Arc Hydro Groundwater Data Model

GIS in Water ResourcesFall 2009

With contributions from Norm Jones (BYU), Gil Strassberg (Aquaveo), David Maidment (UT Austin), Tim Whiteaker (UT Austin), Steve Grise (ESRI), Steve Kopp (ESRI)

Learning Objectives:By the end of this class you should be able to:

• Understand how we describe subsurface features in GIS using the Arc Hydro Groundwater Data Model

• Understand the linkages from one subsurface feature to another, and to time series or hydrostratigraphic data

Outline

• Background

• Arc Hydro Framework

• Arc Hydro Groundwater Components

Linking GIS and Water Resources

GISWaterResources

Arc Hydro: GIS for Water Resources

• Arc Hydro– An ArcGIS data model

for water resources– Arc Hydro toolset for

implementation– Framework for linking

hydrologic simulation models

The Arc Hydro data model andapplication tools are in the publicdomain

Published in 2002, now in revision for Arc Hydro IIPublished in 2002, now in revision for Arc Hydro II

Challenges in developing Arc Hydro• ArcGIS is a very successful static, 2D or 2.5D system• For surface water resources we need

– Close connection between raster terrain and vector stream data

– Linkage to time varying water data observations stored at gages

– Access to precipitation and evaporation data “fields”• For groundwater resources we need

– 3D representation of boreholes and hydrogeologic units– Integration with groundwater models, especially

MODFLOW, which has become the ArcInfo of groundwater

Arc Hydro Groundwater – Time Line

• Arc Hydro book and tools published - 2002

• Initial groundwater data model discussions, initial designs at the Center

for Research in Water Resources, UT Austin - 2003

• First complete design of Arc Hydro Groundwater data model - 2006

• Arc Hydro Groundwater presented at ESRI User Conference - 2007

• ESRI and Aquaveo team to develop Arc Hydro Groundwater Tools - 2007

• Arc Hydro Groundwater Tools released - 2009

• Arc Hydro Groundwater book - 2009-2010

What is a hydrologic data modelBooch et al. defined a model: “a simplification of reality created to Booch et al. defined a model: “a simplification of reality created to

better understand the system being created”better understand the system being created”

ObjectsObjects

AquiferAquifer

StreamStream

WellWell

VolumeVolumeR.M. Hirsch, USGS

Developing a groundwater data modelTake a variety of spatial information and integrate into one Take a variety of spatial information and integrate into one

geospatial database with a common terminologygeospatial database with a common terminology

• Better communicationBetter communication• Integration of data Integration of data • Base for applicationsBase for applications

Framework and Components

Network

Framework

Surface water componentsSurface water components

Drainage

Hydrography

Channel

Groundwater componentsGroundwater components

Components can be added to the framework to represent Components can be added to the framework to represent

specific themes in more detailspecific themes in more detail

Borehole data

Hydrostratigraphy

Geology

SimulationTemporal (enhanced)

Arc Hydro Framework• Basic representation of surface water and groundwater Basic representation of surface water and groundwater • Components can be added to the framework to represent Components can be added to the framework to represent

specific themes in more detailspecific themes in more detail

Well• Wells are the most basic features in groundwater databases• Attributes of wells describe the location, depth, water use,

owner, etc.

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

Point datasetWell

HydroIDHydroCodeLandElevWellDepthAquiferIDAqCodeHGUIDFType

Wells in the Edwards AquiferWells in the Edwards Aquifer

Aquifer features• Polygon features for representing aquifer boundaries and Polygon features for representing aquifer boundaries and

zones within themzones within them

• Representation of Aquifer mapsRepresentation of Aquifer maps

Aquifer features

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

Hydro Features • Key attributes for feature identificationKey attributes for feature identification

• HydroID – Unique ID within the geodatabase (internal relationships)HydroID – Unique ID within the geodatabase (internal relationships)

• HydroCode – Public identifier (external relationships)HydroCode – Public identifier (external relationships)

