water meter to a plurality of individual units within a collection of geographically proximate units. The systems are useful in multi-unit buildings or complexes having stacked plumbing.