The USGS Streamflow Importer is launched from the Tools | Data | Gage | USGS Import menu in HEC-HMS.

A project must be open to access the USGS Streamflow Importer.

Step 1: Query Sites

The USGS site query requires arguments for parameter, spatial bounds, time bounds, and data interval.

Select the parameter. Currently flow and stage are supported.

Set the spatial bounds by specifying degrees north, south, east, and west. To set spatial bounds from a two-dimensionally spatial basin model, click the basin button to select a basin model. To set spatial bounds from a shapefile, click the folder button to launch a shapefile file chooser.

Set the time bounds by specifying start date, start time, end dates and end time. Dates must be formatted as d-MMM-YYYY. Times must be formatted as HH:mm.

Select the time interval for the data. The USGS provides two options: instantaneous and daily.

After parameterizing the query, click Query to query the web service.

After a successful query, results will display in the sites table.

In the Import column of the sites table, sites can be selected/deselected for import. All sites can be selected/deselected with the checkbox in the table header.

After site selections are made, click Import to proceed to the import options dialog.

Step 2: Query Data and Import

The Import Options dialog provides options for import to HEC-DSS and the HEC-HMS project. Descriptions for columns in the dialog follow:

Site ID: The USGS site number.

Part A: The HEC-DSS A Part for the HEC-DSS record to be written.

Part B: The HEC-DSS B Part for the HEC-DSS record to be written. Default: the USGS site location.

Part C: The HEC-DSS C Part for the HEC-DSS record to be written. Default: the HEC-HMS C Part convention for flow or stage. This field cannot be edited.

Part F: The HEC-DSS F Part for the HEC-DSS record to be written. Default: the data source, "USGS".

Time Zone: The time zone for the data. Options include local standard time for the gage, local daylight time for the gage (if present), and universal coordinated time (UTC). Default: universal coordinated time (UTC).

Time Series Gage: The time series gage shared data component in HEC-HMS. An existing or non-existing gage can be specified. If a non-existing gage is specified, it will be created. Default: "USGS <site number> <Inst or Daily>" to uniquely identify the time series gage within character limits. If no description is set for the gage, it will be set to the USGS site location, e.g. "Mahoning Creek at Punxsutawney, PA".

HEC-DSS File: The HEC-DSS file to be written. If the time-series gage exists, the HEC-DSS file specification assumes the existing file specification for the time-series gage and cannot be edited. If the time-series gage does not exist, the HEC-DSS file specification is editable. Default "<project dir>/data/observed.dss".

After specifying these fields for each gage, click Import to query and import data.

Overwrite

For HEC-DSS files and records that already exist, data will be overwritten without warning!

Click close to Close the Import Progress dialog and return to the USGS Time Series Importer query dialog.

After a successful import, new time-series gages will be present on the flow or stage time-series gage nodes in the HEC-HMS Watershed Explorer.