Arc Hydro: GIS for Water Resources
David R. Maidment
University of Texas at Austin
• Arc Hydro
– Culmination of a 3-yr effort
– GIS in Water Resources
Consortium
– Customization of ArcGIS for
water resources
– Arc Hydro toolset and
application framework
CRWR
GIS in Water Resources
Consortium
GIS
Water
Resources
Bringing together these two communities by using a
common geospatial data model
http://www.crwr.utexas.edu/giswr
ArcGIS Introduces
• A new geographic data model
• A new geographic database
Geodatabase
MS Access
Oracle
SQL Server
Informix
DB2
– Stored in an Relational
Database (Geodatabase)
• ArcObjects
– Component Object Model
(COM) objects that access
IFeature
geographic data
– Works like MS Word, Excel,
Powerpoint, ….
IFeatureBuffer
IFeatureDraw
Feature
IFeature : IRow
IFeatureBuffer : IRowBuffer
IFeatureDraw : IUnknown
What is Arc Hydro?
• An data infrastructure for storing and
integrating hydro data within ArcGIS
– A set of hydro objects built on top of
ArcObjects
– A set of standardized attributes
– A vocabulary for describing data (glossary)
– A toolset for implementing the data model
Geodatabase Model
Geodatabase
Collection of FeatureDataSets
Like a workspace
FeatureDataSet
Collection of FeatureClasses
Like a Coverage
FeatureClass
Collection of Features
Like a Coverage FeatureClass
Feature
Geographic Object
Row in DBMS Table
Features
• Features are geographic objects stored in relational
database tables
FeatureClass (table)
Stream
Feature
(row)
OID
Shape
Type
...
524
X,Y,Z,M, ...
Channel
...
• Feature location is an attribute of type shape
– Point, Multipoint, Line, Polygon
– Attributes and geometry are stored together not in
separate files as in Arc Info 7 and ArcView 3
Feature DataSets
• A holder for a set of feature
classes having a common
coordinate system and
spatial extent
FeatureClass
FeatureClass (table)
Stream
Feature
(row)
OID
Shape
Type
524
X,Y,Z,M, ...
Channel
...
...
Object Class
GeoDatabase
FeatureDataset
Extensible Data Model
Row
Feature
Measurement
NetworkFeature
Basin
JunctionFeature
EdgeFeature
SimpleJunction
ComplexEdge
Confluence
Gage
Stream
Arc Hydro Components
Drainage System
Hydro Network
Flow
Time
Time Series
Hydrography
Channel System
Hydrologic Information System
Analysis, Modeling,
Decision Making
Arc Hydro
Geodatabase
Arc Hydro Data Model
Hydrography
Hydrology
Streams
Drainage Areas
Hydrography
Channels
Terrain Surfaces
Rainfall Response
Digital Orthophotos
Data Model
Based on
Inventory
Data 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.
Integrating Data Inventory using
a Behavioral Model
Relationships between
objects linked by tracing path
of water movement
Arc Hydro USA
• Arc Hydro Framework
dataset for USA at
1:500,000 scale
• Built from USGS and
National Weather
Service data
• MonitoringPoints are
USGS stream gaging
stations
Arc Hydro geodatabase for City of Austin
Hydro response units are based on the land use map
Arc Hydro Framework Input Data
Watersheds
Waterbody
Streams
Monitoring Points
Feature
Arc Hydro Framework
Waterbody
HydroPoint
HydroID
HydroCode
FType
Name
JunctionID
!(
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!(
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ComplexEdgeFeature
!( !(
!(
HydroID
HydroCode
FType
Name
AreaSqKm
JunctionID
HydroID
HydroCode
DrainID
AreaSqKm
JunctionID
NextDownID
*
*
!(
!(
!( !(
*
Watershed
SimpleJunctionFeature
!(
!(
!( !(
!(
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!( !(
!(
HydroEdge
!(
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HydroID
HydroCode
ReachCode
Name
LengthKm
LengthDown
FlowDir
FType
EdgeType
Enabled
EdgeType
Flowline
Shoreline
1
HydroNetwork
HydroJunction
HydroID
HydroCode
NextDownID
LengthDown
DrainArea
FType
Enabled
AncillaryRole
1
Arc Hydro Framework Dataset
for the Guadalupe Basin
HydroNetwork through Canyon Lake
Flowlines through water body
Generic Junction
(for topological
connection of edges)
HydroJunction has Waterbody Relationship
National Hydro Data Programs
http://www.crwr.utexas.edu/giswr/nhdconf/nationalhydro.html
National Elevation Dataset
(NED)
National Hydrography Dataset
(NHD)
Elevation Derivatives for
National Application (EDNA)
Watershed Boundary Dataset
Hydrologic Cataloging Units (HUCS)
Guadalupe Basin
(4 HUC’s)
• 2015 HUC’s cover continental US
• average area ~ 1 county
Hydrologic Unit Code
= 12100203
Watersheds of the Guadalupe Basin
Guadalupe
HydroNetwork
TNRCC water
availability points
(water supply)
NWS forecast
Watersheds
(flooding)
