M3 Of Water Research Articles

Adoption of floating solar photovoltaics on waste water management system: a unique nexus of water-energy utilization, low-cost clean energy generation and water conservation

Scarcity of land coupled with rising land price is detrimental in developing large-scale solar photovoltaic (PV) power plants. A practical alternative is to develop floating solar photovoltaic (FSPV) systems, where the PV modules are floated on water. Technical assessment and feasibility study of FSPV systems are not well addressed. This paper presents the adoption of FSPV system on waste water treatment systems as large water surfaces are available. An experiment was performed to determine the performance of FSPV system in outdoor conditions, and it revealed that the FSPV module performed with 9.84% higher efficiency than land-based PV (LBPV) module. A feasibility study and techno-economic analysis of 15 MW FSPV system are presented and compared with a similar LBPV system. Results show that the FSPV plant will supply 26,465.7 MWh of energy annually to the grid and operate with performance ratio (PR) of 86.7%. The FSPV system will also save 7,884,000 m3 of water by reducing evaporation and the reduction in CO2 emission will be 518,943.4 tCO2. Financial analysis of the FSPV system reveals that the levelized cost of electricity (LCOE) is 0.047 $/kWh which is 7.84% lower than LBPV system. Comparison of the FSPV system and a similar LBPV system reveals that the social and economic performance of the FSPV system is better than the LBPV system. The results will help the policymakers in making conversant decisions toward developing FSPV projects and also help wastewater plants to shift toward sustainable practices.

Water management for Istanbul: collapse or survival

The study explored and discussed the water management strategy of Istanbul with more than 16 million inhabitants. Istanbul has quite limited local fresh water resources with an ultimate storage capacity of 868.7 million m3 and supplies daily approximately 2.8 million m3 of water at a magnitude of 180 L/ca. 36% of the water demand is supplied from a water source 190 km away from the city. In this study, the critical balance was evaluated accounting for all important factors, population, expansion; water demand; water quality; protection of water resources. The evaluation was specifically conducted in two major water catchment areas around Buyukcekmece and Omerli Basins between 1994 and 2019 using remote sensing technology. The results outlined a significant increase mainly from bare land and green area to artificial surface in Buyukcekmece and Omerli Basins with a rate of 217% and 77%, respectively. The conversions to artificial surface were mostly observed to occur in long-range protection zones in both basins. This study also interpreted the potential impacts of the proposed “Canal Project” on water resources regarding the existing and future demands of the population living in Istanbul. The quantitative and qualitative evaluations outlined the fact that the following 5 years of Istanbul will be a critical period in terms of survival and collapse of water management, and that Istanbul needs to enrich its local water resources by generating other alternatives, i.e. sea water desalination from Black Sea or Marmara Sea to compete with the increase of population.

Desain Kolam Retensi Berbantu Komputer di Cibuluh Kota Bogor

Water retention serves to control the surface runoff and conservation of rainwater in maintaining groundwater accumulation. This research aims to know the discharge of flood, know the volume of water to be accommodated in water retention, determine optimal water retention volume capacity, produce an effective design of water retention technical design, and produce a cost budget plan. Research conducted in Cibuluh Quarter, Tanah Baru Village, District Bogor Utara, Bogor City, West Java. Komulative flood discharge is 12.01 m3/sec. Capacity of Ciheuleut River is 9.38 m3/sec. Total capacity of water retention is 5272.52 m3. The Capacity development is 10481 m2. Water retention area that can be constructed is 4241 m2. The depth is 4 m so the capacity is 16964 m3. The structure is oval. The shortest diameter dimension is 50 m and the longest is 108 m. Total depth plan of 6 m is able to accommodate maximum 25446 m3 of water. Planned a type of sluice with width 1300 mm x height 1600 mm with a discharge of 4.89 m3/sec. It takes a total of 5 sluices on inlet and outlet. The cost required in the construction of Cibuluh Water Retention is Rp13.680.570.000,00.

