Arc Hydro Groundwater Data Model

1
Arc Hydro Groundwater Data Model

• This presentation is adapted from the Groundwater
  Preconference Seminar presented at the 2008 ESRI
  User Conference by David Maidment, Gil
  Strassberg, and Norman Jones
• The research described here is based on the PhD
  dissertation of Gil Strassberg, which is
  accessible at
• ftp//ftp.crwr.utexas.edu/pub/outgoing/strassberg/
  GroundwaterDataModel/Documents/Dissertaion_Strassb
  erg.pdf

2
What is a hydrologic data model
Booch et al. defined a model a simplification
of reality created to better understand the
system being created
Objects
Aquifer
Stream
Well
Volume
R.M. Hirsch, USGS
3
Developing a groundwater data model
Take a variety of spatial information and
integrate into one geospatial database with a
common terminology

• Better communication
• Integration of data
• Base for applications

4
Components
Components can be added to the framework to
represent specific themes in more detail
Surface water components
Groundwater components
Network
Geology
Framework
Drainage
Borehole data
Hydrography
Hydrostratigraphy
Channel
Simulation
Temporal (enhanced)
5
Arc Hydro GW Data Model
6
Arc Hydro Framework

• Basic representation of surface water and
  groundwater
• Components can be added to the framework to
  represent specific themes in more detail

7
Well

• Wells are the most basic features in groundwater
  databases
• Attributes of wells describe its location, depth,
  water use, owner, etc.

8
Well

• Wells are defined as 2D point features
• Only some basic attributes are predefined to
  describe the well use, and geometry and
  relationship with aquifers

Wells in the Edwards Aquifer
9
Aquifer features

• Polygon features for representing aquifer
  boundaries and zones within them
• Representation of Aquifer maps

10
Aquifer features

• An aquifer is defined by one or a set of polygon
  features
• Aquifer features can be grouped by HGUID

11
Hydro Features

• Key attributes for feature identification
• HydroID Unique ID within the geodatabase
  (internal relationships)
• HydroCode Public identifier (external
  relationships)

12
HydroID

• A new ID assigned to features in a Arc Hydro
  geodatabase
• Uniquely identifies features with a geodatabase
• Is used to manage relationships between features
  and to relate features with tabular data (e.g.
  time series)
• Custom tool for managing HydroIDs

13
HydroCode links to external applications

• Web interface for groundwater data in Texas
• Texas Water Information Integration
  Dissemination (WIID)

14
Aquifer and well

• Well features are related to Aquifers The
  AquiferID of a well feature is equal to the
  HydroID of an aquifer feature
• An aquifer can be associated with one or more
  wells (1M relationship)
• Can take a different approach to support MN
  relationship

15
Aquifer and well
Well HydroID 53
16
Wells and TimeSeries
Well features are related with time series (water
levels, water quality)
17
MonitoringPoint has time series
Monitoring points are related with time series
(streamflow, water quality, precipitation)
18
Integration of surface water and groundwater data
The common framework supports analysis of surface
water and groundwater data together
Well in the Edwards Aquifer)
Streamflow Gage at Comal Springs, New Braunfels
Texas
19
Surface water groundwater linkage
Relationships between surface water and aquifer
enable analysis based on spatial and hydrologic
relationships
Streams over the outcrop recharge features
20
Components

• Geology - Representation of data from geologic
  maps
• Wells and Boreholes Description of well
  attributes and borehole data
• Hydrostratigraphy 2D and 3D description of
  hydrostratigraphy
• Temporal Representation of time varying data
• Simulation Representation of groundwater
  simulation models (focus on MODFLOW)

21
Geologic maps
A geologic map is a cartographic product that
portrays information about the geologic character
of a specific geographic area

• Groundwater features are closely tied to geology
• Geologic maps vary in scale (continental,
  regional, local)
• Provide a simple data structure to support
  mapping

Geology
Aquifers
Maps from the United States National
(http//nationalatlas.gov/).
22
Geologic map databases
A digitally-compiled collection of spatial
(geographically referenced) and descriptive
geologic information about a specific geographic
area (Geologic Data Subcommittee, Federal
Geographic Data Committee 2006)

• Standards for archiving geologic map data
• Support the development of applications for
  automating map creation
• Complex
• Examples
• North American Geologic Map Data Model (NADM)
• National Geologic Map Database (NGMDB)
• State geologic map databases (e.g. Geologic Atlas
  of Texas)
• ArcGeology

