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Zirconium (Zr) stable isotopes recently emerged as potential tracers of magmatic processes and, as a result, their behavior in high-temperature environments have been the focus of extensive characterization. In contrast, few studies have focused on Zr behavior and isotopic fractionation in low temperature or aqueous environments. Here, we describe a new analytical routine for highly precise and accurate analysis of Zr isotopes of water samples, using a combination of double-spike and iron co-precipitation methods. To assess the impact of potential systematic biases a series of experiments were conducted on natural and synthetic water samples. Our results show that the spike-to-sample ratio, matrix composition, and high field-strength element (HFSE) concentration have negligible effects on measured seawater Zr isotopic compositions, and that the Fe co-precipitation method used yields accurate and precise Zr isotope data. We thus apply this method to natural seawater samples collected from a water column profile in the Pacific Ocean off the coast of California, with depths ranging from 5 to 711 m. We find that the natural seawater samples are highly fractionated relative to solid-Earth values and display marked variability in δ 94/90Zr as a function of depth, ranging from ∼ +0.650 ‰ near the surface, to + 1.530 ‰ near the profile bottom, with an analytical uncertainty of ± ∼0.045 ‰ (2 SE, external reproducibility). The δ 94/90Zr value of seawater is much higher than that of Earth's mantle and continental crust, which has a δ 94/90Zr value near zero, indicating the presence of processes in the hydrosphere capable of inducing large mass-dependent fractionation. Furthermore, the seawater δ 94/90Zr value exhibits systematic variations with respect to water depth and salinity, suggesting that Zr isotopic compositions may be sensitive to seawater chemical properties and source highlighting its potential utility as a tracer of biogeochemical processes within the ocean. [ABSTRACT FROM AUTHOR]

This interview begins a conversation about the social justice implications of an emerging socioecological concern—the desalination industry. Seawater desalination is the industrial process of creating drinking water from the ocean. This dialogue, with two activists at the forefront of contesting desalination in California, indicates how this practice, as a proposed climate adaptation strategy, is not just a matter of crafting governance reforms allowing non-state actors to price water for the purposes of efficient management, or "drought-proofing." Instead, they highlight the ways in which the environmental justice movement now faces a world-system of shareholder, equity-partnered, and pension-funded capitalism that is fragmenting nature and crafting an ever more abstract social nature into various, segmented resource types. As the dialogue describes, desalination is not pursued for the purposes of developing affordable and sustainable water management solutions alone, but for investment in long-duration fixed capital "assets." This piece further facilitates the programs of environmental sociology and political ecology by engaging various publics in developing a community of critical praxis. As such, the dialogue carves out new terrains of theory and action at the frontiers of nature, water, and society. [ABSTRACT FROM AUTHOR]

This study analyzed the economic factors of geothermal energy source utilization for desalination and power generation near Salton Sea, California. Three following over-arching reasons provided impetus for this study: geothermal source temperature, drinking water needs, and aquifer quality. The Cost of Renewable Energy Spreadsheet Tool (CREST) Model was used to determine the feasibility of three major desalination processes with low and medium temperature geothermal sources as thermal and electrical energy sources. Electrical energy, produced by medium temperature geothermal sources (100–200 °C), was considered for desalination (water) only and desalination and power (water and power) schemes through ten different scenarios using different desalination plant capacities (20,000–30,000 m3/d) and specific energy demands (40–80 kWh/m3). Low-temperature geothermal source was considered for meeting the thermal energy requirements of MED desalination plant supported by grid electricity with four different scenarios, which include new wells (full-size and slim-hole) and existing wells (existing without modification and existing with brine reinjection). Results from the analysis show that low enthalpy geothermal wells provide cost-effective option for desalination only configuration supported by conventional electricity. Medium-temperature geothermal source provided an affordable cost scenario when water and power scheme was considered. It was noted that the majority of freshwater cost ranges were due to the geothermal energy costs which were 1.97–2.39 $/m3, 1.95–2.35 $/m3, 1.75–1.96 $/m3 and 1.66–1.77 $/m3, for new full-size geothermal wells, new slim-hole geothermal well, existing, and existing geothermal well reinjection stream options, respectively. When conventional electricity is considered for desalination, the energy costs varied between 0.52 and 1.14 $/m3 for new full size well option considering different desalination capacities (20,000–30,000 m3/d) and specific energy consumption vales (40–80 kWh/m3). Finally, the lowest freshwater cost option was still 50–100% higher than the conventional water supply options in the region. However, combining factors of high groundwater salinity and high geothermal resource availability suggested geothermal desalination option as an environmentally benign approach for this region. [ABSTRACT FROM AUTHOR]

