An Integrated Surface Water-Groundwater Interaction Model for the Carmel River

California State University, Monterey Bay | April 30th, 2010

The Carmel River supplies fresh water to the residents of the Monterey Peninsula within the water district served by the California American Water company (Cal-Am). The S

The Carmel River supplies fresh water to the residents of the Monterey Peninsula within the water district served by the California American Water company (Cal-Am). The State Water Resources Control Board, in 1995, ordered that Cal-Am reduce their annual diversions from the Carmel River Watershed to within legal right (3,376 acre-feet per year). An alternative water source to the Carmel River has yet to be determined, and as a result, Cal-Am must continue to divert more water than their legal entitlement. The current magnitude of diversions has a negative impact on the spawning and migrating habitat of Steelhead (Oncorhynchus mykiss). Existing software in the Tarsier Environmental Modeling Framework was used to model the spatial distribution of surface water along the Carmel River. The model simulated the flow of water downstream from catchment area to the Pacific Ocean. The river channel was represented by a network data set comprised of links, representing individual reaches of the river, connected by nodes. Prior to my work, systematic error in the model was thought to be partially the result of the model lacking a simulation of the interactions between the surface water and the underlying aquifer. A groundwater sub-model was developed to correct for the systematic error. The groundwater sub-model simulated the movement of water between the river channel and the aquifer. Stock variables representing a shallow and deep aquifer were added to each link of the network data set. Simulated water in the surface water stock of each link percolates to these aquifer stocks until the groundwater reaches aquifer capacity, allowing surface water to continue flowing downstream. The model also allows the lateral flow of groundwater according to Darcy’s Law. Quantitative and qualitative analysis of model output compared to observed data showed an increase in model accuracy. Quantitatively, a Nash- Sutcliff Coefficient was improved from 0.88 to 0.97 with the addition of the groundwater model. Qualitatively, a visualization of the longitudinal profile of the river system showed the simulated aquifer controlling the surface flow. A hypothetical application of this model is presented where reducing the pumping rate from the aquifer allowed the wetted river channel to increase by 2.5 km. Future work on the model should include a reservoir sub-model and accounting for spatial variability in the precipitation throughout the catchment area. With these improvements it will be possible to improve predictions of the spatial distribution of surface water along the Carmel River given hypothetical scenarios such as the rate and spatial distribution of pumping from the Carmel Aquifer. Using these simulations to inform decisions of river management could benefit all stakeholders of the river.

An Update of the Death Valley Regional Groundwater Flow System Transient Model, Nevada and California

U.S. Geological Survey (USGS) | October 31st, 2016

The U.S. Geological Survey (USGS) has revised the regional-scale Death Valley regional groundwater flow system (DVRFS) numerical model with new data and interpretations s