HydroID• A new ID assigned to features in a Arc Hydro geodatabase

• Uniquely identifies features within 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

HydroCode links to external applications• Web interface for groundwater data in TexasWeb interface for groundwater data in Texas• Texas Water Information Integration & Dissemination (WIID)Texas Water Information Integration & Dissemination (WIID)

Aquifer and well

• Well features are related to Aquifers: The Well features are related to Aquifers: The AquiferIDAquiferID of a well feature is of a well feature is

equal to the equal to the HydroIDHydroID of an aquifer feature of an aquifer feature

• An aquifer can be associated with one or more wells (1:M An aquifer can be associated with one or more wells (1:M

relationship)relationship)

• Can take a different approach to support M:N relationshipCan take a different approach to support M:N relationship

*

HydroIDHydroCodeNameHGUIDFType

Aquifer

HydroIDHydroCodeLandElevWellDepthAquiferIDAqCodeHGUIDFType

Well

1

Aquifer and well

Well HydroID = 53

Wells and TimeSeriesWellWell features are related with time series (water features are related with time series (water levels, water levels, water qualityquality))

San Marcos springs Springs

Sink Creek

San Marcos

Monitoring Well (295443097554201)

MonitoringPoint has time seriesMonitoring points are related with time series (streamflow, water quality, precipitation)

Integration of surface water and groundwater data

Streamflow Gage at Comal Springs, New

Braunfels Texas

Well in the Edwards Aquifer)

The common framework supports analysis of surface water and groundwater data together

Surface water - groundwater linkageRelationships between surface water and aquifer enable analysis based on spatial and hydrologic relationships

Streams over the outcrop = recharge features

Implementing the Arc Hydro framework

1.1. CreateCreate the classes of the Arc Hydro Framework (manually the classes of the Arc Hydro Framework (manually

using ArcCatalog or by importing from an xml schema)using ArcCatalog or by importing from an xml schema)

2.2. AddAdd project specific classes, attributes, relationships, and project specific classes, attributes, relationships, and

domains as necessary domains as necessary

3.3. DocumentDocument datasets and changes made to the data model datasets and changes made to the data model

4.4. ImportImport data into the framework classes (e.g. streams, wells, data into the framework classes (e.g. streams, wells,

aquifers, time series)aquifers, time series)

5.5. AssignAssign key attributes to uniquely identify the features and key attributes to uniquely identify the features and

establish relationshipsestablish relationships

6.6. ApplyApply tools to create new features and calculate attributes tools to create new features and calculate attributes

7.7. VisualizeVisualize data and data and createcreate products (maps, scenes, reports) products (maps, scenes, reports)

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)

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

• Groundwater features are closely tied to geologyGroundwater features are closely tied to geology

• Geologic maps vary in scale (continental, regional, local)Geologic maps vary in scale (continental, regional, local)

• Provide a simple data structure to support mappingProvide a simple data structure to support mapping

GeologyGeology AquifersAquifers

Maps from the United States National Atlas (http://nationalatlas.gov/).

Geologic map databases

Arc Geology: Arc Geology: generic geologic map data model implemented within

ArcGIS (figure from Raines et al. 2007)

Geodatabase design for storing data from Geodatabase design for storing data from the Geologic Atlas of Texas the Geologic Atlas of Texas ((

http://www.tnris.org/news.aspx?id=244http://www.tnris.org/news.aspx?id=244)

Geology component

Map modified from: Geologic map of the Edwards Aquifer recharge zone, south-central Texas. U.S. Geological Survey SIM 2873

GeologyPoint

GeologyLine GeologyArea

GeologyLine

HydroIDHydroCodeGeoAbbrevDescriptionHGUIDHGUCodeFTyp

GeologyArea

HydroIDHydroCodeGeoAbbrevDescriptionHGUIDHGUCodeFTyp

GeologyPoint

HydroIDHydroCodeGeoAbbrevDescriptionHGUIDHGUCodeFType

GeologyPoint: Point feature (e.g. springs, caves, sinks, and observation points)