Solar electricity enables the advancement and deployment of technologies that are strongly influenced by clean energy availability and cost. The economics of both desalination and hydrogen production from water electrolysis are dominated by the cost of energy, and the availability of inexpensive solar energy creates markets and offers incentives to the desalination and electrolyzer industries. Herein, production of high‐purity water and hydrogen from seawater is focused on. Current electrolyzers require deionized water so they need to be coupled with desalination units. It is shown that such coupling is cost effective in hydrogen generation, and it also offers benefits to thermal desalination, which can utilize waste heat from electrolysis. Furthermore, such coupling can be optimized when electrolyzers operate at high current density, using low‐cost solar and/or wind electricity, as such operation increases both hydrogen production and heat generation. Results of technoeconomic modeling of polymer electrolyte membrane electrolyzers define thresholds of electricity pricing, current density, and operating temperature that make clean electrolytic hydrogen cost competitive with hydrogen from steam methane reforming (SMR). By using 2020 hourly electricity pricing in California and Texas, it is estimated that hydrogen can be produced from seawater in coupled desalination−electrolyzer systems at prices near $2 kg−1 H2, reaching cost parity with hydrogen produced from SMR. [ABSTRACT FROM AUTHOR]

• An innovative integration of compressed air energy storage and desalination units. • Comprehensive thermodynamic, exergoeconomic, and economic assessments of the system. • A comparative study of the performance of the proposed system with isobaric and isochoric tanks. • Achieving an energy and exergy round-trip efficiency of 62.18% and 57.84%. • Achieving a payback period of 3.82 years with a total profit of $27.65 million for the case study. Electricity and potable water are two vital resources for the world's population. A pioneering green energy storage system for power and potable water production has been introduced and investigated in this context. The innovative system integrates compressed air, pumped hydro, and thermal energy storage, along with multi-effect desalination. This combination enables the generation of power and potable water without exerting any adverse impact on the environment. This technology manages the start-up time of the desalination unit by using a low thermal energy storage unit and allows potable water to be generated throughout the day. By conducting a comprehensive analysis including energy, exergy, economic, and exergoeconomic, the performance of the system has been carefully examined and the effect of various parameters has also been considered. Finally, the advantages of the proposed system are compared to the conventional system. According to the study, round trip efficiency and total cost rate have been calculated as 62.18% and 618.6 USD/hr, respectively. Based on a case study conducted in the coastal areas of the state of California, the proposed system has the potential to generate 138 m3 of potable water and 88.11 MWh of electricity per day. This could lead to a total profit of 27.65 million dollars with a payback period of 3.82 years. [ABSTRACT FROM AUTHOR]

Water desalination is a proposed solution for mitigating the effects of drought, soil salinization, and the ecological impacts of agricultural drainage. In this study, we assess the public and private costs and benefits of distributed desalination in the Central Valley (CV) of California. We employ environmental and economic modeling to estimate the value of reducing the salinity of irrigation water; the value of augmenting water supply under present and future climate scenarios; and the human health, environmental, and climate change damages associated with generating power to desalinate water. We find that water desalination is only likely to be profitable in 4% of the CV during periods of severe drought, and that current costs would need to decrease by 70–90% for adoption to occur on the median acre. Fossil-fuel powered desalination technologies also generate air emissions that impose significant public costs in the form of human health and climate change damages, although these damages vary greatly depending on technology. The ecosystem service benefits of reduced agricultural drainage would need to be valued between $800 and $1200 per acre-foot, or nearly the full capital and operational costs of water desalination, for the net benefits of water desalination to be positive from a societal perspective. [ABSTRACT FROM AUTHOR]