The U.S. Geological Survey (USGS) has revised the regional-scale Death Valley regional groundwater flow system (DVRFS) numerical model with new data and interpretations since the original numerical flow model was published in 2004 (Belcher (2004); re-published as Belcher and Sweetkind [2010]). Since the original publication of the DVRFS flow model, additional data have been collected and interpretations have been made. Cooperators such as the Bureau of Land Management, National Park Service, U.S. Fish and Wildlife Service, the Department of Energy, and Nye County, Nevada, recognized a need to update the existing regional numerical flow model to maintain its viability as a groundwater management tool for regional stakeholders. For the purposes of this report, the version of the DVRFS numerical flow model documented in Belcher and Sweetkind (2010) and Faunt, Blainey, and others (2010) is designated as DVRFS v. 1.0. The updated version, as presented in this report, is referred to as DVRFS v. 2.0. Knowledge of basin water balances and the magnitude of interbasin groundwater flow is the basis for regional groundwater management and water-resource planning in the Great Basin of Nevada (Scott and others, 1971). Rapid population growth, arid conditions, and increased water use have led to development of available groundwater resources. Groundwater use in some alluvial-fill basins has resulted in continued water-level declines and land subsidence. Adjacent bedrock aquifers are increasingly being targeted for additional development. Such groundwater development may potentially impact local and regional water quantity and quality, existing water rights, and wildlife habitats. An understanding of hydrogeologic processes that control the rate and direction of groundwater flow in southern Nevada is necessary to assess the potential effects of any proposed large-scale groundwater development. Potential water-resource conflicts exist because of disparate interests in the region, particularly with respect to the development of groundwater resources to meet agricultural, municipal, and industrial water demand and the need to protect habitat for endangered and threatened species. Water demands in the Amargosa Farms area from agricultural and suburban development, and rapidly urbanizing areas in Las Vegas and Pahrump Valleys place increasing pressure on existing groundwater resources. In addition, several solar-energy facilities have been proposed within the Death Valley region; water demands for these facilities will vary. Natural groundwater discharge at springs and seeps sustains habitat for numerous species, many of which are threatened, endangered, or otherwise considered sensitive. In 2004, the USGS documented a calibrated numerical flow model of the DVRFS (Belcher, 2004). The model, DVRFS v. 1.0, incorporated elements of several precursor numerical models but defined the boundaries of the regional flow system slightly different than in previous versions. The model simulates transient groundwater flow conditions in the DVRFS from 1913 through 1998. The report was subsequently revised and published as a USGS Professional Paper (Belcher and Sweetkind, 2010). Since release of DVRFS v. 1.0 in 2004, continued use of the model by cooperators, stakeholders, and interested parties in the region has demonstrated the need to improve specific aspects (such as the flow into northern Yucca Flat and parts of the Amargosa Desert), to update it with more recently acquired geologic and hydrologic data, and to extend the simulation period.

Analog Model Study of the Ground-Water Basin of the Upper Coachella Valley, California

U.S. Geological Survey (USGS) | July 18th, 1974

An analog model of the ground-water basin of the upper Coachella Valley was constructed to determine the effects of imported water on ground-water levels. The mod

An analog model of the ground-water basin of the upper Coachella Valley was constructed to determine the effects of imported water on ground-water levels. The model was considered verified when the ground-water levels generated by the model approximated the historical change in water levels of the ground-water basin caused by man's activities for the period 1936-67. The ground-water basin was almost unaffected by man's activities until about 1945 when ground-water development caused the water levels to begin to decline. The Palm Springs area has had the largest water-level decline, 75 feet since 1936, because of large pumpage, reduced natural inflow from the San Gorgonio Pass area, and diversions of natural inflows at Snow and Falls Creeks and Chino Canyon starting in 1945. The San Gorgonio Pass inflow had been reduced from about 13,000 acre-feet in 1936 to about 9,000 acre-feet by 1967 because of increased ground-water pumpage in the San Gorgonio Pass area, dewatering of the San Gorgonio Pass area that took place when the tunnel for the Metropolitan Water District of Southern California was drilled, and diversions ofsurface inflow at Snow and Falls Creeks. In addition, 1944-64 was a period of below-normal precipitation which, in part, contributed to the declines in water levels in the Coachella Valley. The Desert Hot Springs, Garnet Hill, and Mission Creek subbasins have had relatively little development; consequently, the water-level declines have been small, ranging from 5 to 15 feet since 1936. In the Point Happy area a decline of about 2 feet per year continued until 1949 when delivery of Colorado River water to the lower valley through the Coachella Canal was initiated. Since 1949 the water levels in the Point Happy area have been rising and by 1967 were above their 1936 levels. The Whitewater River subbasin includes the largest aquifer in the basin, having sustained ground-water pumpage of about 740,000 acre-feet from 1936 to 1967, and will probably continue to provide the most significant supply of ground water for the upper valley. The total ground-water storage depletion for the entire upper valley for 1936-67 was about 600,000 acre-feet, an average stor age decrease of about 25,000 acre-feet per year since 1945. Transmissivity for the Whitewater River subbasin ranges from 360,000 gal- lons per day per foot (near Point Happy) to 50,000 gallons per day per foot, with most of the subbasin about 300,000 gallons per day per foot. In contrast, the transmissivities of the Desert Hot Springs, Mission Creek, and Garnet Hill sub-basins generally range from 2,000 to 100,000, but the highest value, beneath the Mission Creek streambed deposits, is 200,000 gallons per day per foot; the transmissivity for most of the area of the three subbasins is 30,000 gallons per day per foot. The storage coefficients are representative of water-table conditions, ranging from 0.18 beneath the Mission Creek stream deposits to 0.06 in the Palm Springs area. The model indicated that the outflow at Point Happy decreased from 50,000 acre-feet in 1936 to 30,000 acre-feet by 1967 as a result of the rising water levels in the lower valley. The most logical area to recharge the Colorado River water is the Windy Point-Whitewater area, where adequate percolation rates of 2 4 acre-feet per acre per day are probable. The Whitewater River bed may be the best location to spread the water if the largest part of the imported water can be recharged during low-flow periods. The area in sec. 21, T. 2 S., R. 4 E., would be adequate for the smaller quantities of recharge proposed for the Mission Creek area. Projected pumpage for the period 1968-2000 was programed on the model with the proposed recharge of Colorado River water for the same period. The model indicated a maximum water-level increase of 200 feet above the 1967 water level at Windy Point, the proposed recharge site, by the year 2000, a 130-foot increase by 1990, and a 20-foot increase by 1980. The model indicated that the proposed quantities of recharge will beneficially affect the ground-water system to Palm Desert by 1980, to Point Happy by 1990, and possibly to the Coachella Canal by 2000. The model indicated that the upper and lower valleys are within the same hydrologic system, and it has been proposed that the model be extended to the Salton Sea. On the basis of the available analyses, changes in the quality of ground water in the Whitewater River subbasin after recharge apparently will be, as a first approximation, proportional to the ratio in which the quantity of recharge and the quantity of ground water are mixed. Where mixing does not occur, the quality of the recharge water will probably not be greatly changed by ion-exchange phenomenon.