Performance of a prototype windmill for water pumping in Kpakungu community of Niger State Nigeria

Water is the primary source of life for mankind and one of the most basic necessities for rural development. Most rural communities in Nigeria do not have access to potable water. This research considers the provision of water to a community in Nigeria using power from wind. The design results show that a 2.076m diameter windmill is required for pumping water from borehole through a total head of 45m to meet a daily demand of 3.5m3 of water. Performance test of the horizontal axis wind pump was carried out. The lowest measured wind speed during the test was 0.4 m/s, while the corresponding water discharge flowrate was 0.032 l/s. Thehighest flowrate of 0.113 l/s was recorded at a wind speed of 2.4 m/s. Computer simulation was carried out to validate the performance test of the prototype windmill. The results showed that water discharge is proportional to the wind speed.
 Keywords: Energy, Kpakungu, mean wind speed, plunger, windmill

Spatially variable hydrologic impact and biomass production tradeoffs associated with Eucalyptus (E. grandis) cultivation for biofuel production in Entre Rios, Argentina

AbstractClimate change and energy security promote using renewable sources of energy such as biofuels. High woody biomass production achieved from short‐rotation intensive plantations is a strategy that is increasing in many parts of the world. However, broad expansion of bioenergy feedstock production may have significant environmental consequences. This study investigates the watershed‐scale hydrological impacts of Eucalyptus (E. grandis) plantations for energy production in a humid subtropical watershed in Entre Rios province, Argentina. A Soil and Water Assessment Tool (SWAT) model was calibrated and validated for streamflow, leaf area index (LAI), and biomass production cycles. The model was used to simulate various Eucalyptus plantation scenarios that followed physically based rules for land use conversion (in various extents and locations in the watershed) to study hydrological effects, biomass production, and the green water footprint of energy production. SWAT simulations indicated that the most limiting factor for plant growth was shallow soils causing seasonal water stress. This resulted in a wide range of biomass productivity throughout the watershed. An optimization algorithm was developed to find the best location for Eucalyptus development regarding highest productivity with least water impact. E. grandis plantations had higher evapotranspiration rates compared to existing terrestrial land cover classes; therefore, intensive land use conversion to E. grandis caused a decline in streamflow, with January through March being the most affected months. October was the least‐affected month hydrologically, since high rainfall rates overcame the canopy interception and higher ET rates of E. grandis in this month. Results indicate that, on average, producing 1 kg of biomass in this region uses 0.8 m3 of water, and the green water footprint of producing 1 m3 fuel is approximately 2150 m3 water, or 57 m3 water per GJ of energy, which is lower than reported values for wood‐based ethanol, sugar cane ethanol, and soybean biodiesel.

What Can Radiation Protection Experts Contribute to the Issue of the Treated Water Stored in the Damaged Fukushima Daiichi Nuclear Power Plant?

Decommissioning efforts are underway at the reactor where the accident occurred, namely the damaged Tokyo Electric Power Company (TEPCO) Fukushima Daiichi Nuclear Power Plant (FDNPP). However, a large amount of groundwater flowing into the site has become contaminated with radioactive substances and is stored in tanks on site, which has hampered the decommissioning work. Although the inflow of groundwater has been greatly reduced through measures such as the construction of frost walls, approximately 170 m3 of water treated by the Advanced Liquid Processing System (ALPS) is being stored in tanks, each day. The tanks used to store this treated water are expected to become full by around the summer of 2022. It is not easy to get people to understand the efforts of all concerned parties, and providing clear information to these concerned parties is also a challenge. Questions have also been raised regarding whether other alternatives have been fully explored in the ALPS subcommittee. Some people have commented that the answers to the questions raised regarding the biological effects of tritium transmutation are inadequate. Some suspect that the answers are too detailed and incomprehensible, and that the respondents may be manipulating the public with some malicious intent. In any case, each possible plan presents both advantages and disadvantages, depending on the people who are involved. That makes it an ethical and vexing issue that can sway decisions, as perspectives change. While the environmental release plan is scientifically safe, it may represent a painful alternative. On the other hand, a more careful and imaginative approach to the idea of continued storage in tanks or other forms of storage may reveal some troublesome hidden disadvantages. Under these circumstances, experts must be prepared to answer people's questions in a comprehensive and robust manner.

Hydraulic assessment of a photovoltaic system driving a conventional AC surface electric pump

This paper presents a case study of a photovoltaic pumping system for irrigation and/or water storage purposes. To evaluate the efficiency of a photovoltaic water pumping system, hydraulic performance needs to be determined under solar irradiance available. Performance ratio (PR) was used to determine the hydraulic performance of a photovoltaic pumping system, operated by a variable frequency inverter coupled to a conventional alternating current surface pump. For days with solar irradiance above 7.3 peak sun hours (PSH), the system could operate more than 5 h with pressures over 4.7 bar and pump a volume over 45 m3 of water per day. For days with low solar irradiance, below 3 PSH, the system pumped up to 8 m3 of water with pressure over 4.1 bar. The results obtained confirm that this kind of PV system is valid option of power for water pumping for irrigation or storage systems. This can benefit small farmers in areas without power grid or those who wish to incorporate photovoltaic energy into an existing conventional pumping system.