GeologyLine: Line features (e.g. faults, contacts)

GeologyArea: Areal features (e.g. rock units and alteration zones)

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)

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

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

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 Point datasetWell

HydroIDHydroCodeLandElevWellDepthAquiferIDAqCodeHGUIDFType

Wells in the Edwards AquiferWells in the Edwards Aquifer

Borehole data• 3D data (screens, completion intervals, stratigraphy) are referenced 3D data (screens, completion intervals, stratigraphy) are referenced

along the wellalong the well

• From depth (top) – To depth (bottom)From depth (top) – To depth (bottom)

BoreholeLog table• Used to store Used to store 3D borehole 3D borehole data related with well featuresdata related with well features

• Each row in the table represents a Each row in the table represents a point/intervalpoint/interval along a borehole along a borehole

• Data are related with a Well feature through the Data are related with a Well feature through the WellIDWellID attribute attribute

• 3D geometry is defined by the 3D geometry is defined by the TopElev and BottomElev TopElev and BottomElev attributesattributes

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, samples)• BoreLine is a 3D line feature class for representing intervals along a

borehole

BorePoint

BoreLine

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)

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

Georgetown Fm. (GTOWN)

Cyclic + Marine member (CYMRN)

Upper confining unit

Leached + collapsed member (LCCLP)

Regional dense member (RGDNS)

Grainstone member (GRNSTN)

Kirschberg evaporite member (KSCH)

Dolomitic member (DOLO)

Upper Glen Rose (UGLRS)

Stratigraphic units Hydrogeologic units

Pearson Fm.

Basal Nodular member (BSNOD)

Kainer Fm.

Georgetown Fm.

Ed

war

ds

A

qu

ifer

Hydrogeologic unit table• HydroGeologicUnit table provides a conceptual

description of hydrogeologic units• Hydrogeologic units can be attributed 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

Representations of hydrogeologic units• Different spatial representations of hydrogeologic units with 2D and 3D

objects• Workflow for creating 3D hydrogeologic models

Cross sections/Fence diagrams

Volume objects representing hydrogeologic units

Cross sections derived from the solid model

Define hydrogeologic units along boreholes

Create surfaces from borehole data and

cross sections

Interpolate and edit cross sections

“Cut” cross sections from the solid model

Surfaces defining the extent of hydrogeologic units

Borehole Stratigraphy

Build volumes between surfaces

Create cross sections based on the surfaces

Hydrogeologic unit table• Hydrogeologic units are described with different spatial instances

(outcrops, borehole intervals, surfaces, cross sections, and volumes)• HGUID is the key attribute

HGUID

HGUID

Conceptual description

Spatial description

GeoAreaPolygon feature class

HydrogeologicUnitTable

SectionLinePointZ feature class

GeoRastersRaster dataset

GeoSectionMultipatch feature class

GeoVolumeMultipatch feature class

1

*

GeoArea

GeoArea feature representing the Kainer hydrogeologic unit

GeologyArea features represent data from geologic

mapsGeologyArea

• 2D polygons defining boundaries of hydrogeologic units2D polygons defining boundaries of hydrogeologic units• GeoArea (conceptual/interpolated boundary) ≠ GeologyArea (mapped GeoArea (conceptual/interpolated boundary) ≠ GeologyArea (mapped

outcrop)outcrop)

Data points representing top elevations of the Kainer formation

Representation of Cross Sections• SectionLineSectionLine defines the 2D cross section

• GeoSectionGeoSection represent 3D sections as 3D features represent 3D sections as 3D features

• SectionIDSectionID of the polygon relates back to the section line of the polygon relates back to the section line

A

A’B B’

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

Glen Rose

Kainer

Person

GeoRasters• GeoRasters also store hydraulic properties such

as transmissivity, conductivity, and specific yield

K (feet/day)

Raster of hydraulic conductivity in the Edwards AquiferRaster of hydraulic conductivity in the Edwards Aquifer

GeoVolume• Objects for representing 3D volume objects• Geometry is multipatch - Can create the volumes as a set of 3D

triangles• Not real volume – can’t do any 3D operations

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)

Types of time varying datasets• Single variable time series (time series) – A single

variable recorded at a location, such as stream discharge or groundwater levels

• Multi-variable time series (attribute 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.

