Tag Archives: HEM
by Ariel T. Doumbouya, NHD Team, United States Geological Survey
Fish sampling sites in the Nashua River Subbasin in Massachusetts are linked to the National Hydrography Dataset (NHD) as events using the Hydrography Event Management (HEM) Tools. Events allow scientific information to be linked to the NHD which provides a powerful modeling framework that can be used to locate water related information on the network, establish up and/or downstream relationships, perform habitat and species modeling, and determine relationships between other environmental factors.
by Kathy Isham, National Hydrography Dataset, USGS The US Geological Survey (USGS) has redesigned its applications page for the National Hydrography Dataset (NHD). The new applications page is organized into the six different types of applications that highlight how USGS … Continue reading
A new release of the Hydrography Event Management (HEM) Tool is available for ArcGIS 10. The HEM Tool provides full functionality for adding and editing events in the National Hydrography Dataset (NHD). Events are informational data that are linked to the NHD using a linear referencing on NHDFlowlines. The HEM tool handles all the linear referencing mechanics to make working with events simple. Hydrography events support many applications such as resource management, environmental protection, emergency response, fisheries and much more.
Enhancements to Version 2.5 include:
- Added a Pan button to candidate form.
- Candidate form can list an additional attribute per event layer. Values from each event layer’s ‘Display Expression’ field will be listed in the candidate form.
- Import to Events – before starting batch import the tool will now verify the spatial reference of the data frame and the NHDFlowline feature class are exactly the same.
- Import to Events will warn the user if they are about to apply approved imported events to a base table with the same name. Users have the option to stop or continue the process.
- Import to Events can now transfer no fields, just the link field, or all fields. All fields only works for standard field types (string, date, and numeric). Blobs, OIDs, GUIDs and shape type fields will not transfer.
- Create Multiple Events Downstream – Added new functionality (button) to create multiple downstream events from a point layer in the map. Not default on HEM toolbar, found under Customize > Commands > Categories > HEM > Batch Downstream from Points. Option to create overlapping or non-overlapping events from input points.
- Import to Events QC and Batch Sync QC will now allow users to select multiple rows at once and approve them all.
- SourceFeatureID now has an option to enforce unique IDs in event feature classes.
Find out more information and download the tool at: http://nhd.usgs.gov/tools.html.
An online demo of new features will be scheduled for the week of Oct 31st, email firstname.lastname@example.org to attend.
Special thanks to Ariel Doumbouya for providing this post. Questions for Ariel: email@example.com.
The Hydrography Event Management (HEM) Tool Version 2.4 for ArcGIS 10 is now available!
The HEM Tool provides full functionality for adding and editing events in the National Hydrography Dataset (NHD).
Events are informational data linked to the NHD using a linear
referencing system on NHDFlowlines. The use of events allows vast
amounts of scientific information to be linked to the NHD.
The HEM tool handles all linear referencing mechanics to make working with events easy. It works on point, line, and area events and allows events to be located interactively, imported, or calculated.
A number of state and federal partners have adopted HEM: Environmental Protection Agency (EPA) incorporated HEM to meet Clean Water Act reporting requirements, the U.S. Forest Service incorporated HEM functionality into their National Resource Information System (NRIS) Aquatic Surveys application, Bureau of Land Management (BLM) incorporated HEM to support event creation for its Oregon/Washington Aquatic Resource Information Management System
and is evaluating its use for a national Riparian Database, and the HEM
Tool is used to georeference water quality data to the NHD, and this
information is then used for Section 303(d) water quality reports on impaired waters.
HEM effort is a unique collaboration between the BLM, U.S. Geological
Survey (USGS), and the EPA that results in ongoing tool development and
support to the expanding HEM user community.
The USGS provides basic to advanced HEM training with easy to follow exercises:
and additional user support in the Troubleshooting Guide.
To find out more information visit USGS’s HEM site.
Special thanks to Ariel Bates for providing the post. Questions for Ariel: firstname.lastname@example.org