Building Hydrologic Information Systems David R. Maidment Center for Research in Water Resources University of Texas at Austin Modeling

Hydrologic Information System Modeling A combination of geospatial and temporal hydrologic information which supports analysis, modeling and decision making

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

GIS data layers for Water Resources

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 and application tools are in the public domain

GIS in Water Resources Discipline “Follow a drop of water from where it falls on the land, to the stream, and all the way to the ocean.” R.M. Hirsch, USGS

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

Arc Hydro — Hydrography

Arc Hydro — Hydrology

Streams WatershedsWaterbody Hydro Points Arc Hydro Framework Input Data

Arc Hydro Framework Data Model

National Hydrography Dataset, NHD Basins Waterbody (NHD) Arc Hydro Framework For South Florida Hydro Points

Flow Time Time Series HydrographyHydro Network Channel System Drainage System Arc Hydro Components

Database Interface Model 1 Model 2 Model 3 GIS GIS Preprocessors for Hydrologic Models

Interface data models HMS RAS WRAP GIS Geo Database Arc Hydro data model Connecting Arc Hydro and Hydrologic Models

Regional Storm Water Modeling Program and Master Plan for San Antonio City of San Antonio

Modeling System Rainfall Data: Rain gages Nexrad Calibration Data: Flows Water Quality Geospatial Data: City, County SARA, other Floodplain Management Integrated Regional Water Resources planning Capital Improvement Planning Flood Forecasting Water quality planning San Antonio Regional Watershed Modeling System “Bring the models together”

Regional Watershed Modeling System Case Study Rosillo Creek watershed Arc Hydro Geodatabase for whole watershed HEC-HMS hydrology model for whole watershed HEC-RAS hydraulic model for Rosillo Creek Salado Creek watershed Components: Bexar County

Arc Hydro and HEC-HMS Arc Hydro Schematic Network HEC-HMS Hydrologic Model Calculates Flows

Arc Hydro and HEC-RAS Arc Hydro Channel Cross Sections HEC-RAS Hydraulic Model Calculates Water Surface Elevations

Flow Change Points Models communicate with one another through Arc Hydro at designated points

Nexrad Map to Flood Map in Arc 9 Model Builder FLO ODP LAIN MAP Flood map as output Model for flood flow Model for flood depth HMS Nexrad rainfall map as input

Fecal Coliform in Galveston Bay (Monthly data, ) Coliform Units per 100 ml Tracking Analyst Demo

Demos of Model Builder and Tracking Analyst

Water Availability 1996 Texas drought –Governor Bush asks “how much water do we have? How much are we using? How much do we need?” -- Ooops. No good answers! 1997 Senate Bill 1 passed by Legislature –Regionalizes water planning in Texas and establishes surface water availability modeling 2001 Senate Bill 2 passed by Legislature –Establishes groundwater availability modeling and initiates instream flow assessment

Improvements from Senate Bill 1: Water Modeling and Planning Before Senate Bill 1, water planning was done state-wide by TWDB SB1 established 14 water planning regional groups, who are now responsible for planning water supply in their area Water Availability Modeling (TNRCC)

Improvements from Senate Bill 1: Digital Map of Texas: 100K → 24K 1° 7.5' 7.5' Quadrangles 1:24,000 scale 4400 maps cover Texas 1° Quadrangles 1:100,000 scale Approx. 100 maps cover Texas

Improvements from Senate Bill 1: Water Availability Modeling Rio Grande Colorado Brazos Sulphur Trinity Nueces City of Austin 8000 water right locations 23 main river basins Inform every permit holder of the degree of reliability of their withdrawal during drought conditions (TCEQ)

CRWR Mission for Senate Bill 1 CRWR (UT Austin) aids in the response to Senate Bill 1 by providing to TNRCC watershed parameters defined from geospatial data for each water right location These data are input by TCEQ contractors to a Water Rights Assessment Package (developed at TAMU) which determines the % chance that the water will actually be available at that location TCEQ sends the owner of the water right a letter specifying the availability of water

Water Rights in the Sulphur Basin Water right location Stream gage location Drainage areas delineated from Digital Elevation Models are used to estimate flow at water right locations based on flow at stream gage locations

Digital Elevation Model

Topographic Map of West Austin 1:24,000 scale Hog Pen Ck 4 km

Digital Elevation Model (DEM) Contours

Austin West 30 Meter DEM

Cell Size 30m100m

Eight Direction Pour Point Model Water flows in the direction of steepest descent

Flow Direction Grid

Cell to Cell Grid Network Through the Landscape Stream cell

Streams and Watersheds Defined from the DEM

Comparison of Drainage Areas DEM USGS Difference is ~ 0.5%

Watershed Properties Averaged over the Drainage Area Property grid (CN or Precipitation) Drainage Areas +

Connectivity of the Control Points Neches Basin This flow order is used in the Water Rights Analysis Package

Data Products GIS coverages for determining watershed parameters Watershed parameters as input for WRAP model = Analysis completed for more than 10,000 locations in all river basins of Texas

Improvements from Senate Bill 2: Instream Flow requirements Requires TPWD, TWDB, TCEQ to develop procedures for defining instream flow requirements Implemented on priority study regions by 2010 Based on fish habitat analysis Priority Study Regions Guadalupe San Antonio Brazos Trinity Sabine

Process Flowchart Instream Flow Decision Making Hydrodynamic Model Habitat Descriptions Habitat Model ArcGIS SMS/RMA2Data Collection and some statistics Depth & velocity Species groups Criterion

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

Depth Sounder (Echo Sounder) 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.

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

Measurement System GPS Antenna Depth Sounder Computer and power setup

Channel Bed Soundings

Bathymetry from Side-Scanning Sonar Channel demo

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

NSIP Sites

NSIP River Basin Outflow Sites Metric: Operate streamgaging stations near the terminus of each of the 352 Hydrologic Accounting Units Coverage Model: Sites associated with drainage areas

Guadalupe basin The river network contains gages (As hydro junctions) and junctions which are not gaged (Network Junctions) 29 USGS gages in the database collecting information between 1905 and 2000

How does the model work? – Step 1 Junction 161 (ungaged location) is selected for interpolation Select a location for predicting discharge

How does the model work? – Step 2 Trace downstream to find the next down stream gage Trace downstream from junction 161

Geospatial Interpolation of Streamflow Upstream Location Downstream Gage