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Namjeong Choi, PhD

Namjeong is a Hydrologist working for the Integrated Hydrology and Data Science Branch of the Oklahoma-Texas Water Science Center at Fort Worth, TX.

With her experience in environmental hydraulics and urban hydrology, she focuses on addressing various local and regional water resources challenges and providing actionable science for cooperators and the public. Her recent studies include surface water modeling, flood-inundation mapping, water budget analysis, continuous water quality data analysis, and statistical discharge estimation, using skills in hydrologic/hydraulic modeling software, GIS, Python, and R.

Education and Certifications

  • Ph.D. University of Illinois at Urbana-Champaign, Urbana, IL 2016

Science and Products

Flood waters carry large logs and inundate the base of trees

Identifying Opportunities to Strengthen Climate Resilience in Flood-Prone Urban Communities in Harris County, Texas

Project Overview Flooding in urban centers caused by increasingly severe storms has led to massive economic, social, and ecological damage. Researchers supported by this South Central CASC project will examine flood vulnerability and mitigation efforts in Harris County, Texas, currently home to the highest concentration of federally funded relocation projects in the country. The...
By
Climate Adaptation Science Centers
Identifying Opportunities to Strengthen Climate Resilience in Flood-Prone Urban Communities in Harris County, Texas

Identifying Opportunities to Strengthen Climate Resilience in Flood-Prone Urban Communities in Harris County, Texas

Project Overview Flooding in urban centers caused by increasingly severe storms has led to massive economic, social, and ecological damage. Researchers supported by this South Central CASC project will examine flood vulnerability and mitigation efforts in Harris County, Texas, currently home to the highest concentration of federally funded relocation projects in the country. The resulting flood
Learn More

Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934–2024 Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934–2024

The Edwards aquifer in south-central Texas is one of the most permeable and productive aquifers in the United States and is the major source of public water supply for Bexar, Comal, Hays, Medina, and Uvalde Counties. The Edwards aquifer also supplies large quantities of water for use in agriculture, business, and industry in the region. The major artesian springs of the Edwards aquifer...
By
Oklahoma-Texas Water Science Center

Datasets and R Scripts Used for the Water-Budget Analysis of the Medina and Diversion Lake System, Bandera, Bexar, and Medina Counties, Texas, 1955–2022 Datasets and R Scripts Used for the Water-Budget Analysis of the Medina and Diversion Lake System, Bandera, Bexar, and Medina Counties, Texas, 1955–2022

The U.S. Geological Survey—in cooperation with the San Antonio Water System and the Edwards Aquifer Authority—used data collected during four different periods (March 1955–August 1964, October 1995–September 1996, March 2001–June 2002, and March 2017–October 2022) as part of a new study to refine previously derived relations between the altitude of the water surface of Medina Lake and...
By
Oklahoma-Texas Water Science Center

Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934–2022 Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934–2022

The Edwards aquifer in south-central Texas is one of the most permeable and productive aquifers in the United States and is the major source of public water supply for Bexar, Comal, Hays, Medina, and Uvalde Counties. The Edwards aquifer also supplies large quantities of water for use in agriculture, business, and industry in the region. The major artesian springs of the Edwards aquifer...
By
Oklahoma-Texas Water Science Center

Geospatial and model dataset for flood-Inundation maps in a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021 Geospatial and model dataset for flood-Inundation maps in a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021

This data release documents the digital data used to produce flood-inundation maps for a range of gage heights (stages) for the Sabinal River near Utopia, Tex. The simulated flood-inundation maps correspond to a range in stage from 11 to 28 feet (ft) at U.S. Geological Survey (USGS) streamgage 08197970 Sabinal River at Utopia, Tex. at intervals of 0.5-ft. The maps were created for a 10...
By
Oklahoma-Texas Water Science Center

Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934 - 2020 Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934 - 2020

The Edwards aquifer in south-central Texas is one of the most permeable and productive aquifers in the United States and is the major source of public water supply for Bexar, Comal, Hays, Medina, and Uvalde Counties. The Edwards aquifer also supplies large quantities of water to agriculture, business, and industry in the region. The major artesian springs of the Edwards aquifer provide...
By
Oklahoma-Texas Water Science Center

Water-budget analysis of the Medina and Diversion Lake system, with estimated recharge to the Edwards aquifer and the upper zone of the Trinity aquifer, Bandera, Bexar, and Medina Counties, Texas, 1955–2022 Water-budget analysis of the Medina and Diversion Lake system, with estimated recharge to the Edwards aquifer and the upper zone of the Trinity aquifer, Bandera, Bexar, and Medina Counties, Texas, 1955–2022

The U.S. Geological Survey—in cooperation with the San Antonio Water System and the Edwards Aquifer Authority—used data collected during four different periods (March 1955–August 1964, October 1995–September 1996, March 2001–June 2002, and March 2017–October 2022) as part of a new study to refine previously derived relations between the altitude of the water surface of Medina Lake and...
Authors
Richard Slattery, Namjeong Choi, Allan K. Clark
By
Oklahoma-Texas Water Science Center