EPA TMDL
Segments
(water quality)
Regional Analysis
HydroNetwork to
provide connectivity of
flow through large
regions
Digital elevation model
for terrain analysis within
basins
Scales of representation of Drainage Systems
Basins – drainage areas for water
resources management
Watersheds – subdivision of Basin
for a particular hydrologic purpose
Catchments – subdivision of
Basin into elementary drainage
areas by physical rules
Digital Elevation Model –
land surface terrain grid cells
Catchments, DrainageLines and
DrainagePoints
Catchments Subdivided at Watershed Outlet
Area to Area Navigation
EDNA Catchments
Average area = 7.5 km2
Designed for remapping of Nexrad
data onto drainage units
Arc 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
Intrinsic Hydrologic Modeling
• Dr Tarboton
– DEM-based
hydrologic modeling
• Mean annual flows
and pollutant loads
• USGS
– Stream Stats
Streamstats
http://ststdmamrl.er.usgs.gov/streamstats/expert.htm
Interfaces to Arc Hydro Data and Models
Analysis, Modeling,
Decision Making
Arc Hydro
Geodatabase
Dynamic Linked Library
Can have
Fortran
subroutines
in a DLL
Muskingum
flow routing
Independent Hydrologic Model
VB progam reads and writes
text files
OVERVIEW OF MULTI– HAZARD FLOOD MAP MODERNIZATION
The “NOW”:
Components of a DFIRM
BASE
+
TOPOGRAPHY
+
FLOOD DATA
= DFIRM
FEDERAL EMERGENCY M ANAGEMENT AGE NCY
12
Flood Hydrology and Hydraulics
ArcView
Input Data
DEM
HEC-GeoHMS
HEC-HMS
Flood
discharge
ArcView
Flood
plain maps
Hec-GeoRAS
HEC-RAS
Water
surface
profiles
Austin Digital Elevation Model
Waller Creek
Austin Watersheds
DEM Watersheds for Austin
Selected Watersheds and Streams
Mansfield Dam
Colorado
River
HMS Schematic Prepared with
HEC-GeoHMS
Mansfield Dam
Colorado
River
HMS Model of the Austin Region
HMS Results
Watershed 155
Junction 44
Colorado River Network
1:100,000 scale
Developed from
National Hydrography Dataset
City of Austin Stream Network
Developed from 1”=100’
Capco Areal photogrammetry
1:1200 scale
Stream Definition: Waller Creek
Austin Watersheds with Streams
derived from Aerial Photographs
Streamlines generated
by the aerial
photographs are not
always continuous.
Waller Creek HMS Model
Connecting HMS and RAS
Hydrology
Model defines
flows
(HMS)
Hydraulic
Model defines
water surface
elevations
(RAS)
Flood Hydrology and Hydraulics
ArcView
Input Data
DEM
HEC-GeoHMS
HEC-HMS
Flood
discharge
ArcView
Flood
plain maps
Hec-GeoRAS
HEC-RAS
Water
surface
profiles
Flood Plain Mapping
HEC-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
Normal Water Surface
Flood Water Surface
Floodway
Left Bank Station
Floodway
Main
Channel
Right Bank Station
Waller Creek
Watersheds
Network
Channel
HEC-RAS: Output
Graphical
Text File
Floodplain Mapping: Plan View
3D Terrain Modeling: Ultimate Goal
What software do you need?
• ArcView 8.2
– Viewing, querying existing geodatabases
– Editing feature classes and adding data
• Spatial Analyst for ArcGIS
– To operate the raster tools in Arc Hydro
• ArcInfo 8.2
– To build geometric networks and create new
relationships
Arc Hydro Tools Version 1.0
• Raster processing
– DEM processing
– Watershed delineation
• Vector processing
– Arc Hydro attributes
– Network analysis
• Time Series and
Application Utilities
• Buttons
Status of the
HEC-related Software
• HEC-GeoHMS ver 1.0 available from HEC for
ArcView version 3 (version 1.1 to be released
soon) http://www.hec.usace.army.mil/software/software_distrib/geohms4arcview/geohmsprogram.html
• Arc Hydro terrain and watershed functions replace
some but not all of HEC-GeoHMS
• HEC-GeoRAS ver 3.0
http://www.hec.usace.army.mil/software/software_distrib/georas4arcview/georasprogram.html
• ESRI has developed a beta-version of GeoRAS for
ArcGIS (integrated with Arc Hydro)
Tools (Dean Djokic)
Arc Hydro Time Series Object
TSDateTime
TSValue
FeatureID
TSType
National Water Information System
Web access to USGS
water resources data
Arc Hydro NWIS data
retrieval tool
Streamflow Information in Space and Time
Current
Future Possibilities
Time
Real Time data
Historical daily
mean discharge
Streamstats
Streamflow
statistics
At Gages
Space
Anywhere on a Stream
HydroID and HydroCode
Retrieving NWIS Data
• Select Gage
Layer
• Enter Period of
Record
Streamflow Time Series
Arc Hydro Time Series Table
Time Series Extracted to Excel
(In Excel, use Data/Get External Data to query Geodatabase)
Excel
view
Geodatabase
view
HRAP Cells for Nexrad Data
Average area = 14.5 km2
Coupling Spatial and Temporal Data