Seismicity during and after stimulation of a 6.1 km deep enhanced geothermal system in Helsinki, Finland

Abstract. In this study, we present a high-resolution dataset of seismicity framing the stimulation campaign of a 6.1 km deep enhanced geothermal system (EGS) in the Helsinki suburban area and discuss the complexity of fracture network development. Within the St1 Deep Heat project, 18 160 m3 of water was injected over 49 d in summer 2018. The seismicity was monitored by a seismic network of near-surface borehole sensors framing the EGS site in combination with a multi-level geophone array located at ≥ 2 km of depth. We expand the original catalog of Kwiatek et al. (2019), including detected seismic events and earthquakes that occurred 2 months after the end of injection, totaling 61 163 events. We relocated events of the catalog with moment magnitudes between Mw −0.5 and Mw 1.9 using the double-difference technique and a new velocity model derived from a post-stimulation vertical seismic profiling (VSP) campaign. The analysis of the fault network development at a reservoir depth of 4.5–7 km is one primary focus of this study. To achieve this, we investigate 191 focal mechanisms of the induced seismicity using a cross-correlation-based technique. Our results indicate that seismicity occurred in three spatially separated clusters centered around the injection well. We observe a spatiotemporal migration of the seismicity during the stimulation starting from the injection well in the northwest–southeast (NW–SE) direction and in the northeast (NE) direction towards greater depth. The spatial evolution of the cumulative seismic moment, the distribution of events with Mw≥1, and the fault plane orientations of focal mechanisms indicate an active network of at least three NW–SE- to NNW–SSE-oriented permeable zones, which is interpreted to be responsible for the migration of seismic activity away from the injection well. Fault plane solutions of the best-constrained focal mechanisms and results for the local stress field orientation indicate a reverse faulting regime and suggest that seismic slip occurred on a sub-parallel network of pre-existing weak fractures favorably oriented with the stress field, striking NNW–SEE with a dip of 45∘ ENE parallel to the injection well.

Modelling payments for ecosystem services for solving future water conflicts at spatial scales: The Okavango River Basin example

This study aims to resolve a potential water conflict between the upper catchment communities of the Okavango River Basin and the downward communities in the Okavango Delta. A model to payment for ecosystem services is developed at the basin level, recognizing spatial diversity and water flows. It addresses four objectives: (1) To assess relationships between water consumption and land use from a spatial perspective. (2) To estimate water availability under current land use as a reference without any water policy intervention. (3) To optimize water flow generation as intended for getting ecosystem services. This is based on the mechanism of payments for ecosystem services, specifically in terms of land use change as stewardship. (4) To compensate farmers for economic losses due to upstream land use changes. Our study suggests that an integrated basin management should consider payments for ecosystem services to incentivize forest conservation. The annual payments of US$28.7 million could encourage farmers upstream to change their land uses from deforestation to forest conservation. With compensation, approximately 8.7 million hectares of Miombo forests would be maintained in the basin, which would secure 3656 million m3 of water during the rainy season and subsequently benefit the Delta in the dry season.

Evaluation of water productivity with three rice genotypes under different irrigation regimes and nitrogen fertilizer treatments in Rasht, northern Iran*

AbstractThis study investigates the water productivity of three rice genotypes in physical, economic and virtual water terms through different irrigation and fertilizer treatments. The experiment was conducted in 2017 and 2018 in split plot designs based on a randomized complete block design with three replications. The main factors include irrigation regimes: flood irrigation of I1 and alternate irrigation treatments of I2, I3 and I4 that involve alternate irrigation with irrigation intervals of 7, 14 and 21 days, respectively. The subfactors include different rice genotypes at three levels of certified local Hashemi, M5 and M12 genotypes at three levels of nitrogen fertilizer of 60, 80 and 100 kg N/ha1. Results showed that the certified Hashemi variety with the 7‐day irrigation interval and 100 kg N/ha1; treatment showed satisfactory physical water productivity (being 1.41 and 1.01 kg/m3 in 2017 and 2018, respectively), and also the highest net benefit per drop (being 31 200 and 29 800 rials/m3 in 2017 and 2018, respectively). According to the results of this study, using alternate irrigation at the 7‐day irrigation interval would save 285 million m3 of water in the Sefidroud irrigation and drainage network.

