Steve Ackley (Former Employee)
Science and Products
Filter Total Items: 126
Effects of Climate on Snowmelt and Water Availability for Reservoirs in the Southern Sierra Nevada
Potential changes in air temperature and precipitation due to changes in climate may result in more variable or smaller snow packs and earlier snowmelt in the southern Sierra Nevada in upcoming years. These conditions are likely to result in increased difficulty in planning reservoir operations for hydroelectric power and water availability during springtime snowmelt in this region. Reservoir...
Assessing the Feasibility of Artificial Recharge and Storage and the Effectiveness and Sustainability of Insitu Arsenic Removal in the North Buttes Area, Antelope Valley, California
Groundwater pumpage for agricultural and municipal supply has resulted in water-level declines of more than 200 ft in some parts of the Antelope Valley groundwater basin and land subsidence of more than 6 ft in some areas. Future urban growth, increased agricultural demand, and limits on the supply of imported water will continue to increase the demand for groundwater.
Spatially Explicit Mapping of Hydrologic Residence Time Paired with Water Quality Measurements to Determine the Effects of the Emergency Drought Barrier
The purpose of this study is to assess the distribution of water residence times across the central Delta using rapid water isotope measurements (δ2H, δ18O) made with a boat-based flow-through instrument.
Simulation of Water Resources Management in the Pajaro Valley
Two key hydrologic issues in all coastal aquifer systems are the delineation and the management of the renewable water resources. The proper development and management of the renewable resources helps to minimize ground-water mining of the lower aquifer systems, and minimizes overdraft and seawater intrusion of the upper aquifer system while maximizing the sustainable yield of the renewable water...
Hydrogeologic Characterization of the Modesto Area Ground-Water Basin and Evaluation of Water Resource Management Alternatives
Strategies for managing local water supplies and ground-water quality are being formulated and evaluated by the Stanislaus-Tuolumne River Groundwater Basin Association (STRGBA).
Variability of Salinity and Temperature In San Francisco Bay
The USGS has been collecting specific conductance (salinity) and water temperature data in San Francisco Bay (SF Bay) since 1990. Data are typically collected at 5-10 fixed locations throughout the bay, every fifteen minutes, every minute of the day.
High-Speed Mapping of Nutrient Distributions and Water Quality Survey - Lower South San Francisco Bay
This project aims to characterize spatial heterogeneity for key water quality parameters, and pilot the use of underway-flowthrough mapping of biogeochemical properties as a cost-effective approach to monitoring.
Assessment of Baseline Conditions in Liberty Cut
Monitoring habitat quality in the San Francisco Estuary (SFE) and Sacramento-San Joaquin Delta has been limited to mostly monthly discrete measurements of biologically relevant parameters (e.g. phytoplankton, dissolved organic matter (DOM), nutrients) that cannot fully characterize the physical and biogeochemical variability.
Evaluating coagulation techniques to reduce the transport of Hg from mine-affected and active geothermal Hg-source watersheds
Our objective is to determine the effectiveness of coagulation and adsorption techniques in removing mercury from contaminated surface waters of the Cache Creek watershed.
Dynamics of zooplankton in the Cache Slough Complex
Our purpose is to investigate what controls the distribution and abundance of fish prey within the Cache Slough Complex (CSC).
Optimal Groundwater Sustainability, Santa Barbara, California
Prior to 1997, local surface water and groundwater supplied all of the water supply for the city of Santa Barbara (about 120 miles northwest of Los Angeles). Excess pumping of groundwater during times of drought resulted in saltwater intrusion in Storage Unit I of the Santa Barbara groundwater basin.
Phytoplankton production and nutrient transformations in shallow water wetland habitats
The objectives of this study are to quantify and characterize (1) phytoplankton production on Liberty Island, (2) utilization and transformation of nutrients, and (3) attenuation/loss of phytoplankton as the material is transported from Liberty Iisland into Cache Slough.
