Title: Arc Hydro and Modeling
1Arc Hydro and Modeling
- Intrinsic Modeling within a particular
application eg Excel, ArcGIS - Dynamic Linked Library tightly coupled package
of functions (e.g. LibHydro from HEC) - Independent Modeling separate hydrologic model
with data exchange
2Streams Drainage Areas Hydrography Channels
Terrain Surfaces Rainfall Response Digital
Orthophotos
Thematic Layers supporting the Arc Hydro data
model (from Michael Zeiler Modeling Our World
Volume 2)
3Data Model Based on Behavior
Follow a drop of water from where it falls on the
land, to the stream, and all the way to the ocean.
4Integrating Data Inventory using a Behavioral
Model
Relationships between objects linked by tracing
path of water movement
5Intrinsic Hydrologic Modeling
- Dr Tarboton
- DEM-based hydrologic modeling
- USGS
- Stream Stats
- Mean annual flows and pollutant loads
Streamstats
http//ststdmamrl.er.usgs.gov/streamstats/expert.h
tm
6Dynamic Linked Library
Can have Fortran subroutines in a DLL
Muskingum flow routing
7Independent Hydrologic Model
VB progam reads and writes text files
8Interfaces to Arc Hydro Data and Models
Excel
ArcGIS
Relational Database (Access)
Visual Basic
9ArcGIS Development at DHI
- Extend the ArcGIS Hydro Data Model
10DHI TimeSeries Package
- TimeSeries Package Architecture
11Three basic water problems
- Too little water (Drought and water supply)
- Too much water (Flooding)
- Its dirty (Water Quality)
Also have significant GIS effort on environmental
issues related to water such as habitat
assessment
121996 Texas Drought
- George W. Bush, (then Governor of Texas) asked
Tell me how much water we have, how much water
were using and how much water we need - State water officials did not have adequate
answers
13Texas Water Planning
- 1997 Texas Legislature passed Senate Bill 1 which
provided for - State-wide geospatial data development
(topography, hydrography, land use, soils and
orthophotos) - Water planning in 14 regions rather than
state-wide - Assessment of water availability for all water
permits
14Hydrologic Cataloging Units (HUCS)
Hydrologic Unit Code 12100203
Guadalupe Basin (4 HUCs)
- 2015 HUCs cover continental US
- average area 1 county
15Water Availability in the Guadalupe Basin
Estimate water availability at each legally
permitted water diversion point based on
naturalized flow at stream gages and the
effects of other permitted diversions
16Digital Elevation Model
San Marcos basin
National Elevation Dataset 30m x 30m
cells 11,000,000 cells to cover San Marcos
basin 70,000,000 cells to cover Guadalupe basin
17Drainage Area Delineated from the Digital
Elevation Model
Arc Hydro attribute DrainArea
18Estimating Naturalized Flow at Diversion Points
Naturalized flow record at stream gage (50
years of monthly flows)
Qf
Af
Qd
Estimated flow record at diversion point
Ad
19Length Downstream
Flow distance (D to F) Length Downstream
(D) Length Downstream (F)
Length Downstream (F)
F
D
D
Seepage losses
F
Length Downstream (D)
Arc Hydro attribute LengthDown
20Water Availability Modeling
Letter to each water permit owner specifying of
permitted flow available during a drought
Completed for 10,000 water permit holders,
1998-2002
21Water Availability Assessment (completed for
10,000 permit holders, 1998-2001)
Texas Natural Resources Conservation Commission
Hydrologic modeling by engineering consultants
Letter to each water permit owner specifying of
permitted flow available during a drought
Geospatial data development by Center for
Research in Water Resources, Univ. of Texas
22Flood Hydrology and Hydraulics
ArcView Input Data DEM
ArcView Flood plain maps
HEC-GeoHMS
Hec-GeoRAS
HEC-RAS Water surface profiles
HEC-HMS Flood discharge
23Status of the Software
- HEC-GeoHMS ver 1.0 available from HEC for ArcView
version 3 http//www.hec.usace.army.mil/software/s
oftware_distrib/geo-hms4arcview/geohmsprogram.html
- Arc Hydro terrain and watershed functions replace
some but not all of HEC-GeoHMS - HEC-GeoRAS ver 1.0 http//www.hec.usace.army.mil/s
oftware/software_distrib/geo-ras4arcview/georaspro
gram.html - ESRI has developed a beta-version of GeoRAS for
ArcGIS
24Austin Digital Elevation Model
Waller Creek
25Austin Watersheds
26CRWR-PrePro (a precursor of HEC-GeoHMS)
Digital Elevation Model Stream Map
ArcView-based preprocessor for HEC-Hydrologic
Modeling System (HEC-HMS)
Control point locations
Soil and Land Use Maps
HMS Basin File
27DEM Watersheds for Austin
28Selected Watersheds and Streams
Mansfield Dam
Colorado River
29HMS Schematic Prepared with CRWR-PrePro
Mansfield Dam
Colorado River
30HMS Model of the Austin Region
31HMS Results
Watershed 155
Junction 44
32Flood Hydrology and Hydraulics
ArcView Input Data DEM
ArcView Flood plain maps
HEC-GeoHMS
Hec-GeoRAS
HEC-RAS Water surface profiles
HEC-HMS Flood discharge
33Colorado River Network
1100,000 scale Developed from National
Hydrography Dataset
34City of Austin Stream Network
Developed from 1100 Capco Areal
photogrammetry 11200 scale
35Stream Definition Waller Creek
Austin Watersheds with Streamsderived from
Aerial Photographs
Streamlines generated by the aerial photographs
are not always continuous.
36Information for Correcting Stream Network
- DEM
- Contours
- Storm sewers
- Orthophotos
37Resulting Corrected Stream
- Subsequent steps
- Verification of corrected streams by flood
hydrologists. - Running tracer program to connect arcs.
- Burning of streams into DEM.
38Waller Creek HMS Model
39Flood Plain Mapping
40 Connecting HMS and RAS
41Flood Hydrology and Hydraulics
ArcView Input Data DEM
ArcView Flood plain maps
HEC-GeoHMS
Hec-GeoRAS
HEC-RAS Water surface profiles
HEC-HMS Flood discharge
42HEC-RAS Background
- River Analysis System model of the U.S. Army
Corps of Engineers - Input cross-section geometry and flow rates
- Output flood water elevations
Cross-Section Schematic
43Waller Creek
Watersheds
Network
Channel
44HEC-RAS Cross-Section Description
- Points describe channel and floodway geometry
- Bank station locations
- Water surface elevations and floodplain
boundaries
45Discharge at a Particular Cross-Section
46HEC-RAS Output
47Floodplain Mapping Plan View
483D Terrain Modeling Ultimate Goal