The Hydrologic Catalog
The US Geological Service has cataloged the streams and rivers across the nation in a hierarchial scheme using numerical codes. Twenty-one water resource regions have been designated and Pennsylvania has watersheds in three of these regions: the Mid-Atlantic (Region 02), the Ohio (Region 05), and the Great Lakes (Region 04). Bedford County is largely contained within the Mid-Atlantic Region but, along the western border, some of the county does drain into the Conemaugh River within the Ohio Region.
Regions are separated into subregions with 4-digit codes. The Susquehanna (0205) and the Potomac (0207) are the two subregions of interest for Bedford County. Subregions can include accounting units of 6-digits, the Susquehanna subregion has several with the Lower Susquehanna Accounting Unit (020503) of interest in Bedford County. Cataloging Units are the 8-digit codes that may be most familiar and are illustrated on the map. Most of Bedford County lies within the Raystown Cataloging Unit but the southern third, draining to the Potomac River, lies within either the North Potomac or Cacapon-Town Cataloging Units. Small parts of the northern and northeastern portions of the county drain to the Upper Juniata (02050302), by way of the Frankstown Branch, or the Lower Juniata (02050304).
Further divisions are designated watersheds of 10-digits, subwatersheds of 12-digits, and 14-digit reaches. An example of reach code designations is seen in the map of the Wallacks Branch area of the Bobs Creek watershed.
HUC codes can be important for watershed groups, other non-profits and state and local government agencies applying for grants and other funding as these codes are used as unambiguous means for identifying and locating a project site.

