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This workshop focuses on loading data into ArcHydro and building the global geodatabase directory structure, including importing data, creating hucpoly and hucpoint features, building the global network, and assigning HydroID's.
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Loading Data into ArcHydro Building the Global GeoDatabase
Directory Structure StreamStats Data Prep Workshop Oct 21-22, 2003
Global Network StreamStats Data Prep Workshop Oct 21-22, 2003
Global Data Sets • All in Global.mdb geodatabase • hucpoly (tile boundaries) • streams (network to connect tiles) • hucpoints (outlets for tile polys) StreamStats Data Prep Workshop Oct 21-22, 2003
Step 1: Create Empty Geodatabase StreamStats Data Prep Workshop Oct 21-22, 2003
Step 2: Import data • First import a data set covering ENTIRE area, i.e. all HUCs you plan to use • This sets up the maximum spatial extent we can put into the “feature dataset” • Make sure this data set at least covers the full desired extent StreamStats Data Prep Workshop Oct 21-22, 2003
The Import Coverage Tool Type in “Layers here click StreamStats Data Prep Workshop Oct 21-22, 2003
Don’ttouch! click Set to areasonable value StreamStats Data Prep Workshop Oct 21-22, 2003
Building Global hucpoly • Ideally no overlaps or gaps • Should be derived from fdr by delineation • Start by delineating from outlet of each HUC • Convert to a grid StreamStats Data Prep Workshop Oct 21-22, 2003
Building Global hucpoly (continued) • Remove overlaps at top of non-headwaters HUCs via map algebra • Convert to a shapefile hucshp in huc folder • When finished, load shapefiles into global hucpoly feature class StreamStats Data Prep Workshop Oct 21-22, 2003
Building the hucpoint feature class • These basically are the outlet points for each HUC • You need one for each HUC, including the HUC furthest downstream • Build these in ArcMap Editor StreamStats Data Prep Workshop Oct 21-22, 2003
Building the Global Network • Must build a Geometric Network of streams • Just need mainstem streams needed to connect our data tiles (8-digit HUCs) • Coastal streams, and any stream not connecting an upstream HUC can be deleted StreamStats Data Prep Workshop Oct 21-22, 2003
Geometric Network Wizard • Build from existing features • Use hucpoint and streams feature classes • Name network HUC_Net • Build complex edges from streams feature class • Use 2-m snap tolerance, both sets of features • Include sources and sinks on hucpoints • Do not assign weights StreamStats Data Prep Workshop Oct 21-22, 2003
Set Flow Directions on Network • Select outlet hucpoint • Set Ancillary Role to Sink • Click Set Flow Direction button on Utility Network Analyst Toolbar • Or if streams from NHD, use ArcHydro Tools, set flow opposite feature directions StreamStats Data Prep Workshop Oct 21-22, 2003
Assign HydroID’s StreamStats Data Prep Workshop Oct 21-22, 2003
Make Relationship Class HUCHasJunction StreamStats Data Prep Workshop Oct 21-22, 2003
Make Relationship Class HUCHasJunction StreamStats Data Prep Workshop Oct 21-22, 2003
Store Area Outlets • ArcHydro Tools Toolbar • Attribute Tools pulldown • Or assignmanually StreamStats Data Prep Workshop Oct 21-22, 2003