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NHD Watershed: Tools and Applications

NHD Watershed: Tools and Applications. By Pete Steeves, USGS Water Resources Discipline Northboro, Massachusetts 508-490-5054 psteeves@usgs.gov. Acknowledgements. Jennifer Hill, Horizons Systems Corporation Aleda Freeman, MassGIS Craig Johnston, USGS. This Talk Focuses on:.

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NHD Watershed: Tools and Applications

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  1. NHD Watershed: Tools and Applications By Pete Steeves, USGS Water Resources Discipline Northboro, Massachusetts508-490-5054psteeves@usgs.gov

  2. Acknowledgements • Jennifer Hill, Horizons Systems Corporation • Aleda Freeman, MassGIS • Craig Johnston, USGS

  3. This Talk Focuses on: • 2 NHD ArcView Toolkit extensions • NHD Watershed • NHD Watershed Characteristics • 3 Applications of these extensions • VT Flood Frequency project • New Hampshire Low Flow project • Massachusetts Perennial / Intermittent streams project

  4. Background • Massachusetts Watershed Analyst (MassGIS and USGS collaboration) • Tools and datasets not immediately transferable nationally • An application, Massachusetts ‘Streamstats’ showcases the applicability of these tools • http://ma.water.usgs.gov/streamstats

  5. NHD Watershed: Objectives • To develop a tool in the NHD ArcView Toolkit which delineates a watershed from any point location on NHD reaches quickly, reliably, and accurately • To relate the resulting watershed to the reach and measure of the selected point (in essence, create a “polygon event”) • To horizontally integrate 3 earth-surface-based physiographic datasets (hydrography, basin boundaries, and elevation data) through a series of pre-processing steps • To document the pre-processing steps for others

  6. National Datalayers • Hi-resolution NHD (1:24,000 scale) • 12-digit hydrologic unit (HUC) boundaries (future WBD) (1:24,000 source scale) • National Elevation Dataset (NED)

  7. Pilot HUC:White River Basin, VT (01080105)

  8. Pre-processing steps - NHD • Convert the NHD route.rch table to an arc coverage and direct all flow downstream • Remove all routes that are not connected to major networks • Optionally remove sections of braids (resulting in a dendrite network) • Extend the exit centerline ~ 50 meters beyond the HUC boundary

  9. Example: Removing a Braid

  10. Pre-processing steps - WBD • Optionally add sub-basin boundaries to the 12-digit HUC datalayer. • Buffer the 8-digit HUC boundary 4000 meters for the subsequent TOPOGRID command analysis area • Buffer the 8-digit HUC boundary 50 meters to ensure the vector boundary will be used in all raster analysis steps

  11. Example: Adding Sub-basins

  12. Pre-processing steps - NED • Run TOPOGRID to drainage enforce the NED to NHD. Input includes: • The edited dendrite network from NHD • A NED-derived point coverage of elevation values • Use a series of GRID steps to exaggerate the watershed boundary ridges where TOPOGRID output coincides with the WBD • Run ‘agree.aml’ to ‘canyonize’ the dendrite using output from the TOPOGRID/ridge steps, further enforcing the NED to NHD

  13. Example: Enforcing NED to NHD

  14. Final Pre-processing Steps • Use the drainage enforced elevation grid to produce the flow direction and flow accumulation grids (then discard the drainage enforced elevation grid) • Use the ‘WATERSHED’ command to delineate a catchment for every NHD reach in the dendrite coverage • Load the appropriate datasets into a standardized ‘NHD Watershed’ directory

  15. Reaches Catchments

  16. NHD Watershed Directory Structure

  17. How NHD Watershed Works • The user selects a point on a reach • NHD Navigate determines all upstream reaches from that point (including the partial reach segment of the selected reach) • A relate is performed between reaches and catchments to select all upstream catchments • A partial catchment is determined within the selected reach catchment • The partial catchment is combined with selected upstream catchments and internal boundaries are dissolved • Attribution of the newly delineated watershed includes the reach code and measure of the user selected point

  18. NHD Watershed Fun Facts • Is an ArcView 3x extension • Is designed to work with NHD and the NHD ArcView Toolkit • For full functionality the user needs Spatial Analyst (a ‘watershed for confluences only’ option can be used without Spatial Analyst) • The extension, pre-processing instructions, list of available HUCs, and other related info is available on the NHD website: http://nhd.usgs.gov, under ‘Applications’

  19. NHD Watershed Characteristics: Objectives • A generic extension which helps guide users to summarize basin characteristics of choice for newly delineated watersheds • Built on top of NHD Watershed • An open, well documented script environment for users to modify as needed

  20. NHD Watershed Characteristics (cont.) • Designed as a transition tool from the general NHD Watershed environment to the specific user application environment • Not yet available on the NHD website

  21. Applications • Vermont Flood Frequency project • New Hampshire Low Flow project • Massachusetts Perennial / Intermittent Streams project

  22. Vermont Flood Frequency • USGS NH District cooperative effort with VT Department of Transportation • Regression equation estimates of peak flow for any point on any stream in Vermont • The entire state has been processed for use in the NHD ArcView Toolkit

  23. New Hampshire Low Flow • USGS NH District cooperative effort with the State’s Geological Survey • Seasonal and annual statistics for: • Ground water recharge • Low flow • Hydro-climatic data (PRISM) used extensively as a source for significant seasonal predictors including: temperature, snow fall, and precipitation

  24. Massachusetts Perennial / Intermittent Project • Needed by Mass. DEP for regulatory purposes in enforcing the State’s River Protection Act of 1996 • A logistic regression equation has been developed to determine these points • The NHD Watershed and NHD Watershed Characteristics tools are being used in batch mode to find these points and map them

  25. Watershed Characteristics • Basin area • Percent area of stratified-drift (sand and gravel) deposits • Drainage density (length of streams / drainage area) • Mean basin elevation • Percent area of forested land

  26. In the works…. • Considering the transition of the NHD Watershed and NHD Watershed Characteristics extensions to the NHDinGeo environment along with other NHD Toolkit functions • Working with NHD Watershed preprocessed datasets in the ArcHydro global tools environment

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