Time series • The most basic case is a monitoring device recording

values over time (e.g. monitoring well, streamflow gage)

San Marcos springs Springs

San M

arco

s Riv

er

Sink Creek

San Marcos

Monitoring Well (295443097554201 )

Time series • TimeSeries table is the basic table for storing time series data• Need to support: what, where, and when • VariableDefinition table describes variables

Time (TsTime)

Space (FeatureID)

Variables (VarID)

Time series • By querying the table we can create different data views

2791

TsTime

FeatureID

VarID

2FeatureID

VarID

2791 FeatureID

VarID

2

(a) (b) (c)TsTime TsTime

Time series views – create time series graph

Well HydroID = 2791

• FeatureIDFeatureID of the time series = of the time series = HydroIDHydroID of the spatial feature (e.g. Well)of the spatial feature (e.g. Well)

Time series views – map a variable at a given timeMap a certain variable (e.g. water levels) at a given time (e.g. Map a certain variable (e.g. water levels) at a given time (e.g. February 2004)February 2004)

FeatureID

VarID

2

TsTime

2/2004 Feet above mean sea level

Multi-variable time series• Data are indexed by space (FeatureID) and by time (TsTime) but Data are indexed by space (FeatureID) and by time (TsTime) but

instead of one variable we store instead of one variable we store multiple variablesmultiple variables..

• The column heading is the The column heading is the variable key (VarKey)variable key (VarKey)

Variables (VarKey)

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

Feature Series• A collection of features indexed by time (e.g. particle tracks)• Features are indexed by VarID, TsTime.• Features can also be indexed with a GroupID. Each group of

features creates a track over time

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)

Representing simulation models• GeoreferenceGeoreference model inputs and outputs (in space and time) model inputs and outputs (in space and time)

• Focus on Focus on MODFLOWMODFLOW, block centered finite difference grid (nodes are in , block centered finite difference grid (nodes are in the center of the cells)the center of the cells)

• Represent Represent 2D2D and and 3D3D models models

Block-centered finite difference grid

Simulation component

Features for representing data from simulation modelsFeatures for representing data from simulation models

BoundaryPolygon feature class for representing the extent and Polygon feature class for representing the extent and orientation of a simulation modelorientation of a simulation model

Cell2D and Node Cell2D: polygon feature class that represents cells or elements Cell2D: polygon feature class that represents cells or elements associated with a two-dimensional simulation model or a single associated with a two-dimensional simulation model or a single layer of a three-dimensional modellayer of a three-dimensional model

Node: point feature class used in combination with Cell2D to Node: point feature class used in combination with Cell2D to represent the model’s mesh/grid. represent the model’s mesh/grid.

Node Features Cell2D Features

(a) (b) (c)

a) Finite element mesh

b) Mesh centered finite difference grid

c) Cell centered finite difference grid

Cell2D and Node Used to create maps of model dataUsed to create maps of model data

Node3D and Cell3D• Node3D – a Z enabled point feature class

• Cell3D - Multipatch feature class

• Represent three-dimensional cells and Nodes

• Used mostly for Used mostly for visualization of 3D modelsvisualization of 3D models

Summary Concepts• Arc Hydro Groundwater…

– extends Arc Hydro to represent groundwater datasets in GIS

– includes components for aquifers, wells, hydrogeologic features, time series, and simulation model output

– links features to hydrogeologic layers via HGUID, and to aquifers via AquiferID

Websites• ESRI Data Model Website: www.esri.com/datamodels

• Arc Hydro Groundwater Websites: www.archydrogw.comwww.aquaveo.com/archydro

Contact:•Norm Jones (njones@aquaveo.com)

•Gil Strassberg (gstrassberg@aquaveo.com)

•Steve Grisé (sgrise@esri.com)