Analysis and simulation of regional subsidence accompanying groundwater abstraction and compaction of susceptible aquifer systems in the USA

Mexican Geological Society (Sociedad Geológica Mexicana) | January 17th, 2013

Regional aquifer-system compaction and land subsidence accompanying groundwater abstraction in susceptible aquifer systems in the USA is a challenge for managing groundwa

Regional aquifer-system compaction and land subsidence accompanying groundwater abstraction in susceptible aquifer systems in the USA is a challenge for managing groundwater resources and mitigating associated hazards. Developments in the assessment of regional subsidence provide more information to constrain analyses and simulation of aquifer-system compaction. Current popular approaches to simulating vertical aquifer-system deformation (compaction), such as those embodied in the aquitard drainage model and the MODFLOW subsidence packages, have proven useful from the perspective of regional groundwater resources assessment. However, these approaches inadequately address related local-scale hazards—ground ruptures and damages to engineered structures on the land surface arising from tensional stresses and strains accompanying groundwater abstraction. This paper presents a brief overview of the general approaches taken by the U.S. Geological Survey toward understanding aquifer-system compaction and subsidence with regard to a) identifying the affected aquifer systems; b) making regional assessments; c) analyzing the governing processes; and d) simulating historical and future groundwater flow and subsidence conditions. Limitations and shortcomings of these approaches, as well as future challenges also are discussed 

Analysis of the Carmel Valley Alluvial Ground-Water Basin, Monterey County, California

U.S. Geological Survey (USGS) | June 14th, 1984

A two-dimensional, finite-element, digital model was developed for the Carmel Valley alluvial ground-water basin using measured, computed, and estimated discharge