Solar stills are conventional desalination systems based on direct solar heating. While their productivity is limited, their simple construction and low maintenance requirements makes them an attractive and feasible option for community-scale desalination. This study shows that low-cost solar stills are capable of producing sufficient freshwater for small disadvantaged communities at costs lower than competing technologies. A variety of solar still materials are investigated showing that the cost of freshwater produced is sensitive to the solar still cost. Inexpensive carbon black particles dispersed in the water are used to increase solar still performance, and a set of low-cost solar still materials are identified from a pool of candidate materials to minimize water production cost by means of optical and energy analyses. In addition, communities with fewer than 10000 residents are identified in the reference region of California to perform an energy analysis to determine freshwater productivity yield and the cost of freshwater production. It is determined that a 10000 m 2 solar still could produce freshwater meeting the requirements of small rural communities costing less than $ 7.71 / m 3. Attractive investment options are available that could reduce the cost of water produced to less than $ 1.75 / m 3. Solar stills were found to be feasible when comparing the cost of freshwater produced with a comparable photovoltaic reverse osmosis system. The proposed methodology can be extrapolated to determine the feasibility of solar still-based desalination systems in other geographical locations. From the results of the analysis, solar stills are proposed for effectively producing low-cost freshwater to increase the accessibility of freshwater in small rural communities. [Display omitted] • Low-cost solar stills can produce freshwater for rural communities at competitive costs • Several solar-still materials were studied for sensitivity analysis of freshwater cost • Inexpensive carbon black particles dispersed in water increase solar still performance • A LCOW analysis is performed to analyze the cost of freshwater produced [ABSTRACT FROM AUTHOR]

This article examines coastal residents' awareness and knowledge about impacts of seawater desalination on marine ecosystems Carlsbad, California. The paper explores to what extent sociodemographics, motivational factors, and information use shape public awareness and self-assessed and factual knowledge. Data was collected using a mail survey (n=330) from a random sample of residents in Carlsbad. Both self-assessed and factual knowledge about the desalination plant and its impacts on marine ecosystem were low, with only two of 11 factual questions answered correctly by more than 50% of respondents. Gender, frequency of ocean use, and use of distinct information sources correlated positively with greater factual knowledge. Education, age, time of residency in local community, membership in an NGO, and place attachment to marine areas did not increase factual knowledge. Findings also demonstrate that knowledge shaped attitudes towards the seawater desalination plant as greater knowledge about marine impacts reduced support. [ABSTRACT FROM AUTHOR]

The article discusses the use of desalination of ocean water as a supplement to California's water supply to alleviate the burden on stripped environments such as the Colorado River. Topics discussed include implementation of desalination could enhance international relations between the U.S. and Mexico, Californians and Mexicans need of water; and impact of climate change on water availability.

A seawater reverse osmosis (SWRO) desalination plant collocated with an existing nuclear plant would have low electricity costs, could share the power plant's seawater intake and outfall, and would have zero carbon footprint during operation. Unlike thermal desalination technologies, electrically-driven SWRO is ideal for retrofitting existing power plants because the turbines and condensers would not need expensive modifications. Here, we evaluate the techno-economic feasibility of collocating a large-scale SWRO plant with an existing nuclear power plant, specifically the 2.2 GW e Diablo Canyon Nuclear Power Plant on California's central coast. The seawater that cools the nuclear plant's condensers provides the feed water for desalination. The desalination brine is diluted with the remaining condenser coolant before being discharged to the ocean. A brushed-screen intake structure, serving both the nuclear power plant and the desalination plant, can comply with strict California regulations protecting marine organisms. This coproduction arrangement has a significant cost advantage relative to a stand-alone desalination plant. The levelized cost of water (LCOW) ranges from US$0.77 to US$0.98 per m3 of fresh water, with water distribution to offtakers adding US$0.02 to US$0.21 per m3 over 20–185 km. In comparison, California's largest desalination plant, in Carlsbad, has an LCOW of about US$1.84 per m3. These cost savings result from reduced power costs (about US$0.054 per kWh) and from sharing some expensive infrastructure. Further, nuclear electricity allows a Carlsbad-size SWRO to avoid 47 kt/y of CO 2 emissions relative to grid electricity. Examination of substantially larger desalination plants introduces additional considerations. This study is the first to show that collocated SWRO and nuclear power are strongly coupled and have a significant economic advantage over seawater desalination at other sites. These benefits should apply to dozens of existing nuclear power plants worldwide. • Collocating reverse osmosis with nuclear power results in a 50% water cost savings. • Strong coupling results from shared infrastructure and reduced electricity cost. • Reverse osmosis is ideally suitable for retrofitting existing nuclear plants. • Brushed-screen intakes can meet nuclear and desalination environmental regulations. • The advantages seen in this study are likely to exist at many other nuclear plants. [ABSTRACT FROM AUTHOR]

