California Water Science Center

Land Subsidence

Land Subsidence in California

Land Subsidence in California

Explore what causes land subsidence, how it is measured, and what areas of California have been affected. 

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Sustainable Groundwater Management Act (SGMA)

Sustainable Groundwater Management Act (SGMA)

USGS data, modeling tools, and scientific analysis to help water resource managers plan for, and assess, hydrologic issues associated with groundwater use and the SGMA sustainability indicators.

SGMA Tools & Info >>
Filter Total Items: 30
Date published: June 12, 2019
Status: Active

Land Subsidence in California

Extensive groundwater withdrawals from aquifer systems have caused land subsidence in many California basins. Land subsidence can cause infrastructure damage, not only to buildings and roads but also to water conveyence systems. Groundwater-level and land-subsidence monitoring provide the information needed to guide mitigation efforts and management of future effects.

Date published: December 20, 2018
Status: Active

Sustainable Groundwater Management

In 2014, the State of California adopted historic legislation to help manage its groundwater, the Sustainable Groundwater Management Act (SGMA) . According to the act, local Groundwater Sustainability Agencies (GSAs) must be formed for all...

Contacts: Claudia C Faunt
Date published: December 20, 2018
Status: Active

California's Central Valley

Competition for water resources is growing throughout California, particularly in the Central Valley. The Central Valley's population is expected to increase to 6 million by 2020. This population growth, along with anticipated reductions in Colorado River water deliveries, drought, and the ecological crisis in the Sacramento-San Joaquin Delta, have created an intense demand for water. The...

Contacts: Claudia C Faunt
Date published: December 19, 2018
Status: Active

California Drought

The USGS closely monitors the effects of drought through data collection and research. USGS science supports water managers in preparing for possible future drought by providing information that takes into account long-term hydrologic, climatic, and environmental changes. These studies support successful planning and science-based decision-making by water managers who must address complex...

Date published: December 19, 2018
Status: Completed

Optimization of Operation of Yuma Area Drainage and Regulatory Wells - Pilot Project

Reclamation's Yuma Area Office (YAO) operates 50 plus drainage wells and 21 regulatory wells to control groundwater levels in low-lying flood plain areas and to supply a significant portion of the Colorado River water the United States (US) is required by treaty to deliver to Mexico.

Date published: December 19, 2018
Status: Completed

Determining the fate and transport of septic-tank effluent in the southern area of Warren subbasin, California

Residents and businesses in Yucca Valley, CA rely currently on septic tanks to treat their wastewater. The local water district, Hi-Desert Water District (HDWD), is planning to construct a sewer system and wastewater treatment plant, initially serving the West, Midwest, Mideast, Northeast, and East hydrogeologic units of the Warren subbasin.

Date published: December 19, 2018
Status: Completed

Sonoma Valley Surface Water/Groundwater-Flow Model

Sonoma County faces potential changes in surface-water availability, including potential impacts on water quality in response to changing land use, increasing population, and climate change.

Contacts: Tracy Nishikawa
Date published: December 18, 2018
Status: Active

Water-Level, Water-Quality and Land-Subsidence Studies in the Mojave River and Morongo Groundwater Basins

Groundwater has been the primary source of domestic, agricultural, and municipal water supplies in the southwestern Mojave Desert, California, since the early 1900s. The population of the Mojave River and Morongo groundwater basins has grown rapidly during the last several decades, increasing from an estimated population of almost 273,000 in 1990 (...

Date published: December 13, 2018
Status: Active

Continuous Global Positioning System (CGPS) Stations

Measurements of elevations, aquifer-system compaction, and water levels are used to improve our understanding of the processes responsible for land-surface elevation changes. Elevation or elevation-change measurements are fundamental to monitoring land subsidence, and have been measured by using continuous GPS (CGPS) measurements and campaign global positioning system (GPS) surveying. ...

Contacts: Michelle Sneed
Date published: December 7, 2018
Status: Active

Spirit Leveling

Elevation or elevation-change measurements are fundamental to monitoring land subsidence, and have been measured by using interferometric synthetic aperture radar (InSAR), continuous GPS (CGPS) measurements, campaign global positioning system (GPS) surveying, and spirit-leveling surveying. The most precise measurements tend to be made using spirit-leveling surveys and extensometers. 

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Contacts: Michelle Sneed
Date published: December 7, 2018
Status: Active

Interferometric Synthetic Aperture Radar (InSAR)

Interferometric Synthetic Aperture Radar (InSAR) is an effective way to measure changes in land surface altitude. InSAR makes high-density measurements over large areas by using radar signals from Earth-orbiting satellites to measure changes in land-surface altitude at high degrees of measurement resolution and spatial detail (Galloway and others, 2000).

Synthetic Aperture...

Contacts: Michelle Sneed
Date published: December 6, 2018
Status: Completed

Land Subsidence in the Santa Clara Valley

Throughout the late 1800s and into the 1920s when two thirds of the Santa Clara Valley had been irrigated, water flowed freely from wells. Water-level declines of more than 200 ft occurred in the Santa Clara Valley from the early 1900's to the mid 1960's (Fowler, 1981). Land subsidence was first detected in 1933 (...

Contacts: Michelle Sneed