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Rainwater Harvesting Legal Framework Page 6 2. Describe each diversion (for storage of rainwater) and if that results in instantaneous or lagged depletion (or both). Descriptions of depletions should list stream impacts in terms of location, timing and amount; 3. Describe if the rainwater harvesting system could potentially store an amount of water in excess of the historical natural depletion, and if such excess storage occurs, will the water be released or augmented, and 4. Describe each replacement water source by timing, location, and amount. Each item in the application may be supported by several detailed calculations. Also, the Application must be supported by a summary table showing monthly diversions, lagged depletions, monthly replacements (including transit loss if applicable), and net impact to the river. The net impact to the river must result in replacement either equal to or greater than depletions. Maps of all facilities included are also required. The existing SWSP guidance was written prior to rainwater harvesting legislation and does not consider the unique method of causing depletions through rainwater harvesting. For pilot projects that are not using Factors, for the first two years 100 percent of captured precipitation is considered a depletion. After the two year data collection phase (without Factors), the historic natural depletion need not be replaced. When Factors are used, the two year data collection period with full replacement is not required. Chart 1 is an example of how precipitation is divided into ET, soil moisture storage, surface and groundwater return flows. ET Et soil moisture storage is equal to historic natural depletion. The total to the stream is the sum of runoff, deep percolation, and augmentation. Under a pilot project with rainwater harvesting (case B), if some of the reused precipitation is in excess of that amount attributable to the historical natural depletion, the excess amount is an out -of -priority depletion requiring a delivery of augmentation water to the stream. This example also shows that a project operating under an SWSP for the first two years without using the factors (case C), and needing to augment all of the harvested precipitation, results in more water accruing to the stream than historical conditions.