Campus Study of the Impact of Ultra-Low Flush Toilets on Sewerage Networks and Water Usage

Water demand management often focuses on quantifying the benefits of water efficiency rather than the potential impact of reduced flows on the sewer network. This study assessed the impact of a high-density deployment of ultra-low flush toilets (ULFT). A pre-installation washroom survey was carried out in July 2018. Water demand and sewer network condition were assessed ahead of the installation of 119 ULFTs and a real-time monitoring system across seven buildings on the University of Exeter campus. ULFTs were flushed 257,925 times in 177 days saving an estimated 2287 m3 per annum (compared to traditional 6 litre WCs). The annual cost saving of this reduction is approximately £12,580/annum, assuming a volumetric cost of £5.50/m3 of water. Mean discharge to the sewer network reduced by 6 m3/day. In the six-month period, 95 maintenance issues were reported, equating to 1 in 2700 flushes (0.037%). However, the frequency of incidents decreased after an initial commissioning period. There is no evidence, from blockage reports or photographs of manhole flow conditions, that the risk of blockage in the sewer network increased as a result of the ULFT installation programme.

Erosion, deposition and contamination by high‐magnitude subaqueous debris flows and turbidity currents: Insights from the failure of a tailings dam near Quesnel Lake, British Columbia

AbstractThe 4 August 2014 failure of Mount Polley mine tailings dam in central British Columbia, Canada, is the worst environmental disaster in British Columbia history. Around 25 million m3 of water, tailings solids and dam construction materials travelled as a slurry flow down nearby Hazeltine Creek. About 18.6 million m3 of tailings and displaced coarse sediment entered into the narrow, deep, fjord‐like Quesnel Lake. Multibeam echosounding, sub‐bottom profiling, sediment cores and theoretical models are used to examine erosion and deposition on the Hazeltine Creek fan‐delta and the bed of Quesnel Lake by subaqueous sediment density flows generated from the slurry. Strong to very strong subaqueous debris flows eroded two deep subaqueous channels on the fan‐delta in a period of less than 12 h. A model for subaerial debris‐flow erosion overestimates submerged delta‐front erosion rates in the channels because of evolution of the subaqueous debris flows and incomplete liquefaction of the eroding bed. The debris flows deposited a localized debrite with a hummocky surface composed of fine tailings and coarse displaced fan‐delta and fluvial sediment. A flat, featureless, surface composed of fine‐grained sediment adjacent to the debrite is interpreted as debrite/turbidite resulting from debris flows proximally and turbidity currents distally. Copper concentrations in cores are highly elevated compared to background concentrations in pre‐event native lacustrine sediment. Deposits from subaqueous sediment flows generated by earthquakes and glacial lake outburst floods are generally thinner than those in Quesnel Lake caused by the tailings dam failure.

Investigation on floating photovoltaic covering system in rural Indian reservoir to minimize evaporation loss

ABSTRACT The emerging floating photovoltaic (FPV) technology is the recent global attention in solar power production due to its high efficiency. Apart from the standalone FPV systems, hybridising the FPV system with the hydroelectric power plants (HEPP) will aid in increasing the power generation from HEPP by reducing the water loss through evaporation. In this study, the power generation and water-saving capacity of a model FPV system with various tilt angles, orientation and tracking mechanisms are analysed by covering 30% of the total area of Vaigai reservoir in India. The study shows that the proposed FPV plant with capacity of 1.14 MW generates 1.9 GWh of energy at its optimum tilt angle while saving 42,731.56 m3 of water annually. Further, cost analysis and carbon footprint estimation are also carried out. The results show that the FPV system will have a positive impact on the environment by saving 44,734.62 tons of CO2.

