Designing Rainwater Harvesting Systems for Large-Scale Potable Water Saving Using Spatial Information System

摘要

Rainwater harvesting systems (RWHSs) are promoted by many governments to enhance the availability of water resources and reduce the consumption of potable water. However, the traditional evaluation of RWHSs neglects the spatial-temporal complexity of rainfall and therefore can not be applied for a large-scale design. This study established a water saving information system (WSIS) incorporating hydraulic simulation, spatial interpolation, economic analysis and options selection, and use Taipei City as a case study. Two RWHS designs and low-flow toilets were tested through WSIS to visualize the spatial variance of the economic feasibility and to seek the optimum water-saving design. Sensitivity analysis also verifies that WSIS renders higher information value than the traditional generalized method. Hence, as a practical tool, this WSIS is useful for large-scale potable water-saving design to ease the water shortage problems.