Facing Water Scarcity Research Articles

Impact of climate change on adaptive management decisions in the face of water scarcity

Reoccurring drought through the early 2000s has caused a serious water scarcity issue in the Colorado River Basin. Previous modeling studies have focused on the impact of climate change without considering the adaptive behaviors of farmers and under-utilized Indian water rights. In this paper, we use a coupled agent-based water resource model (ABM) to investigate how the adaptive decisions of farmers can affect water resource management under both climate change impacts and fully utilized Indian water right conditions. We used five General Circulation Model projections with RCP8.5 scenarios for the study. The results of farm-level decision-making showed different responses in irrigated areas that were changing due to climate change impact. While winter precipitation changes might partially explain the behavior changes, no specific pattern could be concluded based on their location. Also, farmers’ responses about annual water diversion showed more significant inter-year variation compared to irrigated areas. Basin-level metrics showed that climate change impacts will generally worsen water scarcity issues as measured in Navajo Reservoir storage, flow to Lake Powell, and instream flow requirement. But these basin-level water scarcity metrics cannot reflect individual farm-level impacts under climate change, which is why modeling the bottom-up management actions is necessary. When the under-utilized Indian water rights are fully used, it is more likely to trigger the shortage sharing agreement due to the higher tribal water depletion. Evaluation of model uncertainty and a more realistic setup for adaptive actions under drought contingency plans are suggested for future research.

Emergency Rainwater Harvesting, Water Storage, and Distribution System for an Affordable Housing Development in Barbados

Background: To sustain both permanent residents and an intense tourism industry, Barbados overpumps its sole source of natural freshwater—the aquifer. Climate change is projected to increase both storm intensity and drought, further hampering groundwater recharge. These intense rainfalls quickly saturate topsoil and result in extensive surface run-off that causes flooding, erosion, sedimentation, and eutrophication. By providing more water for households and reducing aquifer withdrawal, rainwater harvesting has the potential to both mitigate water scarcity and reduce the amount of harmful run-off. However, rainwater harvesting is not currently practiced in Barbados. This paper proposes a hurricane-resistant rainwater harvest, storage, and distribution system to be implemented in an affordable housing community in St. Thomas, Barbados.Methods: In the creation of the distribution system design, social, economic and environmental concepts need to be considered. We first conducted a field survey within the neighbourhood to understand what the residents felt the local water supply lacked. Afterwards, we performed a detailed rainfall analysis to determine the amount of rainwater that can realistically be captured. Finally, we consulted with various academic experts, local industry members, and supply stores to determine an affordable design.Results: Our findings suggest that an initial household investment of $2790.90 BBD appears adequate to provide a system for rainwater harvesting, dual plumbing, and communal distribution which can withstand and utilize 1/50 years storms.Limitations: Given that rainwater harvesting is not currently practiced in Barbados, government initiatives are needed to encourage its development.Conclusion: Affordable rainwater harvesting, dual plumbing, and community distribution systems can be implemented to possibly reshape life in countries facing water scarcity.

Chang approximation for the osmotic pressure of dilute to concentrated solutions

As many regions around the world are facing water scarcity, reverse osmosis (RO) has attracted attention to supply fresh water to such areas. To design and develop energy-efficient RO processes, accurate osmotic pressure values of salt water are critical, yet conventional models of osmotic pressure have significant deviations from the actual values. In addition, absence or high charge of authentic osmotic pressure databases prevents accessing authentic data. Here, we propose combining the Chang correction factor, a polynomial in solution concentration, with traditional osmotic pressure models to approximate the osmotic pressure of dilute to concentrated solutions with high accuracy. The Chang correction factor is determined by regressing a handful of authentic osmotic pressure data divided by theo- retical values calculated using traditional models. Multiplication of resulting polynomials back to corresponding tradi- tional models enables accurate approximation of the authentic osmotic pressure of dilute to concentrated solutions with R2 approaching 1. In addition, generality of the strategy over aqueous and organic solutions is demonstrated by approx- imating osmotic pressure of NaCl and sucrose aqueous solutions and C2H4Cl2-C6H6 and C3H6Br2-C2H4Br2 organic solutions. The approximation strategy proposed and assessed here will be useful to simulate and develop processes for seawater desalination and various industries with high importance.