1 hour Nexrad Rainfall
on the Guadalupe Basin
October 13, 2001
Water Balance in the Landscape
Atmospheric Water
Precipitation
Evaporation
Runoff
Soil Water
Surface Water
Recharge
Baseflow
Groundwater
EDNA Catchments
Average area = 7.5 km2
Intersection of Nexrad and
Catchments
Surface Water Balance
Atmospheric Water
Soil Water
Surface Water
Modflow Groundwater Cells
Modflow Model of the
Edwards-Trinity
aquifer
Average area = 2.6 km2
Intersection of Nexrad and
Modflow Cells
Atmospheric Water
Groundwater
Balance
Groundwater
Intersection of Nexrad,
Catchments and Modflow
Atmospheric Water
Soil Water
Surface Water
Groundwater
DHI Tools for TimeSeries
Management and Analysis
– Manages TimeSeries Data at the GeoDatabase level
• An ArcHydro based GeoDatabase
• Import from a variety of formats (DHI, USGS, text file)
• Query for Data Types
– Manages TimeSeries Data for Features
• Plot
• Statistics
• Query for Time Periods
– Performs Calculations and Analysis
• Mean Area Rainfall
– Thematic groups of time series
• Water Users (Industrial, Irrigators)
• Data Types (Rainfall, Evaporation)
Import TimeSeries
HEC USGS
dfs0
USGS Bridge
HEC Bridge
dfs0 Bridge
Slides provided by Michael Blongewicz,
DHI Water and Environment, Denmark
Geo
Database
Manage TimeSeries Data within
ArcMap
At the GeoDatabase level
At the Feature level
Feature based; update Properties,
plot, statistics
Geoprocessing and Terrain
Analysis (Steve Kopp)
River Modeling

River hydraulic modeling provides a tool to
study and gain understanding of hydraulic flow
phenomena

Topographic data describe the geometry of the
simulated river system and permit the
establishment of model topology

HEC-RAS, MIKE 11 hydraulic models require
channel information for model development
River Morphology
Flood Inundation
Floodplain Delineation
Floodplain Delineation
Channel and Cross-Section
Direction of Flow
Channel
Cross-Section
ProfileLines
Types
1- Thalweg
2- LeftBank
3- RightBank
4- LeftFloodLine
5- RightFloodLine
ProfileLines and CrossSections are linked through Channel_ID
TIN as a source of cross-sections
CrossSections
Data for channels
• Bathymetry data for channels mainly
include points with (x,y,z) attributes.
• Data can be collected using
–
–
–
–
Traditional methods (surveying)
Depth sounder (using a boat)
LIDAR ( Light Detection and Ranging)
SAR (Synthetic Aperture Radar), etc.
Data analysis
(Research of Venkatesh
Merwade, CRWR)
Centerline/Thalweg
Cross-sections
ProfileLines
Start with points
Extract all the
Create surface
from points necessary information
How do we do this…….
Defining a Thalweg
Input
User defines
an arbitrary
centerline
over the
measurement
points
Step 1
Thalweg tool
creates a
surface using
the
measurement
points
Step 2
Densify the
initial
centerline to
get more
points
Old vertices
New vertices
Step 3
Normals are
drawn at each
vertex of the
centerline to
locate deepest
points
Step 4
All the
deepest
points
replace the
vertices of
the old
centerline
Output
Final
result is a
3D
polyline
defining
the
thalweg
Measure in ArcGIS
A PolylineMZ can store
m and z at each vertex
along with x and y
coordinates.
0
64.0056
112.3213
Coordinate Transformation
m is measure along
the centerline
r is distance across the
river from the
centerline
Sinuous river becomes
straight when
transformed into (m,r)
co-ordinates.
A “straightened” channel!
r
y
m
x
Coordinates measured
along and across the channel
Northing and Easting Coordinates
Surface in transformed
co-ordiantes
Straightened river
Profile line and cross-sections
Sinuous river
Straightened channel
as a 3D Fishnet
Transform the data back to x,y
coordinates
Original river in X,Y
Profile lines and cross-sections in (x,y)
created using FishNet in (m,r).
Profile Lines and Cross Sections in 3D
Bird’s eye view!
Breaklines
• Profile lines are actually breaklines but they
are created using a surface.
• Need a methodology to create breaklines
before generating a surface (especially TIN)
in order to handle false dams.
GIS for River Channels
Measurement points
Thalweg/Centerline
Cross-sections
Fishnet
ProfileLines
Surface
Develop generic ways to create all the channel features from
measurement points. This task is almost finished.
Cross-sections comparison
Cross-section without breaklines
Cross-section with breaklines
Both cross-sections are created using a TIN.
Channel Movie
The channel of the Brazos River near Sealy, TX.
Bathymetry is recorded using a depth sounder from a boat.
Land surface is represented using NED and DOQ