*Step 13: Calculate practice drainage time, t<sub>p</sub> (h), which is the time required to fully drain d<sub>i</sub> or d<sub>i</sub>' assuming one dimensional drainage from the storage reservoir bottom: | *Step 13: Calculate practice drainage time, t<sub>p</sub> (h), which is the time required to fully drain d<sub>i</sub> or d<sub>i</sub>' assuming one dimensional drainage from the storage reservoir bottom: |