Role of the Texas Water Development Board in Environmental Flow studies

1
Role of the Texas Water Development Board in
Environmental Flow studies

• Barney Austin
• Surface Water Resources Division
• Texas Water Development Board
• May 21, 2004

2
TWDB Offices

• Office of Finance
• Office of Project Finance Construction
• Resource Information Office
• Office of Planning (Bill Mullican)
• Water Resource Planning
• Conservation
• Groundwater Resources
• Surface Water Resources
• Instream Flows
• Bays and estuaries

3
Role of TWDB in Bays Estuaries studies

• Funding
• Research Planning Fund 417,046 per year for
  Environmental studies (data, model enhancement,
  research and reviews)
  
• Data collection Partly collected by TWDB staff,
  also through grants (e.g. TCOON Tide gages, USGS
  streamgages)

4
Role of TWDB in Bays Estuaries studies

• Hydrology data collection
• Estimating the total surface water inflow to our
  bays and estuaries
  
• Rainfall, evaporation, gaged flow, ungaged flow
• Watershed delineation
• TxRR Rainfall-Runoff model
• Salinity and tide data compilation, analysis.

5
Role of TWDB in Bays Estuaries studies

• Optimization
• TxEMP (Texas Estuarine Mathematical Programming
  model)
  
• Inflow-Harvest (or catch) statistical regression
  equations for individual species
  
• Development of total Harvest vs. Inflow curve for
  the bay, including appropriate constraints
  
• Objective framework for balancing competing
  demands
  

6
Role of TWDB in Bays Estuaries studies

• Nutrient balance
• Study and quantification of level of nutrients
  required to maintain the health of the bay
  
• Provides further validation of the optimization
  results

7
Role of TWDB in Bays Estuaries studies

• Hydrodynamic modeling
• TxBLEND
• 2-D, finite element model for determining
  distribution and concentration of salt across the
  bay
  
• Calibrated using long-term salinity measurements
  and intensive survey data
  
• Used for TPWD verification of needs analysis and
  nutrient balance work
  
• TxBLEND used for other applications

8
Role of TWDB in Instream Flow studies

• Funding
• Research Planning Fund (share 417,046 per year
  for environmental studies
  
• Reconnaissance and data gathering contracts
  with
  
• San Antonio River Authority
• Lower Sabine River Authority
• Brazos River Authority
• Administered by the TPWD
• Principally for biological data collection

9
Role of TWDB in Instream Flow studies
10
Summary

• More technical detail in later presentations
• Stakeholder participation and contribution
  crucial to complete legislative mandates
  
• Funding
• Acceptance of results
• Look forward to receiving guidance from the
  legislative committees