Component 1: Data and monitoring gap analysis Component 1: Data and monitoring gap analysis

The goal of Component 1 is to identify available data and data gaps in the Texas coastal region and to establish a plan for obtaining data critical for successful coastal flood analysis in these regions. This component is supporting the expansion and improvement of data observations for inland, coastal, and ocean systems.
Authors
David Wallace, Glenn Harwell, Namjeong Choi
By
Oklahoma-Texas Water Science Center

Flood-inundation maps created using a synthetic rating curve for a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021 Flood-inundation maps created using a synthetic rating curve for a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021

In 2021, the U.S. Geological Survey (USGS), in cooperation with the Bandera County River Authority and Groundwater District and the Texas Water Development Board, studied floods to produce a library of flood-inundation maps for the Sabinal River near Utopia, Texas. Digital flood-inundation maps were created for a 10-mile reach of the Sabinal River from USGS streamgage 08197936 Sabinal...
Authors
Namjeong Choi
By
Oklahoma-Texas Water Science Center

Flood warning toolset for the Sabinal River near Utopia, Texas Flood warning toolset for the Sabinal River near Utopia, Texas

Introduction Floods are one of the most frequent and expensive natural disasters that occur across the United States. Rapid, high-water events that occur in local areas—flash floods—are especially difficult for emergency managers to predict and provide advance warning to the public, and insufficient data can hamper postflood recovery efforts. Central Texas is hilly, and it is known as a...
Authors
Namjeong Choi
By
Oklahoma-Texas Water Science Center

Flood-inundation maps for a 23-mile reach of the Medina River at Bandera, Texas, 2018 Flood-inundation maps for a 23-mile reach of the Medina River at Bandera, Texas, 2018

In 2018, the U.S. Geological Survey (USGS), in cooperation with the Bandera County River Authority and Groundwater District and the Texas Water Development Board, studied floods through the period of record to create a library of flood-inundation maps for the Medina River at Bandera, Texas. Digital flood-inundation maps for a 23-mile reach of the Medina River at and near Bandera, from...
Authors
Namjeong Choi, Frank Engel
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Flood warning toolset for the Medina River in Bandera County, Texas Flood warning toolset for the Medina River in Bandera County, Texas

Overview Floods are the most common natural disaster in the United States. The Medina River in Bandera County, Texas, is in the Edwards Plateau, where high-intensity rain rates and steep terrain frequently contribute to severe flash flooding capable of causing loss of life and property. For example, the July 5, 2002, flood claimed a total of 12 lives in the central Texas area. The...
Authors
Frank Engel, Namjeong Choi
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Science and Products

Flood waters carry large logs and inundate the base of trees

Identifying Opportunities to Strengthen Climate Resilience in Flood-Prone Urban Communities in Harris County, Texas

Project Overview Flooding in urban centers caused by increasingly severe storms has led to massive economic, social, and ecological damage. Researchers supported by this South Central CASC project will examine flood vulnerability and mitigation efforts in Harris County, Texas, currently home to the highest concentration of federally funded relocation projects in the country. The...
By
Climate Adaptation Science Centers
Identifying Opportunities to Strengthen Climate Resilience in Flood-Prone Urban Communities in Harris County, Texas

Identifying Opportunities to Strengthen Climate Resilience in Flood-Prone Urban Communities in Harris County, Texas

Project Overview Flooding in urban centers caused by increasingly severe storms has led to massive economic, social, and ecological damage. Researchers supported by this South Central CASC project will examine flood vulnerability and mitigation efforts in Harris County, Texas, currently home to the highest concentration of federally funded relocation projects in the country. The resulting flood
Learn More

Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934–2024 Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934–2024

The Edwards aquifer in south-central Texas is one of the most permeable and productive aquifers in the United States and is the major source of public water supply for Bexar, Comal, Hays, Medina, and Uvalde Counties. The Edwards aquifer also supplies large quantities of water for use in agriculture, business, and industry in the region. The major artesian springs of the Edwards aquifer...
By
Oklahoma-Texas Water Science Center

Datasets and R Scripts Used for the Water-Budget Analysis of the Medina and Diversion Lake System, Bandera, Bexar, and Medina Counties, Texas, 1955–2022 Datasets and R Scripts Used for the Water-Budget Analysis of the Medina and Diversion Lake System, Bandera, Bexar, and Medina Counties, Texas, 1955–2022

The U.S. Geological Survey—in cooperation with the San Antonio Water System and the Edwards Aquifer Authority—used data collected during four different periods (March 1955–August 1964, October 1995–September 1996, March 2001–June 2002, and March 2017–October 2022) as part of a new study to refine previously derived relations between the altitude of the water surface of Medina Lake and...
By
Oklahoma-Texas Water Science Center

Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934–2022 Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934–2022