This paper is among the first to report on the full integration of basin-scale models that include projections of the demand and supply of water and energy for residential, commercial, industrial, and agricultural sector users. We link two widely used regional planning models that allow one to study the impact of rising climate variability on water and electricity use in Sacramento, California. Historic data combined with the current energy and water system configuration was used to assess the implications of changes in temperature and precipitation. Climate simulations suggest that electricity imports to the region would increase during hot dry spells, when regional power production is most constrained. In particular, regional imports of electricity would increase over 35 % in hot dry years, assuming a 4 °C increase in average temperature and a 25 % decrease in average precipitation. [ABSTRACT FROM AUTHOR]

Abstract: When algal blooms (such as red tide) occur, early detection of increased algal growth in intake water offers desalination plant operators advanced warning of severe fouling and provides the necessary time for preventative measures. Monitoring basic water quality measurements such as turbidity, silt density index (SDI), dissolved oxygen, and bulk fluorescence can approximate algal activity; however, these measurements lack the resolution needed to accurately track growth throughout all phases of a bloom event. This study investigates the use of a laser scanning cytometer (LSC) that detects algal cells over a wide range of concentrations (50–150,000cells/ml), and characterizes cell shape, size, and distribution parameters through fluorescence signal imaging. Water samples are filtered to collect algae on a 0.2-μm membrane surface. Sample volume is variable so cells can be concentrated. The membrane surface is scanned with a 635-nm diode laser and the signal is processed to generate a cell count and distribution image. LSC performance was comparable to fluorescence microscopy and flow cytometry over a range of concentrations that may be encountered during a bloom event. The applicability of LSC was demonstrated using laboratory-grown cultures and seawater samples taken during a bloom event off of the coast of Long Beach, CA. [Copyright &y& Elsevier]

Abstract: The technical feasibility of reverse osmosis (RO) desalination of agricultural drainage (AD) water in California''s San Joaquin Valley (SJV) was evaluated based on systematic analysis of water quality monitoring data and field water desalting tests in a laboratory plate-and-frame RO (PFRO) system. Thermodynamic solubility analysis and diagnostic PFRO desalting tests served to determine the feasible range of water recovery limits and to assess the mineral scaling potential. Analysis of the recovery limits imposed by scaling due to sparingly soluble salts (e.g. calcite, gypsum, silica) suggested feasible recoveries in the range of 46%–69%. Diagnostic PFRO desalting tests with five representative field water sources from the SJV (having gypsum and calcite saturation indices in the range of 0.12–1.03 and 2.9–9.5, respectively) confirmed the above recovery range. Mineral scale coverage was consistent with the observed flux decline. Deployment of RO technology for treatment of brackish SJV AD water would require site-specific process optimization given the geographic and temporal water quality variabilities. Therefore, RO operation with variable feed water quality (with respect to salinity and scaling propensity) and at sufficiently high recovery would require effective plant control, enabled by real-time mineral scale detection and adaptable process operation to mitigate mineral scaling. [Copyright &y& Elsevier]

Rapidly growing regions such as the western United States face difficult challenges in mobilizing new water supplies to meet new demands. Environmental concerns have curtailed the scope for large new surface storage projects, and widespread basin overdraft has limited ground water's potential as a source of expansion. Drawing on the California experience, this article explores modern water planning approaches, which focus on a portfolio of options including nontraditional sources (recycling, desalination, underground storage) and more efficient use of existing supplies (conservation and water marketing). It reviews the advantages and drawbacks of the elements of the portfolio, provides examples of innovative planning approaches, and assesses the role for supportive government policies. [ABSTRACT FROM AUTHOR]

