Where the total contributing drainage area (A<sub>c</sub>) and total depth of clear stone aggregate needed for load bearing capacity are known (i.e., storage reservoir depth is fixed) or if available space is constrained in the vertical dimension due to water table or bedrock elevation, the minimum footprint area of the water storage reservoir, A<sub>r</sub> can be calculated as follows:<br>
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Where the total contributing drainage area (A<sub>c</sub>) and total depth of clear stone aggregate needed for load bearing capacity of the pavement are known (i.e., storage reservoir depth is fixed) or if available space is constrained in the vertical dimension due to water table or bedrock elevation, the minimum footprint area of the water storage reservoir, A<sub>r</sub> can be calculated as follows:<br>