23
Geologic map databases
Geodatabase design for storing data from the
Geologic Atlas of Texas (http//www.tnris.org/news
.aspx?id244)
Arc Geology generic geologic map database
implemented within ArcGIS (figure from Raines et
al. 2007
24
Geology component
GeologyPoint Point feature (e.g. springs, caves,
sinks, and observation points) GeologyLine Line
features (e.g. faults, contacts, and
dikes) GeologyArea Areal features (e.g. rock
units and alteration zones)
Map modified from Geologic map of the Edwards
Aquifer recharge zone, south-central Texas. U.S.
Geological Survey SIM 2873
25
Components

• Geology - Representation of data from geologic
  maps
• Wells and Boreholes Description of well
  attributes and borehole data
• Hydrostratigraphy 2D and 3D description of
  hydrostratigraphy
• Temporal Representation of time varying data
• Simulation Representation of groundwater
  simulation models (focus on MODFLOW)

26
Well databases

• Wells are basic features in groundwater databases
• Attributes of wells describe its location, depth,
  water use, owner, etc.
• Data are collected from drilling/construction
  reports and permits

27
Well databases

• Well databases store information on wells and
  related data
• Data are related to wells such as construction,
  water levels, water quality, and stratigraphy
• Usually a central table is used to describe well
  features and other data are linked to it through
  key attributes (e.g. state well number)

Relationships in the TWDB groundwater database
28
Well

• The Well location is defined as a 2D point in the
  Well feature class
• In the Arc Hydro model we only predefine a set of
  basic attributes

Wells in the Edwards Aquifer
29
Borehole data

• 3D data (screens, completion intervals,
  stratigraphy) is referenced along the well
• From depth (top) To depth (bottom)

30
BoreholeLog table

• Used to store 3D borehole data related with well
  features
• Each row in the table represents a point/interval
  along a borehole
• Data are related with a Well feature through the
  WellID attribute
• 3D geometry is defined by the TopElev and
  BottomElev attributes

31
3D features (BorePoints and BoreLines)

• Can create 3D features representing data in the
  BoreholeLog table
• BorePoint is a 3D point feature class for
  representing point locations along a borehole
  (e.g. geologic contacts, samplers)
• BoreLine is a 3D line feature class for
  representing intervals along a borehole

32
Components

• Geology - Representation of data from geologic
  maps
• Wells and Boreholes Description of well
  attributes and borehole data
• Hydrostratigraphy 2D and 3D description of
  hydrostratigraphy
• Temporal Representation of time varying data
• Simulation Representation of groundwater
  simulation models (focus on MODFLOW)

33
Hydrogeologic units

• Hydrogeologic unit is any soil or rock unit or
  zone which by virtue of its hydraulic properties
  has a distinct influence on the storage or
  movement of ground water (USGS glossary of
  hydrologic terms)

Hydrogeology can be derived by classifying
stratigraphic units
Stratigraphic units
Hydrogeologic units
Upper confining unit
Georgetown Fm.
Georgetown Fm. (GTOWN)
Cyclic Marine member (CYMRN)
Pearson Fm.
Leached collapsed member (LCCLP)
Edwards Aquifer
Regional dense member (RGDNS)
Grainstone member (GRNSTN)
Kirschberg evaporite member (KSCH)
Kainer Fm.
Dolomitic member (DOLO)
Basal Nodular member (BSNOD)
Upper Glen Rose (UGLRS)
34
Hydrogeologic unit table

• HydroGeologicUnit table provides a conceptual
  description of hydrogeologic units
• Hydrogeologic units are with an AquiferID such
  that they can be grouped to represent an aquifer
• Spatial features are indexed with a HGUID to
  relate to the conceptual representation of the
  units

35
Representations of hydrogeologic units

• Different spatial representations of
  hydrogeologic with 2D and 3D objects
• Workflow for creating 3D hydrogeologic models

36
Hydrogeologic unit table

• Hydrogeologic units are described with different
  spatial instances (outcrops, borehole intervals,
  surfaces, cross sections, and volumes)
• HGUID is the key attribute

37
HGUArea

• 2D polygons defining boundaries of hydrogeologic
  units
• HGUArea (conceptual/interpolated boundary) ?
  GeologyArea (mapped outcrop)