The San Diego County Water Authority of California has initiated planning for coastal desalination facilities to augment their water supplies. Integration of the different water qualities from these facilities into existing pipelines must be achieved. This investigation determined whether, and to what degree, consumers can discriminate between desalinated seawater and imported water supplies and how these investigations can contribute to decision making regarding the need for construction of facilities to blend such supplies prior to delivery. Based upon the results of the flavour profile analysis panel and the consumer evaluation sessions, it was concluded that free chlorine versus chloramine disinfection or different concentrations of disinfectants did not significantly affect consumer perception of the taste and odour of desalinated seawater or blends with Colorado River water and State project water. Consumers were able to discern between desalinated seawater and imported water, preferring imported water when forced to make a choice. However, the investigators did not believe that the difference in consumer perception was significant enough to warrant special blending facilities to mitigate the relatively minor aesthetic quality differences between imported water supplies and desalinated seawater. [ABSTRACT FROM AUTHOR]

Saline-sodic (4 < EC[dS/m] < 30; 10 < SAR < 40) drainage water can be used to irrigate crops that are moderately sensitive, moderately tolerant and tolerant to salinity. However, in order to be sustainable, particular attention is required towards crop selection, control of soil salination, and crop and soil management to maintain soil permeability to water and air. Potential negative impacts of B, Mo and Se on crop yields, forage quality and wildlife also must be taken into account and, if necessary, mitigated. The focus of this paper is the California experience, along the Westside San Joaquin Valley (WSJV), related to these concerns. [ABSTRACT FROM AUTHOR]

Part I. Highlights the use of the brackish water desalination technologies for the Water Quality Improvement Program of the Port Hueneme Water Agency in California. Goals of the program; Timeline and cost of the program implementation; Information on the desalination demonstration facility.

Plummeting reserves and increasing demand of freshwater resources have culminated into a global water crisis. Desalination is a potential solution to mitigate the freshwater shortage. However, the process of desalination is expensive and energy-intensive. Due to the water-energy-climate nexus, there is an urgent need to provide sustainable low-cost electrical power for desalination that has the lowest impact on climate and related ecosystem challenges. For a large-scale reverse osmosis desalination plant, we have proposed the design and analysis of a photovoltaics and battery-based stand-alone direct current power network. The design methodology focusses on appropriate sizing, optimum tilt and temperature compensation techniques based on 10 years of irradiation data for the Carlsbad Desalination Plant in California, USA. A decision-tree approach is employed for ensuring hourly load-generation balance. The power flow analysis evaluates self-sufficient generation even during cloud cover contingencies. The primary goal of the proposed system is to maximize the utilization of generated photovoltaic power and battery energy storage with minimal conversions and transmission losses. The direct current based topology includes high-voltage transmission, on-the-spot local inversion, situational awareness and cyber security features. Lastly, economic feasibility of the proposed system is carried out for a plant lifetime of 30 years. The variable effect of utility-scale battery storage costs for 16–18 h of operation is studied. Our results show that the proposed design will provide low electricity costs ranging from 3.79 to 6.43 ¢/kWh depending on the debt rate. Without employing the concept of baseload electric power, photovoltaics and battery-based direct current power networks for large-scale desalination plants can achieve tremendous energy savings and cost reduction with negligible carbon footprint, thereby providing affordable water for all. [ABSTRACT FROM AUTHOR]

The article reports on the concept of the Groundwater Recovery and Treatment (GREAT) program, which was designed to manage community water resources as a fully functioning regional water supply system at Oxnard desalination facility in California. It relates that the program aims to reduce the need for imported water by creating facilities that can use brackish groundwater resources and reduce dependence on costly imported water supplies. Moreover, it emphasizes that GREAT is an energy-efficient treatment for brackish local groundwater, producing high-quality potable water that is blended with local groundwater for delivery to customers.

