Return to Task 4. Fit Marginal Distributions in HEC-SSP.

Create an HEC-Neptune Project

  • Open HEC-Neptune v alpha.
  • In the lower right corner, select Preferences.
  • You can set set project preferences such as color scheme, UI size, density, display precision, and default project location.
  • Click Save once you've set your preferences.
  • Click Create New Project. 
  • Enter Philippi Interior Drainage as the Project Name. 
  • The Directory will automatically populate with your default project location. 
  • Leave the Default Unit System set to U.S. Customary.
  • Select Create Project.

Import Data

  • From the top ribbon, select Data | New Data | Import from CSV.
  • In the CSV Importer, make sure the Structure Type is set to Time Series.
  • Drag the flow_dominant.csv file into the Source field.
  • Leave the Name as flow_dominant and enter Annual peak 1-day flow and near coincident 3-day precip in the Description field.
  • The Structure tab should appear as in the image below.
  • Click the Next button.
  • Under the Column mapping, change the Role of rows 1, 4, and 6 to Ignore since we don't want to import these rows.
  • Make sure that the Role of row 2 (flow_date) is set to Date/Time and the Role of rows 3 and 5 (flow and precipitation) is set to Value.
  • Change the Output name for rows 2, 3, and 5 to Date, Flow_AMS, and Precipitation_Coincident, respectively.
  • For the flow row, make the following selections:
    • Parameter: Flow
    • Units: Cubic Feet Per Second (CFS)
    • Value Type: INST-VAL
  • For the precipitation row, make the following selections:
    • Parameter: Precipitation
    • Units: Incremental Inches
    • Value Type: PER-CUM
  • The Importer should appear as in image below.
  • You can click the Tabulate button to view the data that will be imported in tabular form.
  • Click Import Data.
  • In the Project Tree, expand the Data node. Notice that the project now contains a Discharge node and a Precipitation node. Expand both.
  • Notice that the dataset and value names were concatenated with a dash (e.g. flow_dominant - Precipitation_Coincident and flow_dominant - Flow_AMS).
  • To plot the two time series, hold the Ctrl key on your keyboard and left click on the time series. Right click and select Plot.
  • Select the Show Range Slider to zoom into a specific time period or view both time series in the same plot panel.


  • Repeat the previous steps to import the time series in the precipitation_dominant.csv file.
  • Enter Annual peak 3-day precipitation and near coincident 1-day flow in the Description field.
  • Select Ignore as the Role for rows 1, 4, and 6. Set the Role for row 2 to Date/Time and the Role for rows 3 and 5 to Value.
  • Use Date, Precipitation_AMS, and Flow_Coincident as the names for rows 2, 3, and 5, respectively.
  • Select the same parameter, units, and value type as before.
  • Your Project Tree should appear as in the image below.

Continue to Task 6. Define and Fit Copulas in HEC-Neptune.