Stage-Storage Relationships (Depth-Volume-Area) Using Lookup Tables

Stage-storage-volume/area are geometric relationships between water depth vs. storage volume and water depth vs. surface area in a pond or reservoir. Simple geometric formulas may be used to calculate the pond storage area and volume as a function of water depth.  This example discusses two methods for translating these relationships into a GoldSim model.

Method 1: One Lookup table and lookup table function (TBL_Integral)

One lookup table defined with depth vs area data is used in conjunction with the built-in lookup table function TBL_Integral is used to calculate volume. This method calculates volume based on the depth vs. area relationship. Thus, creating a depth vs. area vs. volume relationship. Note, the first volume entry in the elevation-volume lookup table is required to be 0, as shown in Elev_Volume_Table. This method calculates volume based on the depth vs. area relationship.

Method 2: Two lookup tables (depth vs area and depth vs volume)

Two lookup tables are defined with a geometric between elevation-area and elevation-volume to one lookup table. This method requires you to manually maintain any changes made to either lookup table.

Below is a model that demonstrates these two methods.