1. Integrating ArcHydro and HEC Models by David R
Integrating ArcHydro and HEC Models by David R. Maidment Center for Research in Water Resources University of Texas at Austin
Arc Hydro and hydrologic models
Interface Data Model for HEC-HMS
Implementation in San Antonio using Model Builder

2. Integrating Arc Hydro and HEC Models
Arc Hydro and hydrologic models
Interface Data Model for HEC-HMS
Implementation in San Antonio using Model Builder

3. Hydrologic Information System
Modeling
Geodatabase
A hydrologic information system is a combination of geospatial and temporal hydrologic data with hydrologic models that supports hydrologic practice, science and education

4. GIS Preprocessors for Hydrologic Models
Interface Programs
HMS
Geo
HMS
Database
RAS
Geo
RAS

5. Connecting Arc Hydro and Hydrologic Models
GIS
Interface data models
HMS
HMS
IDM
Geo
Database
Arc Hydro
data model
RAS
RAS
IDM

6. Connecting Arc Hydro and Hydrologic Models
GIS
Interface data models
HMS
HMS
IDM
GeoHMS
Geo
Database
Arc Hydro
data model
GeoRAS
RAS
RAS
IDM

7. Integrating Arc Hydro and HEC Models
Arc Hydro and hydrologic models
Interface Data Model for HEC-HMS
Implementation in San Antonio using Model Builder

8. Basin
Interface
Data
Model

9. Project
Interface
Data
Model

10. IDM Performance Goal
To provide a database for all HMS data, so that the data may be queried and retrieved efficiently.

11. IDM Data Transfer Goal
To store data in a manner so that it is readily transferable from geodatabase to HMS files, and visa versa.
HMS files
HMS geodatabase

12. IDM Spatial Analysis Goal
To store watershed (spatial) data in a manner that can be easily viewed and analyzed in ArcMap.

13. IDM Intuitive Use Goal
To create a data structure that is logical to the HEC-HMS user

14. IDM Arc Hydro Compliance Goal
Arc Hydro connectivity and naming conventions
Arc Hydro
Geodatabase
IDM
Geodatabase
HEC-HMS
Program files
HydroID
FeatureID
HMSCode
Element Names

15. The HMSCode IDM Flow Network .basin HMS text file
Connection between HMS feature classes and parameter tables
Connection between HMS and IDM elements
HMSSubbasin attribute table
HMSInitialConstant table
IDM

16. IDM Geodatabase Design
Purpose: To provide a HMS data storage structure that meets IDM design goals
Visio 2000 UML
ArcGIS Repository
Geodatabase Schema

17. UML
The Unified Modeling Language

18. UML
UML Diagram
Geodatabase Table

19. Basin
GDB

20. Project
GDB

21. Importing HMS Data
Use Visual Basic to develop codes for transferring data.

22. Constant Loss Rate (inches/hour)
Llano at Junction Model
Rainfall lost to infiltration

23. Snyder Time to Peak (hours)
Llano at Junction Model
Time to Peak

24. Modified Puls Storage (ac-ft)
Llano at Junction Model
Storage required to produce 5000 cfs flow

25. Integrating Arc Hydro and HEC Models
Arc Hydro and hydrologic models
Interface Data Model for HEC-HMS
Implementation in San Antonio using Model Builder

26. Regional Storm Water Modeling Program and Master Plan for San Antonio
City of
San Antonio
Good morning.
It’s my pleasure to share with you an example of regional cooperation within Bexar County.

27. San Antonio Regional Watershed Modeling System
Geospatial Data:
City, County
SARA, other
“Bring the models
together”
Modeling
System
Rainfall Data:
Rain gages
Nexrad
Calibration Data:
Flows
Water Quality
Floodplain
Management
Capital
Improvement
Planning
Water quality
planning
Integrated
Regional Water
Resources planning
Flood
Forecasting

28. Sources of Rainmap data
Historical Nexrad data – NWS and TNRIS archive
Design rainfall maps – 2, 5, 10, 25, 50, 100 year design rainfalls as used for FEMA floodplain studies
Real-time Nexrad data using web services (Tom Wesp)

29. NEXRAD WSR-88D Radars in Central Texas (Weather Surveillance Radar-1988 Doppler) scanning range = 230 km
NEXRAD Products:
Stage I: Just Radar
Stage II: gages, satellite, and surface temperature
Stage III: Continuous mosaic from radar overlaps
One of the strong motivation points for integration is the availability of
good quality precipitation estimates at higher temporal and spatial resolutions to feed engineering models!!
In particular the NEXRAD products of the NWS that now provide “true spatial realizations of rainfall fields”
With historical and real time sources
EWX – NEXRAD Radar in New Braunfels
Source: PBS&J, 2003

30. Digital Rain Maps from National Weather Service (03/04/2004)

31. Digital Rain Maps from National Weather Service (03/29/2004)

32. Reading Historical Archives of NEXRAD Datasets from Internet
FTP Server
Internet
Local

33. Design Rainfall Maps 100yr 06h 100yr 12h 100yr 24h
But, how to get variation of intensity with time??
We also need the design precipitation hyetograph to obtain reliable design discharge hydrographs
We may explore “hyetograph analysis” to get a theoretical hyetograph shape
Using the Alternating Block Method or Instantaneous Intensity Method

34. Real-Time NEXRAD Datasets from Web Services

35. FEMA 100-year flood plain map in Bexar County

36. Regional Watershed Modeling System Case Study
Salado Creek
watershed
Components:
Arc Hydro Geodatabase
for whole watershed
HEC-HMS hydrology model
HEC-RAS hydraulic model
for Rosillo Creek
Bexar County
Rosillo Creek watershed

37. Arc Hydro and HEC-HMS HEC-HMS Hydrologic Model Arc Hydro Schematic
Network
Calculates
Flows

38. Arc Hydro and HEC-RAS HEC-RAS Hydraulic Calculates Water Surface
Model
Calculates
Water Surface
Elevations
Arc Hydro
Channel
Cross Sections

39. HEC Data Storage System (DSS) (binary data file system shared by HEC models)
An exact replica of the binary DSS files is stored in the ArcGIS geodatabase
An Arc 9 Toolbox exchanges data between DSS and the geodatabase
Time series
catalog
Many time series

40. Flow Change Points Models communicate with
one another through Arc Hydro
at designated points

41. Nexrad Map to Flood Map in Arc 9 Model Builder
FLOODPLAIN MAP
Flood map
as output
Model for
flood flow
HMS
Model
for flood
depth
Nexrad rainfall map as input

42. Conclusions
An interface data model provides a convenient way of storing and visualizing the content of a hydrologic model
Combination of interface data models and ArcGIS Model Builder provides a very efficient means of work flow automation