1. Large Scale Water Conservation System for Multi-Unit Housing H 2 Opti ns

2. Purpose of System Water consumption in many apartment buildings can not be traced to individual units Leaking water fixtures are hard to identify if not reported by residents Inspecting all units is required to find the few leaking fixtures Our system identifies problems so that timely repairs can be made before significant water is wasted

3. System Description Toilet and faucet sensors detect water flow Sensor readings are transmitted from each fixture to on-site base station Base station compiles sensor readings to provide information on leaking faucets Leaking faucet maintenance is coordinated based on review of base station data Costs are kept low with simple components and power conservation

4. Custom Flow Switch & Hall Effect Sensor

5. Custom Network Architecture Static, clustered network Modified TinyOS allows Coordinator motes to communicate on two groupids Coordinator motes form multi-hop network Sensor motes attach to closest Coordinator Coordinator mote assign TOS_LOCAL to Sensors

6. Data Reporting 2 Types –Data Compression Each sensor compresses its ons and offs using homegrown Arithmetic coding algorithm Base station uncompresses and looks for patterns –Quadrant Mapping Each sensor transmits total number of ons and total number of distinct water events Base station maps data on quadrant chart Fixtures mapped into the High Number of Ons/Low Number of Water Events quadrant are investigated

7. Next Steps Beta test at a current client-site Standardize packaging and installation Roll out as a viable water conservation tool