Why should the Corps of Engineers be interested in Arc Hydro? –Watershed planning –Reservoir operations –Flood damage reduction –Ecosystem restoration Arc Hydro: GIS for Water Resources David R. Maidment, University of Texas at Austin

Hydrologic Information System Hydrologic Modeling Arc Hydro Geodatabase

1996 Texas Drought George W. Bush, (then Governor of Texas) asked: “Tell me how much water we have, how much water we’re using and how much water we need” State water officials did not have adequate answers

Texas 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

Hydrologic Cataloging Units (HUCS) Guadalupe Basin (4 HUC’s) H ydrologic U nit C ode = HUC’s cover continental US average area ~ 1 county

Water Availability in the Guadalupe Basin Stream Gauge (14) Water Diversion (440) Estimate water availability at each legally permitted water diversion point based on “naturalized” flow at stream gages and the effects of other permitted diversions

Digital Elevation Model National Elevation Dataset 30m x 30m cells 11,000,000 cells to cover San Marcos basin 70,000,000 cells to cover Guadalupe basin San Marcos basin

Drainage Area Delineated from the Digital Elevation Model Arc Hydro attribute DrainArea

Estimating Naturalized Flow at Diversion Points QdQd QfQf AdAd AfAf Q d = Q f AdAfAdAf Naturalized flow record at stream gage (50 years of monthly flows) Estimated flow record at diversion point

Length Downstream D F Flow distance (D to F) = Length Downstream (D) – Length Downstream (F) Length Downstream (D) Length Downstream (F) F D Arc Hydro attribute LengthDown Seepage losses

Water Availability Modeling Hydrologic Modeling Water Rights Analysis Package (WRAP) 50 year series of naturalized monthly flows at stream gages GIS data for each diversion point Letter to each water permit owner specifying % of permitted flow available during a drought Completed for ~ 10,000 water permit holders,

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 Texas Natural Resources Conservation Commission Hydrologic modeling by engineering consultants Water Availability Assessment (completed for ~ 10,000 permit holders, )

Accomplishments Arc Hydro data model design completed and published on web ( Arc Hydro book in production at ESRI Press Arc Hydro toolset v. 1.0 in beta testing

CD-ROM at back of book Arc Hydro UML diagrams, Repository, Example Geodatabases, Toolset, Tutorials

Arc Hydro Toolset Ver 1.0 Provides tools for processing raster and vector data and populating the attributes of the Arc Hydro data model

GIS in Water Resources Consortium Bringing together these two communities by using a common geospatial data model GIS CRWR Water Resources

Flow Time Time Series Hydro FeaturesHydro Network Channel System Drainage System ArcGIS 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

Streams WatershedsWaterbody HydroPoints Arc Hydro Framework Input Data

Arc Hydro Framework

Arc Hydro Framework Dataset for the Guadalupe Basin

HydroNetwork through Canyon Lake Generic Junction (for topological connection of edges) Flowlines through water body

HydroJunction has Waterbody Relationship

Scales of representation of Drainage Systems Basins – drainage areas for water resources management Catchments – subdivision of Basin into elementary drainage areas by physical rules Digital Elevation Model – land surface terrain grid cells Watersheds – subdivision of Basin for a particular hydrologic purpose

NWS forecast Watersheds (flooding) EPA TMDL Segments (water quality) TNRCC water availability points (water supply) Guadalupe HydroNetwork Watersheds of the Guadalupe Basin

Catchments, DrainageLines and DrainagePoints

EDNA – Elevation Derivatives for National Application

Catchments Subdivided at Watershed Outlet

Regional Analysis HydroNetwork to provide connectivity of flow through large regions Digital elevation model for terrain analysis within basins

Michael Schultz NWS River Forecast Center Fort Worth, Texas 1998 Guadalupe Flood

Cross-Sections developed using HEC-GeoRAS and National Elevation Dataset

Hydrologic simulation Using NWS Fldwav model

Guadalupe Network Study area only 1.4 km!

1/2 meter Digital Ortho Photography Study Area (Guadalupe river near Seguin, TX)

Boat setup for data collection

Accoustic Doppler Current Profiler Provides full profiles of water velocity and direction in the ocean, rivers, and lakes. Also used for discharge, scour and river bed topography.

The electronic depth sounder operates in a similar way to radar It sends out an electronic pulse which echoes back from the bed. The echo is timed electronically and transposed into a reading of the depth of water. Depth Sounder (Echo Sounder)

Differential GPS: Bank to Boat GPS gives the location of each point collected in terms of latitude and longitude. Two locations for differential GPS.

Channel Data Each point has (x,y,z)

Interpolation Points are interpolated in ArcMap to produce a continuous surface.

FishNet (2D) FishNet is generated in ArcMap using FishNet tool in ArcGIS.

3D Visualization in ArcScene

Centerline Define the centerline such that it joins the center of flow (area) at each cross section.

Measure in ArcGIS A PolylineM can store m-values at each vertex along with x and y coordinates. Measures are assigned in meters

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.

Coordinate Transformation Sinuous river Profile line and cross-sections Straightened river

Straightened River in 3D

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!

National Water Information System Web access to USGS water resources data in real time

Space Historical daily mean discharge Streamflow statistics Real Time data Streamflow Information in Space and Time Time At Gages Anywhere on a Stream Future PossibilitiesCurrent Streamstats

TSDateTime FeatureID TSType TSValue Arc Hydro Time Series Object

View 1: Time Series for a Spatial Feature TSDateTime FeatureID TSType 101

View 2: Time Series of a Particular Type TSDateTime FeatureID TSType Evaporation

View 3: Time Series of a Particular Type for a Single Feature TSDateTime FeatureID TSType Evaporation

HRAP Cells for Nexrad Data Average area = 14.5 km 2

Water Balance in the Landscape Atmospheric Water Soil WaterSurface Water Groundwater Precipitation Evaporation Runoff Recharge Baseflow

National Hydro Data Programs National Elevation Dataset (NED) National Hydrography Dataset (NHD) Watershed Boundary DatasetElevation Derivatives for National Application (EDNA)

EDNA Catchments Average area = 7.5 km 2

Modflow Groundwater Cells Average area = 2.6 km 2 Modflow Model of the Edwards-Trinity aquifer

Intersection of Nexrad and Catchments Atmospheric Water Soil Water Surface Water Surface Water Balance

Intersection of Nexrad and Modflow Cells Atmospheric Water Groundwater Balance

Intersection of Nexrad, Catchments and Modflow Atmospheric Water Soil WaterSurface Water Groundwater

Coupling Spatial and Temporal Data 1 hour Nexard Rainfall on the Guadalupe Basin October 13, 2001

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

Dynamic Linked Library Can have Fortran subroutines in a DLL Muskingum flow routing

Independent Hydrologic Model VB progam reads and writes text files

Analysis, Modeling, Decision Making Arc Hydro Geodatabase Visual Basic ArcGIS Relational Database (Access) Excel Interfaces to Arc Hydro Data and Models

Other Arc Hydro Implementations USGS –Stream Stats HEC –GeoRAS –GeoHMS Streamstats

Why should the Corps of Engineers be interested in Arc Hydro? –Watershed planning –Reservoir operations –Flood damage reduction –Ecosystem restoration Arc Hydro: GIS for Water Resources David R. Maidment, University of Texas at Austin