An Overview of Groundwater-Related Land Lowering in Texas

Subsidence refers to the gradual sinking or lowering of the ground surface that can occur when groundwater is withdrawn faster than it can naturally recharge.
As water is pumped from aquifers, the pressure that supports surrounding soil and sediment layers decreases. Over time, this pressure loss can cause fine-grained materials, such as clays, to compact, resulting in measurable land elevation changes.

Mechanism of Groundwater-Related Subsidence

  • Aquifer Compaction: Groundwater occupies pore spaces between sediment grains. When water is removed, pore pressure drops, allowing sediments to compress under their own weight.

  • Irreversible Storage Loss: In clay-rich aquifers, this compaction is typically permanent, reducing the aquifer’s ability to store water in the future.

  • Influencing Factors: Deeper wells, higher pumping rates, and long-term withdrawals increase the potential for subsidence.

Examples in Texas

Houston–Galveston Region

  • Aquifers: Gulf Coast Aquifer system (Chicot, Evangeline, Jasper formations).

  • Background: Since the 1920s, areas of Harris and Galveston Counties have experienced land elevation changes exceeding 10 feet, linked to historical groundwater withdrawals for municipal, industrial, and agricultural use.

  • Response: The Harris–Galveston Subsidence District was created in 1975 to manage groundwater use and reduce further land-surface lowering.

  • Impacts Observed: Changes in drainage patterns, localized flooding, and long-term infrastructure stress.

Houston Ship Channel

  • Subsidence in this industrial corridor has contributed to several feet of land-surface change, influencing drainage gradients and increasing flood vulnerability.

  • The transition from groundwater to surface water supplies has helped stabilize ground levels in many areas.

Lower Rio Grande Valley

  • Aquifers: Gulf Coast Aquifer local units.

  • Findings: Localized and moderate subsidence has been measured in Cameron and Hidalgo Counties, primarily associated with groundwater withdrawals for irrigation.

El Paso and West Texas Region

  • Aquifer: Hueco Bolson

  • Findings: Evidence of land subsidence and ground fissures related to historical groundwater use for municipal and industrial supply in El Paso and Ciudad Juárez.

  • These findings encouraged the use of Rio Grande surface water and aquifer storage and recovery strategies to maintain regional water supply reliability.

Educational Video Example

🎥 Watch: “The Shocking Truth Behind Baytown’s Abandoned Neighborhood”

Description (for educational context):
This short video provides a visual example of how land subsidence has affected portions of the Baytown, Texas, area — historically linked to significant groundwater level declines during the mid-20th century.
It is shared here for public education and awareness purposes to illustrate real-world examples of subsidence impacts documented in Texas.

Monitoring and Management

Subsidence is monitored in Texas using ground-based and satellite methods, including:

  • InSAR (Interferometric Synthetic Aperture Radar)

  • GPS networks

  • Groundwater elevation monitoring through well measurements

These data help identify areas of land-surface change and guide state and local planning efforts to support sustainable groundwater use.

In Summary

Groundwater-related subsidence is a scientifically documented phenomenon that has occurred in multiple regions of Texas, particularly in areas with high groundwater use and clay-rich aquifer materials.
Understanding how and why subsidence occurs allows landowners, planners, and conservation districts to better evaluate groundwater conditions, inform planning decisions, and manage water resources responsibly under Texas’s local management framework.

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Where We Are in the Process of Creating the Nueces Groundwater Conservation District (NGCD)

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Groundwater in Texas: Understanding Regional Planning, Exports, and Anticipated Demand