The U.S. Environmental Protection Agency (EPA) has developed a supplemental set of indexing functions for the Hydrography Event Management (HEM) Tool, which are available through the HEM EPA Add-On Toolbar.

This toolbar allows users to create, edit and manage custom point, line and area events. The toolbar also includes functionality that was previously a part of the PC-based Reach Indexing Tool (PC-RIT), such as Find Overlapping Waterbodies, Extract from EPA Program Events, and a post processing tool to aid in preparing events for submission to the EPA’s Reach Address Database (RAD). The HEM EPA Add-on Tools are currently available for use with ArcGIS Version 9.3.1., and a version of the HEM EPA Add-on Tools for use with ArcGIS 10 is in development.

Please note that The HEM tool along with the EPA Add-On Tools supersedes the ArcView 3.0 based Reach Indexing Tool (RIT).

The tools and training materials are available for download at http://nhd.usgs.gov/tools.html.

USGS currently has two 4-hour HEM WebEx training sessions scheduled for September.
Advanced Editing Part 2 - September 7
Data Maintenance Part 3 - September 28

Sign up at: http://nhd.usgs.gov/tools.html#hem