Rainwater Harvesting Performance in a Changing Climate

Rainwater harvesting (RWH) has gained increased attention in recent years as a sustainable technology capable of being a supplemental water source. Regional regression models can be used to generalize the storage yield relationship over a geographic area at a specified reliability by using certain statistics of daily rainfall as regression parameters. Such a regression is also potentially capable of analyzing changes in the storage-yield relationship due to changes in climate, so long as the changes in climate were reflected in the rainfall parameters selected for the regression. Several climate modelers have used general circulation models (GCM) to analyze potential changes to rainfall patterns many years in the future. Commonly, the gamma distribution parameters (α and β) fitted to rainfall amounts are used to investigate these changes. This study outlines a method for using these parameter projections in regional regression models to make conclusions about how rainwater harvesting will change in the future.