A two-dimensional, finite-element, digital model was developed for the Carmel Valley alluvial ground-water basin using measured, computed, and estimated discharge and recharge data for the basin. Discharge data included evapotranspiration by phreatophytes and agricultural, municipal, and domestic pumpage. Recharge data included river leakage, tributary runoff, and pumping return flow. Recharge from subsurface boundary flow and rainfall infiltration was assumed to be insignificant. From 1974 through 1978, the annual pumping rate ranged from 5,900 to 9,100 acre-feet per year with 55 percent allotted to municipal use principally exported out of the valley, 44 percent to agricultural use, and 1 percent to domestic use. The pumpage return flow within the valley ranged from 900 to 1,500 acre-feet per year. The aquifer properties of transmissivity (about 5,900 feet squared per day) and of the storage coefficient (0.19) were estimated from an average alluvial thickness of 75 feet and from less well-defined data on specific capacity and grain-size distribution. During calibration the values estimated for hydraulic conductivity and storage coefficient for the lower valley were reduced because of the smaller grain size there. The river characteristics were based on field and laboratory analyses of hydraulic conductivity and on altitude survey data. The model is intended principally for simulation of flow conditions using monthly time steps. Time variations in transmissivity and short-term, high- recharge potential are included in the model. The years 1974 through 1978 (including "pre-" and "post-" drought) were selected because of the extreme fluctuation in water levels between the low levels measured during dry years and the above-normal water levels measured during the preceding and following wet years. Also, during this time more hydrologic information was available. Significantly, computed water levels were generally within a few feet of the measured levels, and computed flows were close to gaged river flows for this simulation. However, the nonuniqueness of solutions with respect to different sets of data indicates the model does not necessarily validate the correctness of the individual variables. The model might be improved with additional knowledge of the distribution of confining sediments in the lower end of the valley and the aquifer properties above and below them. The solution algorithm could account for confinement or partial confinement in the lower end of the valley plus contributions from the Tularcitos aquifer.

Anderson Subbasin Groundwater Sustainability Plan

Enterprise Anderson Groundwater Sustainability Agency | January 20th, 2022

This GSP covers all of the 98,700 acres of the Anderson Subbasin. The GSP describes the current groundwater conditions and hydrogeologic conceptual model, establishes a

This GSP covers all of the 98,700 acres of the Anderson Subbasin. The GSP describes the current groundwater conditions and hydrogeologic conceptual model, establishes a water budget, outlines local sustainable management criteria (SMC or SMCs), and describes projects and management actions for maintaining sustainability through the GSP planning and implementation period. Due to size, this file has been divided into 9 parts. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9

Annual Ground-Water Discharge by Evapotranspiration from Areas of Spring-Fed Riparian Vegetation Along the Eastern Margin of Death Valley, 2000–02

U.S. Geological Survey (USGS) | July 1st, 2006

Appraisal of the water resources of Death Valley, California–Nevada

U.S. Geological Survey (USGS) | December 1st, 1977

Approaches for groundwater management in times of depletion and regulatory change

University of California, Davis (UC Davis) | June 1st, 2018

New legislation and related regulations in California mandate groundwater management to avoid undesirable results from excessive groundwater pumping and other hum

New legislation and related regulations in California mandate groundwater management to avoid undesirable results from excessive groundwater pumping and other human activities. Required aspects of management planning that will occur in well over 100 alluvial groundwater sub-basins across the state include scientific foundation and public transparency. While the details of individual groundwater management approaches will be particular to conditions in each management area, there will be common elements based on similar aspects of many groundwater systems in the state. The process of beginning to implement groundwater management for a large part of the state poses challenges. Use of scientific knowledge and methods of analysis developed in academia and industry will be helpful to the overall effort. This dissertation considers aspects of groundwater management that are expected to be common among many planning efforts. Inactive water supply wells acting as conduits for contaminant migration is considered through field examples and use of recently available databases regarding existing well constructions and water quality. Nonpoint source pollution effects on groundwater quality from conduit wells are investigated and selective regulatory action is explored as an option for addressing an issue that is too large for complete solution with available resources. Options for managed aquifer recharge are explored for a combined urban-agricultural area through use of a recently released land use database. A hydro-economic analysis is performed using linear programming to evaluate the efficacy of an on-farm recharge approach. Future work may include development of additional insights within the context of the study areas presented as well as extensions that consider new geographic areas and additional related considerations.

Aquifer-system compaction and land subsidence: Measurements, analyses, and simulations-the Holly Site, Edwards Air Force Base, Antelope Valley, California

U.S. Geological Survey (USGS) | July 1st, 2000