Development of IoT-based water reduction system for improving clean water conservation

Water is one of the basic necessities of life; however, due to the increased growth of population and without any changes of people’s current water consumption rate the world would face water scarcity in the near future. Developing tools and techniques that aim to combat the loss of water quantity becomes a priority action due to it can provide actionable information to the community in its contribution to clean water conservation. In this study, the IoT-based water reduction system has been developed to measure water volume at three household appliances (washing machine, shower, and toilet) by installing flow sensors to those of each pipeline. Each sensor was connected to a microcontroller that sends water volume data and it will be stored in the cloud server. This technology could help users in reducing clean water consumption by: alarming user whenever water volume reaches 75, 85 and 95% of the limit volume for each showering session by installing a buzzer to the shower’s pipeline; limiting the water used for the toilet flushing by installing a solenoid valve for the toilets’ pipelines; and allowing users to access the information of all water consumption through Android-based mobile application. Through this study, IoT technology has great potential to support clean water reduction strategy due to it could save clean water up to 402 l monthly. Application of IoT technology can be started to be installed in such a small house or apartment in which the user can directly monitor their water consumption.

Hydrological consequences of natural rubber plantations in Southeast Asia

AbstractSince the turn of the century, rubber plantations have been expanding their footprint across Southeast Asia in response to an increasing global demand for rubber products. Between 2000 and 2014, the area cultivated with rubber more than doubled. It is not clear how this major change in the agricultural landscape of Southeast Asia, the main area of rubber production in the world, is affecting land‐use patterns and water resources in the region. Here we use maps of rubber plantations and other croplands in conjunction with a hydrological model and remote sensing analyses to assess land‐use patterns and water resources affected by natural rubber plantations. Results show water requirements of rubber trees are comparable to those of forests but by far exceed those of the other predominant crops and shrubland vegetation with the effect of potentially increasing water scarcity when rubber plantations replace these crops. The expansion of rubber plantations accounts for a 38 km3/yr increase in green water consumption, thereby exacerbating the monthly water scarcity, with an additional 2.4 million people and more than 0.6 Mha facing water scarcity in the driest months as a result of the increase in rubber production. Monthly runoff substantially decreases (by up to 25%) in 14% of the basins where rubber was planted. These results highlight the existence of major land use and hydrological impacts of agricultural development in Southeast Asia that affect the local environment and rural communities, calling for a more sustainable management of the limited land and water resources.

Urban water security: a comparative study of cities in the arid Americas

In this study we analyse how three cities in the arid Americas have addressed urban growth while facing water scarcity: Hermosillo, Mexico; Mendoza, Argentina; and Tucson, USA. We use the urban water security framework to examine five domains of water management: sociodemographic, economic, technological, ecological and governance (SETEG). Our analysis indicates that, in spite of water scarcity, urban growth has been promoted in the three cities. We argue that this expansion, although encouraged for economic development, is not sustainable in the long term. In the three cities, groundwater plays a major role in water supply, but growth has negatively affected riparian ecosystems, the health of the aquifers and access to domestic water. In order to pursue water security, several options are essential to enhance social–ecological system resilience. These include limits or reduction of urban expansion, reuse of treated effluent for riparian conservation, and community conservation efforts such as rainwater harvesting and other green infrastructure practices.

Facing Future Water Scarcity in the Duero-Douro Basin: Comparative Effect of Policy Measures on Irrigation Water Availability

AbstractThis study presents an analysis of possible policy measures to face water scarcity for agriculture in a long-term climate projection (2070–2100). Water availability was computed with the Wa...

EFFECT OF WATER SOURCES ON THE HEALTH OF RURAL CHILDREN: EVIDENCE FROM HOUSEHOLD SURVEY IN KWARA STATE, NIGERIA

Majority of the disease outbreak in developing countries have been attributed to contaminated water with children being the worst hit. Therefore, this study analyzed the effect of water sources on the health status of children under the age of 5 years in Ifelodun Local Government Area of Kwara State, Nigeria. Primary data was obtained through the use of semi-structured interviews; 150 households with at least one child under five years were interviewed however; only 146 questionnaires were completed and found valid for analysis. The data was subjected to descriptive statistics, such as pie chart, bar charts. The results show that majority (58.2%) of the children were males. Also, most (83.5%) of the children were infants, i.e. within the age range of 0-2 years. Most (96%) of the households had access to improved water sources of which protected dug well is the most accessible. Many (42%) of the households reported that they experience periods of water shortage, this explains why water washed diseases (disease associated with poor hygiene in the face of water scarcity) was the most predominant diseases reported among the children with 70 reported cases. These were closely followed by the water related insect vector diseases with 64 reported cases and then water borne diseases with 48 reported cases. Water based diseases rarely occurred in the study area. This study, therefore, recommends that effort should be geared towards provision of safe water all year round for the farming households. Also, insecticide treated nets should be made available for the children in the farming households so as to prevent insect bites.

