In cooperation with the Texas Water   Development Board

**Evaluation of the   Streamflow-Gaging Network   of Texas and a Proposed Core Network**

By Raymond M. Slade, Jr., Teresa   Howard, and Roberto Anaya

U.S. Geological Survey   Water-Resources Investigations Report 01–4155

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pdf (1.64 MB)

plate (7.48 MB, 26" X 26")

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**Contents**

Abstract 

Introduction 

Background 

Purpose and Scope 

Streamflow Network Analysis 

History of Streamflow Gaging in Texas 

Network Evaluations in Texas 

Network Funding and Data Uses 

Major Objectives of a Core Network 

Evaluation of the Existing Network 

Hydrologic Regions 

Regional Optimization Model 

Flow Correlation 

Proposed Core Network 

Summary 

References 

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Plate

| 1.  | Map showing locations of stations in the proposed core streamflow network       of Texas |
|----------|------------------------------------------------------------------------------------------|

**Figures**

| 1.            | Graph showing number of daily mean and annual peak streamflow       stations in Texas, 1898–1996                     |
|--------------------|----------------------------------------------------------------------------------------------------------------------------|
| 2.            | Map showing locations of active and discontinued daily streamflow       stations, October 1, 1998                          |
| 3.            | Map showing hydrologic regions and major basins of Texas                                                                   |
| 4–9.    | Graphs showing relation between mean sampling error, number       of streamflow-gaging stations, and planning horizon for: |
|                    | 4.                                                                                                                    | Mean annual streamflow in hydrologic regions 1–4 |
|                    | 5.                                                                                                                    | Mean annual streamflow in hydrologic regions 5–8 |
|                    | 6.                                                                                                                    | Mean annual streamflow in hydrologic regions 9–11 |
|                    | 7.                                                                                                                    | 25-year peak streamflow in hydrologic regions 1–4 |
|                    | 8.                                                                                                                    | 25-year peak streamflow in hydrologic regions 5–8 |
|                    | 9.                                                                                                                    | 25-year peak streamflow in hydrologic regions 9–11 |
| 10–11.  | Maps showing correlation of annual mean streamflow between       paired streamflow-gaging stations in:                     |
|                    | 10.                                                                                                                   | North Texas |
|                    | 11.                                                                                                                   | South Texas |
| 12–13.  | Maps showing correlation of annual peak streamflow between       paired streamflow-gaging stations in:                     |
|                    | 12.                                                                                                                   | North Texas |
|                    | 13.                                                                                                                   | South Texas |

**Tables**

| 1.  | Correlation coefficients of annual mean streamflows for paired       stations in north Texas basins |
|----------|-----------------------------------------------------------------------------------------------------|
| 2.  | Correlation coefficients of annual mean streamflows for paired stations       in south Texas basins |
| 3.  | Correlation coefficients of annual peak streamflows for paired stations       in north Texas basins |
| 4.  | Correlation coefficients of annual peak streamflows for paired stations       in south Texas basins |
| 5.  | Core network of streamflow-gaging stations in Texas                                                 |

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