165. StorageToArea

This function performs a lookup in a Reservoir object's Elevation Volume Table based on a given storage to determine the corresponding pool elevation. The function then uses this pool elevation for a lookup in the Reservoir's Elevation Area Table and evaluates to the corresponding area.

Description

Find the area of a given reservoir with a given storage.

Type

NUMERIC

Arguments

Type

Meaning

1

OBJECT

reservoir object

2

NUMERIC

storage

Evaluation

The storage argument is looked up in the Storage column of the Elevation Volume Table of the reservoir object argument to determine the Pool Elevation. If the exact storage is not in the table, the lookup performs a linear interpolation between the two nearest bounding storages and their corresponding pool elevations. The pool elevation is then looked up in the Pool Elevation column of the Elevation Area Table to determine the Surface Area. If the exact elevation is not in the table, another linear interpolation is performed. The function evaluates to the computed surface area.

Mathematical Expression
StorageToArea.jpg
StorageToArea2.jpg

Comments

If the object is not a reservoir or the reservoir does not have an Elevation Area Table, the function aborts the run with an error (CRSSEvaporationCalc, DailyEvaporationCalc, PanAndIceEvaporation, heatBudgetEvaporation, or InputEvaporation must be selected as the Evaporation and Precipitation Category selected Method).

If the reservoir is a Slope Power Reservoir, the calculation is based only on level storage and does not include any wedge storage effects.

This function will issue an error if the "Time Varying Elevation Volume" method, (Objects.pdf, Section 22.1.23.3) , or "Time Varying Elevation Area" method, (Objects.pdf, Section 22.1.24.2) ,is selected. Instead, use the StorageToAreaAtDate function described next.

Syntax Example:

StorageToArea(%"WattsBar", 442.39 "1000 cfsday")

Return Example:

12203.231 "m2"