Projects

The Multi-Scale Aquatic Assessment and Planning Framework is a fine-scale to broad-scale assessment using true watersheds as delineated in the "USGS National Hydrography Dataset". The Subbasin, a 4th HUC, is the broad-scale summary unit, and the Subwatersheds, a 6th HUC, is the fine-scale summary unit.

The Upper Salmon River Subbasin is used below as an example displaying how the watersheds are mapped and coded from the large Regional scale down to stream reaches that make up the fine scale at the 6th HUC level. The nested hierarchy of watersheds facilitates aggregation and disaggregation of data for the scale specific data summary displays in the multi-scale framework.

1. Region

Pacific Northwest Water Region (17)

-Located in: United States of America

~250,000 sq. miles

~647,497 sq. km

2. Sub-Region

Lower Snake River Basin: below Hells Canyon Dam to its confluence with the Columbia River.

-Located in: Pacific Northwest Water Region (17)

2nd field HUC

1706

~35,200 sq. miles

~91,168 sq. km

3. Basin or Accounting Unit (3rd code HUC)

Salmon River Basin

-Located in: Lower Snake River Basin

3rd field HUC

170602

~14,000 sq. miles

~36,260 sq. km

4. Sub-Basin or Cataloging Unit (4th code HUC)

Upper Salmon River Subbasin

-Located in: Salmon River Basin

4th field HUC

17060201

~2,410 sq. miles

~6,242 sq. km

5. Watershed (5th code HUC)

Upper Salmon River Subbasin (full view)

-Located in: Salmon River Basin

Shown here delineated into 5th field HUCs

17060201

~2,410 sq. miles

~6,242 sq. km

6. Sub-Watershed (6th code HUC)

Upper Salmon River Subbasin (full view)

-Located in: Salmon River Basin

Shown here delineated into 6th field HUCs

17060201

~2,410 sq. miles

~6,242 sq. km