I need the shapefiles of all river basins polygons of USA. I need these boundaries:
in order to create river basins map in combination with DEM data.
Those are the HU-2 (2-digit Hydrologic Units) boundaries from the national Watershed Boundary Dataset (WBD). Sometimes you'll see them referred to as HUC-2 instead of HU-2 (HUC = Hydrologic Unit Code).
It should be possible to download this data for the entire continental US as a single dataset. However...
It's more difficult to get the actual data. According to the metadata page, you can download the WBD data through the National Map viewer. But as far as I could tell, the national WBD dataset is not actually available through the map viewer right now. I went through the steps to download the national WBD dataset, but nothing was listed on the "data products" page.
The 2-digit Hydrologic Unit boundaries are available separately for each watershed. For example, the Missouri watershed boundary is one single download called WBD_10_HU2_Shape.zip. This file contains:
Here are direct links to all the 2-digit Hydrologic Units in the United States, in shapefile format. You can re-create the national WBD layer by stitching together the WBDHU2 layer from each zip file. Looking at the image you posted, you may want to include some smaller subwatersheds along the east coast, Gulf coast and in the Rocky Mountains. I don't see any obvious pattern to which watersheds are color-coded separately, so you'll probably have to manually select the ones you want from the different HUC levels. Pro tip: the larger the HUC number, the smaller the watershed, ie HUC-2 watersheds are the largest, and HUC-16 are the smallest.
These are the download links that I got by going through the National Map Viewer. I hope they work for you, but I'm not sure if they're temporary/personal links or permalinks. If they don't work, you'll have to go through the National Map Viewer yourself. Follow the steps illustrated below to find these layers in the National Map Viewer interface.
You can also see the various HU layers on ArcGIS.com, including previewing them on a map and linking to them as a MapService.
Note: If anyone wants to edit this question and put the HU-2 layers in numerical order, and/or look up and add the watershed names, that would be great.
UPDATE: I found a direct download source for Watershed Boundary Dataset and Lines for HUC2-12. They're subdivided by HUC-level (HU2, HU4, HU6, etc.) Each file contains the Hydrologic Unit boundaries for the entire nation; you can also download HUC2-12 as one zip file. Thank you USDA National Resources Conservation Service, you really one-upped the USGS this time.