These graphs were created with data collected this month. The first shows how each test roof compares to a theoretical “perfectly draining” roof from which 100% of rain that falls on it drains off immediately (labeled as Equivalent Box Volume). In the upper left corner a plot of rainfall intensity shows the rates of precipitation in inches per hour. In this event the commercial media stored the most water with a retention rate of approximately 80%. Native soil boxes danced around the 60% to 70% retention mark.
The second image shows plots of soil moisture over a week of dry days framed by a storm at the beginning and end of the data set. Relevant notes are on the graph.