Geoff Cromwell, PhD
Geoff Cromwell is a Geologist, and Acting Program Chief for Groundwater Availability and Use, at the California Water Science Center in Santa Maria, California.
Dr. Cromwell's research explores hydrologic systems processes through the development of three-dimensional geologic and hydrogeologic framework models and integrating those models with groundwater, surface-water, and geophysical data. The scope of his work ranges from basin-scale to national-scale, from areas that are data-poor to areas that are data-rich, with a focus on understanding the geologic and hydrogeologic controls on hydrologic systems.
Science and Products
Filter Total Items: 42
Salinas and Carmel River Basins Study
Together, the Salinas and Carmel river basins include some of the world’s most fertile agricultural lands and are internationally known for their natural beauty; ecological diversity; multi-national cultural history; and recreation opportunities such as fishing, auto racing, and golfing. The area is oftentimes referred to as the “Salad Bowl of the World” or “America’s Salad Bowl” because of the...
SGMApy: An open source platform for computing sustainability metrics and visualizing MODFLOW data
Climate change and demographic changes have underscored the need to improve effectiveness of managing valuable water resources for sustainability. In 2014, the Sustainable Groundwater Management Act (SGMA) established a framework for sustainable, local groundwater management. SGMA requires groundwater-dependent regions to halt overdraft and bring basins into balanced levels of pumping and recharge...
Pajaro Valley Hydrologic Model Update, Data Collection, and Analysis for Sustainability
The Pajaro Valley is home to a billion-dollar agricultural industry, providing food and food processing services for the nation. The water for these enterprises is supplied, in large part, by the groundwater resources (aquifers) in the area. The Pajaro Valley Water Management Agency (PV Water) and the USGS have partnered to improve aquifer monitoring software, allowing better quantification and...
Cuyama Valley Water Availability Study
Currently, groundwater is the only source for domestic, agricultural and municipal water use in the Cuyama Valley groundwater basin in Santa Barbara County, California. Groundwater withdrawals, mainly to irrigate agricultural crops, have resulted in water-level declines of as much as 300 feet in the area since the 1940s. To plan for sustainable future use of the groundwater, the U.S. Geological...
Owens Valley Hydrogeology
The Owens Valley, a long, narrow valley along the east side of the Sierra Nevada in east-central California, is the main source of water for the city of Los Angeles. The city diverts most of the surface water in the valley into the Owens River-Los Angeles Aqueduct system, which transports the water more than 200 miles south to areas of distribution and use. Additionally, ground water is pumped or...
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 high and medium priority basins in the state. These GSAs must develop and implement Groundwater Sustainability Plans (GSPs) for managing and using groundwater...
Evaluation of the groundwater resources of the Petaluma Valley
The city of Petaluma, located in the Petaluma Valley and home to about 12 percent of the population of Sonoma County, faces growth in population and demand for water. Water supply is provided primarily by water delivered via aqueduct from the Russian River; however, groundwater is a vital supplemental source of water for the city of Petaluma and is the primary source of supply for domestic and...
Evaluation of water resources in Chuckwalla Valley, Riverside County, California
The Chuckwalla Valley in the southern Mojave Desert in California has been selected as an area with high potential for solar energy development. Six large-scale solar energy projects are currently approved or proposed in this basin, the largest number of solar projects in any one basin in California. Water needs associated with proposed solar energy projects within the basin have generated...
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.
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.
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.
Assessing the Feasibility of Artificial Recharge and Storage and the Effectiveness and Sustainability of Insitu Arsenic Removal in the Antelope Valley, California
Project Update - 8/2/2011: Water having an arsenic concentration of 30 micrograms per liter was infiltrated from a test pond beginning in December, 2010. After water moved downward through the unsaturated zone, arsenic concentrations in Lysimeters as deep as 110 ft beneath the pond were about 2 micrograms per liter. Laboratory column experiments show similar changes in arsenic concentrations in...
Science and Products
Filter Total Items: 42
Salinas and Carmel River Basins Study
Together, the Salinas and Carmel river basins include some of the world’s most fertile agricultural lands and are internationally known for their natural beauty; ecological diversity; multi-national cultural history; and recreation opportunities such as fishing, auto racing, and golfing. The area is oftentimes referred to as the “Salad Bowl of the World” or “America’s Salad Bowl” because of the...
SGMApy: An open source platform for computing sustainability metrics and visualizing MODFLOW data
Climate change and demographic changes have underscored the need to improve effectiveness of managing valuable water resources for sustainability. In 2014, the Sustainable Groundwater Management Act (SGMA) established a framework for sustainable, local groundwater management. SGMA requires groundwater-dependent regions to halt overdraft and bring basins into balanced levels of pumping and recharge...
Pajaro Valley Hydrologic Model Update, Data Collection, and Analysis for Sustainability
The Pajaro Valley is home to a billion-dollar agricultural industry, providing food and food processing services for the nation. The water for these enterprises is supplied, in large part, by the groundwater resources (aquifers) in the area. The Pajaro Valley Water Management Agency (PV Water) and the USGS have partnered to improve aquifer monitoring software, allowing better quantification and...
Cuyama Valley Water Availability Study
Currently, groundwater is the only source for domestic, agricultural and municipal water use in the Cuyama Valley groundwater basin in Santa Barbara County, California. Groundwater withdrawals, mainly to irrigate agricultural crops, have resulted in water-level declines of as much as 300 feet in the area since the 1940s. To plan for sustainable future use of the groundwater, the U.S. Geological...
Owens Valley Hydrogeology
The Owens Valley, a long, narrow valley along the east side of the Sierra Nevada in east-central California, is the main source of water for the city of Los Angeles. The city diverts most of the surface water in the valley into the Owens River-Los Angeles Aqueduct system, which transports the water more than 200 miles south to areas of distribution and use. Additionally, ground water is pumped or...
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 high and medium priority basins in the state. These GSAs must develop and implement Groundwater Sustainability Plans (GSPs) for managing and using groundwater...
Evaluation of the groundwater resources of the Petaluma Valley
The city of Petaluma, located in the Petaluma Valley and home to about 12 percent of the population of Sonoma County, faces growth in population and demand for water. Water supply is provided primarily by water delivered via aqueduct from the Russian River; however, groundwater is a vital supplemental source of water for the city of Petaluma and is the primary source of supply for domestic and...
Evaluation of water resources in Chuckwalla Valley, Riverside County, California
The Chuckwalla Valley in the southern Mojave Desert in California has been selected as an area with high potential for solar energy development. Six large-scale solar energy projects are currently approved or proposed in this basin, the largest number of solar projects in any one basin in California. Water needs associated with proposed solar energy projects within the basin have generated...
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.
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.
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.
Assessing the Feasibility of Artificial Recharge and Storage and the Effectiveness and Sustainability of Insitu Arsenic Removal in the Antelope Valley, California
Project Update - 8/2/2011: Water having an arsenic concentration of 30 micrograms per liter was infiltrated from a test pond beginning in December, 2010. After water moved downward through the unsaturated zone, arsenic concentrations in Lysimeters as deep as 110 ft beneath the pond were about 2 micrograms per liter. Laboratory column experiments show similar changes in arsenic concentrations in...