Last modified 4 years ago Last modified on 10/07/14 06:04:19

Upper Neuse Demo

Overall goal:

Create a table of NHD+ catchments listing summary statistics and species observations (or IBI ratings) that can be used to quantify (statistcally) the sensitivity of the species (or IBI scores) to management activities.


  • Organize flow line related attributes
    • Length
    • Slope
    • Flow volume
    • Flow velocity
    • Stream order
    • Arbolate length
  • Organize drainage characteristics
    • Marginal drainage area
    • Total upslope area


Prep Data

NHD feature and raster Data

  • Select NHDplus flow lines matching HUC6 = 0302020 and Project to Albers EQ Area Conic --> NHDFlowlines
  • Select and project WBDHU6 matching 0302020 --> WBDHU6
  • Select and project WBDSnapshot (WDB12) --> WBD_subwatershed
  • Select and project NHD catchment features having their center in WBDHU6 features --> NHDCatchments
  • Dissolve NHDCatchments into a single feature --> MaskPoly
  • Convert MaskPoly? into a raster, using NHD catchments as cell size and snap raster --> mask
  • Extract catchments using mask --> catchments
  • Extract fdr using mask --> fdr
  • Extract fdr_null using mask --> fdr_null

NHD tabular data

  • Copy NHDFlowline attribute table to GDB --> FlowlineData
  • Join fields from PlusFlowlineVAA: StreamOrde, PathLength, ArbolateSu, AreaSqKM
  • Join fields from CumulativeArea: TotDASqKM
  • Join fields from ElevSlope: SLOPE, SLOPELENKM
  • Join fields from EROM_MA0001: Q0001E,V001E, Qincr0001E, TEMP0001, PPT0001, PET0001, QLOSS001
  • Copy NHDFlowline attribute table to GDB --> FlowlineFlowData
    • Batch join monthly flow data EROMXX0001: Q0001E,V001E, Qincr0001E, TEMP0001, PPT0001, PET0001, QLOSS001
    • --> Calculate min, max, mean, std, of monthly values

Determine additional flow line attributes

  • --> Sinuosity

1. Calculate Flow Line statistics

  • Extract flowline from FDRnull (where values = NoData)
  • Extract NLCD for flowline cells
  • Tabulate Areas of NLCD classes in flow line cells for each catchment --> FlowLineNLCD

2a. Create Riparian zone datasets

  • Calculate downstream flow length using FDRnull dataset (flow distance to stream) --> FDist2Strm
  • Set distance values > 100 to NoData, otherwise to 1 --> RipMask
  • Set distance values > 100 to NoData, otherwise to catchments --> RipCatchment

2b. Calculate Riparian zone statistics

  • Tabulate area of NLCD for each catchment --> RiparianNLCD

3. Calculate catchment statistics

  • Tabulate area of NLCD classes within each catchment --> CatchmentNLCD
  • Tabulate total impervious area (Zonal Sum) within each catchment --> CatchmentImpervious
  • Tabulate total forest cover (Zonal Sum) within each catchment -->

Calculate upstream statistics

  • Convert NLCD classes to binary rasters: Developed, Barren, Forest, Scrub, Ag, Wetland
  • Calculated weighted flow accumulation using above binaries
  • Calculate zonal max of above accumulations by catchment