GeologyArea features represent data from geologic
maps
GeologyArea
Data points representing top elevations of the
Kainer formation
GeoArea feature representing the Kainer
hydrogeologic unit
38
Representation of Cross Sections

• SectionLine defines the 2D cross section
• GeoSection represent 3D sections as 3D polygons
• SectionID of the polygon relates back to the
  section line

39
GeoRasters

• Raster catalog for storing and indexing raster
  datasets
• Can store top and bottom of formations
• Each raster is related with a HGU in the
  hydrogeologic unit table

Georgetown
Person
Kainer
Glen Rose
40
GeoRasters

• GeoRasters also store hydraulic properties such
  as transmissivity, conductivity, and specific
  yield

Raster of hydraulic conductivity in the Edwards
Aquifer
41
GeoVolume

• Objects for representing 3D volume objects
• Geometry is multipatch

42
GeoVolume

• Can create the volumes as a set of 3D triangles
• Not real volume cant do any 3D operations
• Volumes in this example were generated in GMS and
  imported to the geodatabase

Volumes in GMS
GeoVolumes in the geodatabase
43
Components

• Geology - Representation of data from geologic
  maps
• Wells and Boreholes Description of well
  attributes and borehole data
• Hydrostratigraphy 2D and 3D description of
  hydrostratigraphy
• Temporal Representation of time varying data
• Simulation Representation of groundwater
  simulation models (focus on MODFLOW)

44
Types of time varying datasets

• Single variable time series A single variable
  recorded at a location, such as stream discharge
  or groundwater levels
• Multi variable time series Multiple variables
  recorded simultaneously at the same location,
  such as chemical analysis of a water sample
• Time varying surfaces (raster series) Raster
  datasets indexed by time. Each rater is a
  snapshot of the environment at a certain time.
• Time varying features (feature series) A
  collection of features indexed by time. Each
  feature in a feature series represents a variable
  at a single time period.

45
Time series

• The most basic case is a monitoring device
  recording values over time (e.g. monitoring well,
  streamflow gage)

46
Time series

• TimeSeries table is the basic table for storing
  time series data
• Need to support what, where, and when
• Variables table defines variable objects

47
Time series

• By querying the table we can create different
  data views

48
Time series views create time series graph

• FeatureID of the time series HydroID of the
  spatial feature (e.g. Well)

Well HydroID 2791
49
Time series views map a variable at a given time
Map a certain variable (e.g. water levels) at a
given time (e.g. February 2004)
Feet above mean sea level
50
Multi-variable time series

• Data are indexed by space (FeatureID) and by time
  (TsTime) but instead of one variable we store
  multiple variables.
• The column heading is the variable key (VarKey)

51
Multi-variable time series

• Data are indexed by space (FeatureID) and by time
  (TsTime) but instead of one variable we store
  multiple variables.
• The column heading is the variable key (VarKey)

52
RasterSeries

• Raster datasets indexed by time
• Each raster represents a continuous surface
  describing a variable for a given time over an
  area of interest

January 1991
January 1992
January 1993
53
Feature Series

• A collection of features indexed by time (e.g.
  particle tracks)
• Features are indexed by VariableID, TsTime.
• Features can also be indexed with a GroupID. Each
  group of features creates a track over time

54
Components

• Geology - Representation of data from geologic
  maps
• Wells and Boreholes Description of well
  attributes and borehole data
• Hydrostratigraphy 2D and 3D description of
  hydrostratigraphy
• Temporal Representation of time varying data
• Simulation Representation of groundwater
  simulation models (focus on MODFLOW)

55
Representing simulation models

• Georeference model inputs and outputs (in space
  and time)
• Focus on MODFLOW, block centered finite
  difference grid (nodes are in the center of the
  cells)
• Represent 2D and 3D models

Block-centered finite difference grid
56
Simulation component
Features for representing data from simulation
models
57
Boundary
Polygon feature class for representing the extent
and orientation of a simulation model
58
Cell2D and Node
Cell2D polygon feature class that represents
cells or elements associated with a
two-dimensional simulation model or a single
layer of a three-dimensional model Node point
feature class used in combination with Cell2D to
represent the models mesh/grid.

• Finite element mesh
• Mesh centered finite difference grid
• Cell centered finite difference grid

59
Cell3D

• Multipatch feature class that represents
  three-dimensional cells and elements
• Used mostly for visualization of 3D models