Science and Products
Filter Total Items: 126
Effects of Climate on Snowmelt and Water Availability for Reservoirs in the Southern Sierra Nevada
Potential changes in air temperature and precipitation due to changes in climate may result in more variable or smaller snow packs and earlier snowmelt in the southern Sierra Nevada in upcoming years. These conditions are likely to result in increased difficulty in planning reservoir operations for hydroelectric power and water availability during springtime snowmelt in this region. Reservoir...
Assessing the Feasibility of Artificial Recharge and Storage and the Effectiveness and Sustainability of Insitu Arsenic Removal in the North Buttes Area, Antelope Valley, California
Groundwater pumpage for agricultural and municipal supply has resulted in water-level declines of more than 200 ft in some parts of the Antelope Valley groundwater basin and land subsidence of more than 6 ft in some areas. Future urban growth, increased agricultural demand, and limits on the supply of imported water will continue to increase the demand for groundwater.
Spatially Explicit Mapping of Hydrologic Residence Time Paired with Water Quality Measurements to Determine the Effects of the Emergency Drought Barrier
The purpose of this study is to assess the distribution of water residence times across the central Delta using rapid water isotope measurements (δ2H, δ18O) made with a boat-based flow-through instrument.
Simulation of Water Resources Management in the Pajaro Valley
Two key hydrologic issues in all coastal aquifer systems are the delineation and the management of the renewable water resources. The proper development and management of the renewable resources helps to minimize ground-water mining of the lower aquifer systems, and minimizes overdraft and seawater intrusion of the upper aquifer system while maximizing the sustainable yield of the renewable water...
Hydrogeologic Characterization of the Modesto Area Ground-Water Basin and Evaluation of Water Resource Management Alternatives
Strategies for managing local water supplies and ground-water quality are being formulated and evaluated by the Stanislaus-Tuolumne River Groundwater Basin Association (STRGBA).
Variability of Salinity and Temperature In San Francisco Bay
The USGS has been collecting specific conductance (salinity) and water temperature data in San Francisco Bay (SF Bay) since 1990. Data are typically collected at 5-10 fixed locations throughout the bay, every fifteen minutes, every minute of the day.
High-Speed Mapping of Nutrient Distributions and Water Quality Survey - Lower South San Francisco Bay
This project aims to characterize spatial heterogeneity for key water quality parameters, and pilot the use of underway-flowthrough mapping of biogeochemical properties as a cost-effective approach to monitoring.
Assessment of Baseline Conditions in Liberty Cut
Monitoring habitat quality in the San Francisco Estuary (SFE) and Sacramento-San Joaquin Delta has been limited to mostly monthly discrete measurements of biologically relevant parameters (e.g. phytoplankton, dissolved organic matter (DOM), nutrients) that cannot fully characterize the physical and biogeochemical variability.
Evaluating coagulation techniques to reduce the transport of Hg from mine-affected and active geothermal Hg-source watersheds
Our objective is to determine the effectiveness of coagulation and adsorption techniques in removing mercury from contaminated surface waters of the Cache Creek watershed.
Dynamics of zooplankton in the Cache Slough Complex
Our purpose is to investigate what controls the distribution and abundance of fish prey within the Cache Slough Complex (CSC).
Optimal Groundwater Sustainability, Santa Barbara, California
Prior to 1997, local surface water and groundwater supplied all of the water supply for the city of Santa Barbara (about 120 miles northwest of Los Angeles). Excess pumping of groundwater during times of drought resulted in saltwater intrusion in Storage Unit I of the Santa Barbara groundwater basin.
Phytoplankton production and nutrient transformations in shallow water wetland habitats
The objectives of this study are to quantify and characterize (1) phytoplankton production on Liberty Island, (2) utilization and transformation of nutrients, and (3) attenuation/loss of phytoplankton as the material is transported from Liberty Iisland into Cache Slough.