There is approximately 508.7 million cubic meters (3.2 million barrels) of oilfield-produced water generated per year across the oil fields of California. While less than 2% of this produced water receives advanced treatment for beneficial reuse, changing regulations and increasing scarcity of freshwater resources is expected to increase the demand for beneficial reuse. This paper reviews onshore-produced water quality across California, relevant standards and treatment objectives for beneficial reuse, identifies contaminants of concern, and treatment process design considerations. Lastly, we evaluate the capital and operating costs of an integrated membrane system for treating produced water based on data from a field pilot conducted in the coastal region of California. [ABSTRACT FROM AUTHOR]

Biwater Inc, which focuses on providing clean water and treating wastewater, has been awarded a contract covering equipment for a desalination facility in Southern California, USA that is being constructed to ensure a safe and reliable water supply for the region, and reduce the reliance on imported water. [ABSTRACT FROM AUTHOR]

Seawater reverse osmosis (SWRO) desalination is increasingly used as a technology for addressing shortages of freshwater supply and desalination plants are in operation or being planned world-wide and specifically in California, USA. However, the effects of continuous discharge of high-salinity brine into coastal environments are ill-constrained and in California are an issue of public debate. We collected in situ measurements of water chemistry and biological indicators in coastal waters (up to ~2 km from shore) before and after the newly constructed Carlsbad Desalination Plant (Carlsbad, CA, USA) began operations. A bottom water salinity anomaly indicates that the spatial footprint of the brine discharge plume extended about 600 m offshore with salinity up to 2.7 units above ambient (33.2). This exceeds the maximum salinity permitted for this location based on the California Ocean Plan (2015 Amendment to Water Quality Control Plan). However, no significant changes in the assessed biological indicators (benthic macrofauna, BOPA-index, brittle-star survival and growth) were observed at the discharge site. A model of mean ocean wave potential was used as an indicator of coastal mixing at Carlsbad Beach and at other locations in southern and central CA where desalination facilities are proposed. Our results indicated that to minimize environmental impacts discharge should target waters where a long history of anthropogenic activity has already compromised the natural setting. To ensure adequate mixing of the discharge brine desalination plants should be constructed at high-energy sites with sandy substrates, and discharge through diffusor systems. [ABSTRACT FROM AUTHOR]

Israel''s IDE Technologies Ltd has signed a contract with Kiewit Shea Desalination to design and supply equipment for the largest seawater desalination plant in the US, located in Carlsbad, California. [Copyright &y& Elsevier]

In the USA, global provider of environmental engineering, construction and strategic consulting services MWH has formed a partnership with the American Water Works Association Research Foundation (AwwaRF) and the California Energy Commission to develop a desalination research forum that aims to help address water supply issues. [Copyright &y& Elsevier]

The article discusses the move of governments and investors to consider desalination as a solution of the water supply shortage. Due to climate changes, increasing population and political concerns, leaders were urged to take a look at the process. In Australia, being the driest inhabited continent, protesters were complaining that the desalination facility can generate too much freshwater. The government-owned plant will produce over 300,000 cubic metres of drinkable water a day when it opens in 2011. Environmental groups believe the facility is not really important, though water consumption rose by 25%, there would be an excess of about 60%. In a related matter, there are also proposed desalination plants in California.

The article offers information on the development of a desalination facility in Carlsbad, California. It is posed that Poseidon Resources Corp. has selected the team which will engineer, design, commission, and construct a $270 million, 50-mgd seawater desalination plant in this location. The team involves Acciona Agua and its partners, PBS&J and J.R. Filanc Construction Co., and American Water. Moreover, Poseidon has been closely working with the City of Carlsbad since 1998 to develop this desalination facility.

Provides information on the Seawater Desalination and the California Coastal Act report by the California Coastal Commission. Outline of the report; Findings of the report.

In the USA, Long Beach, Los Angeles and the Federal Government, in an exclusive public sector partnership, are to build a 1.14-million-litre (300 000-gallon) per day prototype seawater desalination facility at the Haynes Generating Station. [Copyright &y& Elsevier]

The author investigates how to improve the reliability of municipal water supply in water-scarce, fast-growing regions such as southern California. Topics covered include two unconventional sources of municipal water in California which include toilet-tap sewage recycling and seawater desalination, reason the frequent occurrence of drought cause so much disruption of municipal water supplies, and unconventional ways to help meet dwindling municipal water supplies in water-scarce regions.