Laserfiche WebLink
Rainwater Harvesting Legal Framework <br />Page 7 <br />Chart 1. Stream Impacts of Native Condition compared to Rainwater Harvesting <br />For rainwater harvesting, an SWSP application must show how historic natural depletion (ET F. <br />soil moisture storage in the Native Condition in Chart 1) will be estimated, either using <br />Factors or a site-specific analysis. If Factors are not used, the amount of water that must be <br />replaced to the stream system is based on a direct measurement of the amount of rainwater <br />captured by the rainwater harvesting system. The timing of the replacement depends on if <br />that capture results in an instantaneous or tagged depletion (or both). <br />If Factors are not used, findings of historic natural depletion could potentially be based on <br />the following observation and analysis procedures: <br />Observation <br />Analysis <br />Precipitation <br />Observed precipitation data <br />Since the full range of possible storm frequencies <br />collected from an on-site rain gage <br />and durations will not occur during the two year <br />(during at least the two year <br />observation period, the observed precipitation data <br />observation period). <br />should be supplemented with data from a longer <br />period of nearby recorded precipitation data and/or <br />synthetic design storm data. <br />Distribution of Precipitation into Runoff Et Infiltration <br />