Development and Application of a 1D Compaction Model to Understand 65 Years of Subsidence in the San Joaquin Valley


High rates of land subsidence, caused by groundwater overdraft, are resulting in millions of dollars of infrastructure damage in California's San Joaquin Valley (SJV). In recent years, the use of interferometric synthetic aperture radar (InSAR) has enabled us to substantially improve our understanding of this subsidence. However, only very occasionally have the InSAR data been integrated with a physical model of subsurface compaction. Here, we have used InSAR and other data to parameterize and calibrate a 1D compaction model. We applied our model to a study area in the SJV where we had access to the necessary information on hydraulic head to develop model inputs. Our model simulated subsidence in the three aquifer system layers over the period 1952-2017, and is the first 1D compaction model in the SJV to simulate multiple aquifer system layers from the 1950s to 2017. The results from our model suggest that previous studies have significantly underestimated the time constants governing the slow, residual compaction of subsurface clays. We suggest that residual compaction of clays is a process that continues for decades-to-centuries, indicating that to significantly reduce subsidence requires some recovery of head, not just a stabilization. We also show how compaction in the lower, confined aquifer has accounted for over 90% of subsidence in the past 20 years. Although our study area is small, our findings are likely representative of the subsiding regions of the SJV, and our methodology can be applied to unconsolidated aquifer systems exhibiting subsidence worldwide.


Geosciences and Geological and Petroleum Engineering


This work was funded by the Gordon and Betty Moore Foundation (Grant GBMF6189) and by the NASA Applied Sciences Water Resources Program in the Earth Science Division (Grant 80NSSC19K12480), with M. Lees supported by a Stanford Graduate Fellowship.

Keywords and Phrases

Groundwater Hydrology; Hydrogeophysics; Numerical Modeling; Remote Sensing; Water Management

International Standard Serial Number (ISSN)

1944-7973; 0043-1397

Document Type

Article - Journal

Document Version

Final Version

File Type





© 2022 Wiley; American Geophysical Union, All rights reserved.

Publication Date

01 Jun 2022

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