Subsidence from Aquifer-Storage and Recovery in the East Bay Plain
The East Bay Municipal Utility District (EBMUD) has proposed to store and recover as much as 10 million gallons of water per day (MGD) at an aquifer storage and recovery (ASR) site, the Bayside Groundwater Project. Water will be stored in a 100-ft sequence of coarse-grained sediment (the "Deep Aquifer") underlying the East Bay Plain and the adjacent Niles Cone ground-water basin.
The Deep Aquifer is overlain by more than 500 ft of clayey fine-grained, sediments and likely underlain by comparable units. These sediments are similar to the clayey sediments found in the nearby Santa Clara Valley where inelastic compaction has resulted in 13 feet of subsidence. Thus, aquifer storage and recovery could cause subsidence around the southern East Bay Plain and might induce coastal flooding and reduce the ability of flood control channels to remove surface runoff from urbanized areas during storms. EBMUD needs to identify the potential for subsidence during ASR operations and develop subsidence monitoring tools that can be used to guide ASR operation.
The objective is to monitor, analyze and simulate aquifer-system compaction and expansion, and consequent land subsidence and ground inflation resulting from natural causes and any anthropogenic causes related to ground-water development and ASR activities at EBMUD's Bayside Groundwater Project.
Summary of Past Work/Background
The U.S. Geological Survey, in cooperation with the East Bay Municipal Utility District, carried out an investigation of aquifer-system deformation associated with groundwater-level changes at the Bayside Groundwater Project (BGP) near the San Francisco Bay shore in San Lorenzo, California (Sneed and others, 2015; fig. 1). As a part of the BGP, the East Bay Municipal Utility District (EBMUD) proposed an aquifer storage and recovery (ASR) program for up to 1 million gallons of water per day. To investigate the potential for aquifer-system compaction, expansion, and related subsidence and (or) uplift resulting from ASR activities, the USGS drilled three boreholes at one site (Bayside) next to the BGP. Inside one of the boreholes, six piezometers were constructed at various depths (one of which collapsed soon after construction). In each of the other two boreholes, a counterweighted pipe extensometer was installed at a depth of about 700 and 1,000 ft, respectively. Monitoring of the five piezometers and two extensometer sites continued into fiscal year (FY) 2023, however, as of December 2022, ASR activities have not yet been conducted by the EBMUD.
Objectives and Scope
The objective of this study is to collect and process groundwater and aquifer-system compaction data in association with Joint Funding Agreement (JFA) 20ZGJFA60084810_01. The scope of work will include up to eight site visits per FY to collect data, conduct quality-assurance and quality-control checks, and process continuous water-level and aquifer-system compaction data from the Bayside site. This proposal will ensure monitoring activities continue through FY 2027.
Approach
The approach will consist of two tasks: 1) USGS staff will make up to eight site visits each FY. During these visits, the USGS will service extensometers and monitoring wells. These services include inspecting and adjusting the equipment, downloading the extensometer and water-level data, and taking manual water-level and aquifer-system compaction measurements; and 2) the data will be reviewed and approved following USGS standards and stored in the National Water Information System, the USGS National database.
Lithostratigraphic, borehole-geophysical, hydrogeologic, and hydrochemical data from the East Bay Plain, Alameda County, California
Below are partners associated with this project.
The East Bay Municipal Utility District (EBMUD) has proposed to store and recover as much as 10 million gallons of water per day (MGD) at an aquifer storage and recovery (ASR) site, the Bayside Groundwater Project. Water will be stored in a 100-ft sequence of coarse-grained sediment (the "Deep Aquifer") underlying the East Bay Plain and the adjacent Niles Cone ground-water basin.
The Deep Aquifer is overlain by more than 500 ft of clayey fine-grained, sediments and likely underlain by comparable units. These sediments are similar to the clayey sediments found in the nearby Santa Clara Valley where inelastic compaction has resulted in 13 feet of subsidence. Thus, aquifer storage and recovery could cause subsidence around the southern East Bay Plain and might induce coastal flooding and reduce the ability of flood control channels to remove surface runoff from urbanized areas during storms. EBMUD needs to identify the potential for subsidence during ASR operations and develop subsidence monitoring tools that can be used to guide ASR operation.
The objective is to monitor, analyze and simulate aquifer-system compaction and expansion, and consequent land subsidence and ground inflation resulting from natural causes and any anthropogenic causes related to ground-water development and ASR activities at EBMUD's Bayside Groundwater Project.
Summary of Past Work/Background
The U.S. Geological Survey, in cooperation with the East Bay Municipal Utility District, carried out an investigation of aquifer-system deformation associated with groundwater-level changes at the Bayside Groundwater Project (BGP) near the San Francisco Bay shore in San Lorenzo, California (Sneed and others, 2015; fig. 1). As a part of the BGP, the East Bay Municipal Utility District (EBMUD) proposed an aquifer storage and recovery (ASR) program for up to 1 million gallons of water per day. To investigate the potential for aquifer-system compaction, expansion, and related subsidence and (or) uplift resulting from ASR activities, the USGS drilled three boreholes at one site (Bayside) next to the BGP. Inside one of the boreholes, six piezometers were constructed at various depths (one of which collapsed soon after construction). In each of the other two boreholes, a counterweighted pipe extensometer was installed at a depth of about 700 and 1,000 ft, respectively. Monitoring of the five piezometers and two extensometer sites continued into fiscal year (FY) 2023, however, as of December 2022, ASR activities have not yet been conducted by the EBMUD.
Objectives and Scope
The objective of this study is to collect and process groundwater and aquifer-system compaction data in association with Joint Funding Agreement (JFA) 20ZGJFA60084810_01. The scope of work will include up to eight site visits per FY to collect data, conduct quality-assurance and quality-control checks, and process continuous water-level and aquifer-system compaction data from the Bayside site. This proposal will ensure monitoring activities continue through FY 2027.
Approach
The approach will consist of two tasks: 1) USGS staff will make up to eight site visits each FY. During these visits, the USGS will service extensometers and monitoring wells. These services include inspecting and adjusting the equipment, downloading the extensometer and water-level data, and taking manual water-level and aquifer-system compaction measurements; and 2) the data will be reviewed and approved following USGS standards and stored in the National Water Information System, the USGS National database.
Lithostratigraphic, borehole-geophysical, hydrogeologic, and hydrochemical data from the East Bay Plain, Alameda County, California
Below are partners associated with this project.