Autodesk provides an number of different ways to calculate Stormwater Storage for detention ponds. Some may not be fully aware of the different methods or tools, so let’s review a couple of those options.
In AutoCAD Civil 3d, this Stage-Storage tool in the past few releases were external tools that found refuge in the toolbox. In 2011, those tools were brought to the ribbon. The other tool is the HEC-RAS Import / Export tool. (That’s another topic for another day…)
You can find the Stage-Storage Tools on the Analyze Ribbon, hidden away in the flyout of the Design Panel.
This launches the Stage Storage dialog box. This allows you to either calculate manually entered data, or auto-extract surface contours or polylines with elevation data.
This can be exported to an external text report, a saved table or an AutoCAD table within the product.
NOTE: Multiple areas are extracted, but the values are not calculated as one might expect. This presents different volume values that will be different that what you might expect. Use the extracted elevation/area data to build your Stage-Storage table in something like Hydraflow Hydrographs Pond builder or Excel.
This provides a nice workable solution to entering Storage areas in SSA.