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# Pond Outflow

Pond outflow is calculated as a function of target storage. The target storage varies based on flood season and soil water content. The target pond volume is calculated:

&#x20;            $$V\_{targ}=V\_{em}$$        if    $$mon\_{fld,beg}\<mon\<mon\_{fld,end}$$                  8:1.2.11

&#x20;             $$V\_{targ}=V\_{pr}+\frac{(1-min\[\frac{SW}{FC},1])}{2}\*(V\_{em}-V\_{pr})$$

&#x20;                                          if ​ $$mon \le mon\_{fld,beg}$$ or   $$mon \ge mon\_{fld,end}$$    8:1.2.12

where $$V\_{targ}$$ is the target pond volume for a given day (m$$^3$$ H$$*2$$O), $$V*{em}$$ is the volume of water held in the pond when filled to the emergency spillway (m$$^3$$ H$$*2$$O), $$V*{pr}$$ is the volume of water held in the pond when filled to the principal spillway (m$$^3$$ H$$\_2$$O), $$SW$$ is the average soil water content in the subbasin (mm H$$*2$$O), $$FC$$ is the water content of the subbasin soil at field capacity (mm H$$*2$$O), $$mon$$ is the month of the year, $$mon*{fld,beg}$$ is the beginning month of the flood season, and $$mon*{fld,end}$$ is the ending month of the flood season.

&#x20;           Once the target storage is defined, the outflow is calculated:

&#x20;                $$V\_{flowout}=\frac{V-V\_{targ}}{ND\_{targ}}$$                                                                            8:1.2.13

&#x20;  where $$V\_{flowout}$$ is the volume of water flowing out of the water body during the day (m$$^3$$ H$$\_2$$O), $$V$$ is the volume of water stored in the pond (m$$^3$$ H$$*2$$O), $$V*{targ}$$ is the target pond volume for a given day (m$$^3$$ H$$*2$$O), and $$ND*{targ}$$ is the number of days required for the pond to reach target storage.