A general description of the tools and the NMSU geography educational resources available to New Mexico Flood Waters Association personnel.

1. Arc Hydro: An Introduction
Michael N. DeMers
Department of Geography
New Mexico State University

2. Arc Hydro
• Extension of geodatabase model for support
of water resources applications (template data
model)
–Surface and groundwater
• Collection of tools for support of Arc Hydro
geodatabase design and basic water
resources functions
• Starting point for water resources database
and application development

3. Arc Hydro Data Model

4. Data Model Purpose
• Target audience: Water resources community
interested in quick start in ArcGIS
implementation
• Starting point for project model design
• Not a “do all” design
• Not implementation/application specific, but
provides the key components upon which to
develop your implementation
• Not a numerical but a DATA model
–Allows support for many models

6. Describing the Hydrologic Cycle

7. Arc Hydro Framework Data Model
Surface water features
Groundwater features
Time Series

9. Arc Hydro Data Model Details

10. Time Series Components

11. Basic Concepts
• Define core feature classes for water resources analyses
– Inventory of relevant spatial elements
• Establish relationships between core feature classes
– So we know what is connected to what
• Use geometric network for tying pieces together
– So we can trace upstream/downstream
• Mobilization of standard ArcGIS functionality
• Custom tools for some of the attribute management
• Custom tools for advanced “water resources”
functionality

12. Application and use of Arc Hydro for a Water
Geofabric
1. Build and compile key GIS
Databases
2. Build and serve key Digital
Basemaps
3. Build and serve Operational
Layers
4. Build and serve
Tasks
5. Build and serve key
GIS Applications
GIS Application
Operational layers
Digital Basemap (2D or
3D)
Tasks that operate
against . . .
. . . a fully operational
GIS database
(a Geofabric)

13. Scalability
1:17,000,000
1:5,000,000
1:2,500,000
1:500,000
1:175,000
1:40,000
1:24,000
1:5,000

14. Arc Hydro Tools

15. Key Concepts
• Transitions between the raster and vector worlds –
integrated operations
• “Relationships between objects linked by tracing path of
water movement”
Raster NetworkVector
Logical SchemaExtended Network

16. Terrain Processing
• Start with the terrain
model
• Identify drainage
patterns
• Identify catchments

17. Network Generation
• Start with the drainage
pattern
• Define hydro edges
from drainage lines
• Generate junctions at
confluences
• Build the geometric
network

18. Connecting Catchments to Junctions
• Start with the catchments
• Identify drainage
points
• Link drainage points
to junctions

19. Extended (Hydrologic) Network
• Combination of hydro
network and drainage
areas connected through
junctions.
• Allows tracing through
network and selection
on drainage areas

20. Node-Link Schematization
• Start with the catchments
• Find centroids
• Continue with drainge
lines
• Find confluences
• Connect nodes

21. • Transition from geo
representation to logical
representation
Node-Link Schematization
• Support for various
modeling efforts

22. Arc Hydro Tools
• 70 + functions currently available
–Watershed Delineation
–Batch Terrain Preprocessing
–Schema Creation
–Parameters Accumulation
–Parameters Computation (e.g. mean elevation, 10-
85 slope, etc.)
–Time Series

23. Arc Hydro Tools
• Functions developed during projects are integrated
into the Arc Hydro tools (needs driven development)
–Batch Terrain Preprocessing
–Parameters Computation
–Terrain Morphology
–and others…

24. Process Automation in Model Builder
Arc Hydro Model For Hydro Landscape Characterization

25. Many Aspects of Arc Hydro
Saxe, John Godfrey, 1963, “The Blind Man and the
elephant”, New York: Whittlesley House
Database
design
Application
“Standard”
Tools
Marketing
Development
environment
Elephant illustration ©2002 Jason Hunt
www.naturalchild.org/jason

26. “Why Should I Care” about Arc Hydro ?
• Economy of development
–Why reinvent the wheel?
–Established configuration methodology
–Established development framework
• Industry “standard”
–Fundamental geodatabase design principles
implemented for water resources theme
–Established techniques rolled into a publicly
available utility
–Tested and accepted
• Training and support
• Free maintenance – ESRI’s commitment to the
water resources community

27. Where To Begin

29. Where to Learn More

32. Alternative to ArcHydro