Virtual water flow associated with interprovincial coal transfer in China: Impacts and suggestions for mitigation

Abstract As the largest producer of coal in the world, China faces tremendous pressure to balance the expanding coal industry and water shortage. Tracking the movement of coal and the corresponding virtual water flow and analyzing their interdependencies are, therefore, essential for the synergetic management of the two resources. In this study, a novel assessment model that combines the concepts of water footprint and virtual water was proposed to quantify the virtual water flow associated with interprovincial coal transfer in China. The operating data of all coal mines and interprovincial coal trade data across the country in 2016 were incorporated into the analysis. It is estimated that there is considerable variation in the water consumption intensities of coal production and virtual water intensities of coal transfer among the provinces. A major part of the water footprint of coal production for China amounting to 4984 million m3 is concentrated in water-stressed north China; interprovincial coal trade involves the transfer of 2373 million m3 of water in virtual form, largely from water-scarce provinces to water-rich ones. With the expansion of the coal industry, the virtual water flow is expected to become 2669 million m3 by 2020, which will further exacerbate the spatial imbalance in water resources. However, virtual water flow can be reduced through optimizing coal transfer and improving water conservation by 458 million m3 and 281 million m3, respectively. The results of this study provide comprehensive insights into the nexus of coal and water. Suggestions regarding relieving the pressure on water for coal production in water-scarce provinces and rectifying the imbalance in virtual water flow due to the interprovincial coal trade are proposed to provide inputs for managers to optimize water quotas, formulate compensation mechanisms, and develop sustainable development policies.

Quantitative identification of water consumption in electricity development in 2017 in China

This paper takes each province and region as the research object and 2017 as the research period, and the water consumption of power production was analyzed. The results showed that China’s electricity production consumed 6.57 billion m³ of water, accounting for 2% of the total social water consumption in 2017. Thermal power is the most water-consuming power source in China, accounting for 78% of the total water consumption in the country’s electric power development. Based on the calculated results, this study also puts forward relevant suggestions for realizing energy-water coordinated security.

Designing an irrigation system using photovoltaic energy by considering crop type in Fergana Valley

Today, the importance of energy cost and efficiency is gradually increase. The decrease in drinking water and agricultural water resources, increases the interest in drip irrigation systems in agricultural irrigation. Environmentally friendly photovoltaic drip irrigation systems (PVDIS) are the appropriate solution in regions where there is no electricity distribution network, where it is far away, or where power cuts are frequently. This study is carried out in the Fergana Valley of Uzbekistan. Regional climate data obtained from Climwat 2.0 software are processed in Cropwat 8.0 software. Crops that are both the source of livelihood of the people of the region and that can be used in this study have been determined. Annual and daily water needs are analyzed so that these crops are irrigated every seven days. A system is designed by taking the data of the crop with the highest water requirement as a reference. The drip irrigation system is set up in a PVsyst 7.1.7 simulation environment to pump 114.24 m3 of water daily from a 5-meter-deep river with a 1.8 kW photovoltaic system. The efficiency of the system is 58.7% and the efficiency of the pump is 34.5%. Crop water need is met at the rate of 98.87%. It is predicted that the designed and analyzed PVDIS will provide efficiency in energy and water resources.

СУЧАСНІ ПРОБЛЕМИ ВОДОКОРИСТУВАННЯ В КОНТЕКСТІ ПАРАДИГМИ СТАЛОГО РОЗВИТКУ

The dominant concept of sustainable development in the modern world, which provides for the harmonization of economic, social and environmental components, raises the issue of rational use of all types of natural resources and environmental com-ponents. In this context, the issues of rational water use need special attention for Ukraine. This attention is due to a combina-tion of two aspects: on the one hand, water resources are widely used in social production and to meet the household needs of the population, and on the other -Ukraine is characterized by low water resources potential. The purpose of this study is to con-sider the current state of water use in Ukraine from the standpoint of the concept of sustainable development.The paper finds that the dynamics of intake, use and sewerage over the past thirty years is characterized by a general downward trend, which indicates the presence of positive changes in the fieldof water use in Ukraine. The general tendency to reduce water intake is described by the power function, which indicates that the elasticity of water intake from natural objects over time is -0.68%. The study assessed the effectiveness of water resources through the water content of GDP found that for the production of products worth a thousand dollars in Ukraine in 2019 consumed an average of 18.9 m3of water, which far exceeds the characteristics of most economically and technologically advanced countries. In the work on the basis of stochastic factor analysis the model of volumes of return water discharge is calculated, which shows that an increase of one percent of the population leads to an increase in return water discharge by 1.17%, and a percentage increase in industrial production will increase the return discharge by 0.65%.The performed analysis allows us to state that the general efforts in the field of water consumption in Ukraine have a positive vector of orientation, but in the absence of a radical change in the technological base of national production to achieve the goals of sustainable development will not succeed

