https://github.com/geostreams/gltg/issues/16

2012 Nutrient Model results by SPARROW

https://www.sciencebase.gov/catalog/item/5cbf5150e4b09b8c0b700df3

Need to aggregate to HUC8

The data (total N and P) is organized by ComID.

Therefore, we need to add up the value of comID to the HUC8 that comIDs are belong to. 

Data

• total N and P text file (ID: comid)
• catchment to huc12 crosswalk data: (https://www.epa.gov/waterdata/nhdplus-national-data)
  • DBF file
• HUC8 boundary shapefile

Steps

• Derive a relationship table between (catchment (COMID) and HUC8) from crosswalk data above
• calculate (add up) the total N and P value by huc8 by using table above
• join the table above (calcualted table) with HUC8 boundary

2002 Nutrient Model Results by SPARROW

Nitrogen output

Phosphorus

 We need to join the table with HUC8 boundary to generate geospatial layer