The Edwards aquifer in south-central Texas is one of the most permeable and productive aquifers in the United States and is the major source of public water supply for Bexar, Comal, Hays, Medina, and Uvalde Counties. The Edwards aquifer also supplies large quantities of water for use in agriculture, business, and industry in the region. The major artesian springs of the Edwards aquifer...
By
Oklahoma-Texas Water Science Center

Geospatial and model dataset for flood-Inundation maps in a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021 Geospatial and model dataset for flood-Inundation maps in a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021

This data release documents the digital data used to produce flood-inundation maps for a range of gage heights (stages) for the Sabinal River near Utopia, Tex. The simulated flood-inundation maps correspond to a range in stage from 11 to 28 feet (ft) at U.S. Geological Survey (USGS) streamgage 08197970 Sabinal River at Utopia, Tex. at intervals of 0.5-ft. The maps were created for a 10...
By
Oklahoma-Texas Water Science Center

Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934 - 2020 Estimated Annual Recharge to the Edwards Aquifer in the San Antonio Area, by Stream Basin or Ungaged Area, 1934 - 2020

The Edwards aquifer in south-central Texas is one of the most permeable and productive aquifers in the United States and is the major source of public water supply for Bexar, Comal, Hays, Medina, and Uvalde Counties. The Edwards aquifer also supplies large quantities of water to agriculture, business, and industry in the region. The major artesian springs of the Edwards aquifer provide...
By
Oklahoma-Texas Water Science Center

Water-budget analysis of the Medina and Diversion Lake system, with estimated recharge to the Edwards aquifer and the upper zone of the Trinity aquifer, Bandera, Bexar, and Medina Counties, Texas, 1955–2022 Water-budget analysis of the Medina and Diversion Lake system, with estimated recharge to the Edwards aquifer and the upper zone of the Trinity aquifer, Bandera, Bexar, and Medina Counties, Texas, 1955–2022

The U.S. Geological Survey—in cooperation with the San Antonio Water System and the Edwards Aquifer Authority—used data collected during four different periods (March 1955–August 1964, October 1995–September 1996, March 2001–June 2002, and March 2017–October 2022) as part of a new study to refine previously derived relations between the altitude of the water surface of Medina Lake and...
Authors
Richard Slattery, Namjeong Choi, Allan K. Clark
By
Oklahoma-Texas Water Science Center

Component 1: Data and monitoring gap analysis Component 1: Data and monitoring gap analysis

The goal of Component 1 is to identify available data and data gaps in the Texas coastal region and to establish a plan for obtaining data critical for successful coastal flood analysis in these regions. This component is supporting the expansion and improvement of data observations for inland, coastal, and ocean systems.
Authors
David Wallace, Glenn Harwell, Namjeong Choi
By
Oklahoma-Texas Water Science Center

Flood-inundation maps created using a synthetic rating curve for a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021 Flood-inundation maps created using a synthetic rating curve for a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021

In 2021, the U.S. Geological Survey (USGS), in cooperation with the Bandera County River Authority and Groundwater District and the Texas Water Development Board, studied floods to produce a library of flood-inundation maps for the Sabinal River near Utopia, Texas. Digital flood-inundation maps were created for a 10-mile reach of the Sabinal River from USGS streamgage 08197936 Sabinal...
Authors
Namjeong Choi
By
Oklahoma-Texas Water Science Center

Flood warning toolset for the Sabinal River near Utopia, Texas Flood warning toolset for the Sabinal River near Utopia, Texas

Introduction Floods are one of the most frequent and expensive natural disasters that occur across the United States. Rapid, high-water events that occur in local areas—flash floods—are especially difficult for emergency managers to predict and provide advance warning to the public, and insufficient data can hamper postflood recovery efforts. Central Texas is hilly, and it is known as a...
Authors
Namjeong Choi
By
Oklahoma-Texas Water Science Center

Flood-inundation maps for a 23-mile reach of the Medina River at Bandera, Texas, 2018 Flood-inundation maps for a 23-mile reach of the Medina River at Bandera, Texas, 2018

In 2018, the U.S. Geological Survey (USGS), in cooperation with the Bandera County River Authority and Groundwater District and the Texas Water Development Board, studied floods through the period of record to create a library of flood-inundation maps for the Medina River at Bandera, Texas. Digital flood-inundation maps for a 23-mile reach of the Medina River at and near Bandera, from...
Authors
Namjeong Choi, Frank Engel
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Flood warning toolset for the Medina River in Bandera County, Texas Flood warning toolset for the Medina River in Bandera County, Texas

Overview Floods are the most common natural disaster in the United States. The Medina River in Bandera County, Texas, is in the Edwards Plateau, where high-intensity rain rates and steep terrain frequently contribute to severe flash flooding capable of causing loss of life and property. For example, the July 5, 2002, flood claimed a total of 12 lives in the central Texas area. The...
Authors
Frank Engel, Namjeong Choi
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center
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