Current NHD & WBD Projects


Update the Stream Classifications in Coeur D’Alene Lake Area (Hydrologic Unit 17010303)



The NHD uses the FCODE attribute to classify River/Stream NHD Flowlines as perennial, intermittent or ephemeral. When the NHD was developed, cartographers classified streams either as perennial or intermittent based on available aerial photography at the time the map was compiled. Where available, these data were verified by field checks. However, some areas are not classified or classified incorrectly based on current field data.


The Idaho Department of Water Resources (IDWR) explored updating stream classification on Subbasin 17010303. This Subbasin was selected as a pilot area since all streams in this HU are classified as perennial even though many are intermittent. Al Rea and Kenneth Skinner of the USGS have developed a synthetic perennial stream dataset (Data Series 412). External link IDWR used the dataset developed by Rea & Skinner to update the stream classification in the NHD within HU 17010303. Field verification and traditional topographic classification was used to verify the stream classification.



This project has been funded by the United States Geological Survey and the Idaho Department of Water Resources.