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This project concerns the computations required to determine the drawdown for the retention/detention of ponds. Drawdown refers to the volume of water in a pond that decreases as the water flows out. The falling head equation has many applications and can be used to calculate the drawdown of a pond through various shaped openings. In particular, we analyze four outflow structures: a rectangular-notch weir, a v-notch weir, a round orifice, and an underdrain. For each instance, we modify the falling head equation to reflect the shape of the respective orifice.


This article was previously called Article 27.

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Arcadii Grinshpan, Mathematics and Statistics

Scott Hickerson, Southwest Florida Water Management District: Civil Engineer

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Scott Hickerson