Systematic Analysis Reveals Thermal Separations Are Not Necessarily Most Energy Intensive

Summary At the industrial level, separation of a variety of mixtures is predominantly carried out by thermally driven processes such as distillation. Nevertheless, the current literature seems to suggest that much is to be gained by replacing these processes with alternative non-thermal methods, which will potentially require a fraction of the energy used by distillation. This is primarily due to the widespread perception that thermal separation processes, particularly those that involve vaporization, are highly energy intensive. However, this belief is not well founded, because it is based on extrapolation from comparisons in the literature, many of which make ad-hoc assumptions and result in incorrect conclusions. Our analysis shows that this confusion arises because the processes utilize different types of energy: heat and electricity. Here, we present a consistent framework that enables a fair comparison between different processes that consume different forms of energies. Using this framework, we refute the general perception that thermal separation processes are inherently the most energy intensive and conclusively show through the examples of two challenging mixtures constituting components with low relative volatilities, that distillation processes, when run properly, can consume remarkably lower fuel than non-thermal membrane alternatives, which have often been touted as more energy efficient.

Economic Design of Solar-Driven Membrane Distillation Systems for Desalination

Solar-driven membrane distillation (SDMD) for desalination is a feasible method to solve water and energy resource issues. The design and operation of SDMD is different from continuous and steady state processes, such as common chemical plants, due to the intermittent and unpredictive characteristics of solar radiation. Employing the steady state and dynamic simulation models developed on the platform of Aspen Custom Modeler®, this paper presents a two-stage design approach for the SDMD systems using different types of membrane distillation configurations, including AGMD (air gap MD), DCMD (direct contract MD) and VMD (vacuum MD). The first design stage uses the steady state simulation model and determines equipment sizes for different constant-value solar radiation intensities with the objective of minimizing total annual cost. The second design stage is implemented on the SDMD systems with process control to automatically adjust the operating flow rates using the dynamic simulation model. Operated with the yearly solar radiation intensity of Taiwan, the unit production costs (UPCs) of the optimal SDMD systems using AGMD, DCMD, and VMD are $2.71, 5.38, and 10.41 per m3 of water produced, respectively. When the membrane unit cost is decreased from $90/m2 to $36/m2, the UPC of the optimal solar-driven AGMD system can be reduced from $2.71/m3 to $2.04/m3.

State of aggregations and biological characteristics for mysid Neomysis awatschensis in the northern Amur Bay (Peter the Great Bay, Japan Sea)

Size and sex structure of estuarine-freshwater mysid Neomysis awatschensis in the northern Amur Bay is considered, time of their aggregations formation is determined, and their biomass is estimated on the data of surveys conducted in 2014–2019. The samples were collected at the depth of 0.5–2.0 m in the daytime in May-July. The catches were recalculated per 1 m3 of water. All collected mysids (2212 ind.) were measured under binocular microscope with accuracy of 0.1 mm, weighted by torsion scales with accuracy of 1 mg, and separated to males, females and juveniles. The females were differentiated by 5 stages of their development: 1) immature females with oostegetic rudiments; 2) oviparous females; 3) females with embryos in the marsupia bags without stalk-eyes with black pigment; 4) females with embryos in marsupia bags with black eyes; 5) spawned females with empty marsupii. Time and duration of N. awatschensis aggregating changed by years in dependence on hydrological and weather conditions; the aggregations were either monospecific or mixed with another mysid species — N. mirabilis. The maximum mysid biomass could exceed 500 g/m3 that was appropriate for commercial fishery. The maximum body length of mysid females was 13.7 mm, of males — 12.0 mm. The average length varied from 6.7 to 10.3 mm, being shorter in summer months than in May. Portion of males in the aggregations was always significant (16.3–50.7 %), portion of females varied from 8.7 to 52.5 %, portion of juveniles was the largest in June (29.9–75.0 %). The females to males ratio was 1 : 1 in May and July of 2014–2017, but males prevailed in June 2015 (1.0 : 1.9), whereas females prevailed in June 2016 (1.8 : 1.0). Spawning of the mysids was the most intensive in May-June, though females had embryos at different stages of development in all samples that indicated an extended period of reproduction.