Third pipe water recycling

Third pipe systems for recycled water are on the periphery of options for more resilient urban water management in the face of water scarcity. A number of schemes in the Australian water industry provide useful learnings. Even though direct supply costs are often higher than the potable water price, there are distinct circumstances where such schemes can be justified economically. Even where schemes have not been economic, there can be valuable lessons around the institutional alignment required to enable innovation for integrated urban water management.

Quality Testing of Air Conditioner Condensate and Its Potential in Water Conservation

A major part of world is facing water shortages today. While the world’s population has grown to more than 7.75 billion, the quantity of sweet water has remained the same. The ever increasing use of water by such a large population has resulted in pollution of many water sources. The developing world where a large fraction of total world population is located faces water scarcity in a more severe manner than the developed world. The developed world has managed to control human population and preserve natural water resources more effectively. As a result of this and also due to stabilized population, they face lesser problems for water availability. Indian population stands at 1.386 billion as nowadays. The erratic monsoon rains over last few years have resulted in floods and subsequent water shortages in summer months in major part of the country. A similar situation is faced by many Asian and African countries. The means of recycling and using every possible source of water are always welcome in these countries. Since many of these countries lie in tropical or semitropical zone, the average relative humidity is more than 50% for most of the year. Changing life styles in these countries and spread of information technology based sectors have resulted in a growth spurt in air conditioning facilities. An air conditioner draws heat from surrounding air and cools the premises to desired temperature. During this process, a large amount of moisture in the atmosphere gets condensed and is drained out. There are no efforts made to recover this water in India and neighbouring countries. We have undertaken studies to check the quality of this water and see the feasibility of its use in a decentralized but effective manner. The results show that this water condensate from air conditioners is highly pure, substantial and available almost round the year. This can help in recovering millions of litres of good quality water daily. This water would find uses in industries, laboratories, households and farming. It would also create good business opportunities.

Examine Design Considerations for Sustainable Management of an Overloaded Sewage Treatment Plant in a Residential Campus

The era is now facing water scarcity and the available water is being depleted at a faster rate to meet the needs of the growing population. At this juncture, it is essential to use the reduce-reuse-recycle strategy. Reducing excessive usage of water for essential needs and reusing the recycled water for non-consumptive purposes can be a great step in the conservation of water. The waste water from various sources can be collected and treated using an STP. In most of the cases, water treatment requires a centralized system of control and operation. The STP should be designed by considering the inflow characteristics, objective of the water treatment and availability of resources. There are various operational and managerial constraints while designing an STP. In case of overloaded condition of available STP, either some modification has to be done to prevent the decrease in efficiency of the obtained output or a new plant has to be constructed. In this case study, we have analyzed three different approaches to solve the issue of an overloaded STP. The results based on various criteria including cost of construction and maintenance have been discussed.

IoT-solar energy powered smart farm irrigation system

As the Internet of things (IoT) technology is evolving, distributed solar energy resources can be operated, monitored, and controlled remotely. The design of an IoT based solar energy system for smart irrigation is essential for regions around the world, which face water scarcity and power shortage. Thus, such a system is designed in this paper. The proposed system utilizes a single board system-on-a-chip controller (the controller hereafter), which has built-in WiFi connectivity, and connections to a solar cell to provide the required operating power. The controller reads the field soil moisture, humidity, and temperature sensors, and outputs appropriate actuation command signals to operate irrigation pumps. The controller also monitors the underground water level, which is essential to prevent the pump motors from burning due to the level in the water well. The proposed system has three modes of operations, i.e. the local control mode, mobile monitoring-control mode, and fuzzy logic-based control mode. For the purpose of the proposed system validation, a prototype was designed, built, and tested.

A substantial rise in the area and population affected by dryness in South Asia under 1.5 °C, 2.0 °C and 2.5 °C warmer worlds

Millions of people in South Asia face water scarcity every year. Previous studies based on the multi-model ensemble mean reported a decline in dryness (the ratio of potential evapotranspiration and precipitation) in South Asia under the warming climate. However, using observations and simulations from skilful climate models (BEST-GCMs) that simulate the critical monsoon features and show less bias to simulate observed climate, we show that dryness has significantly increased over the Gangetic Plain and parts of Pakistan during 1951–2016. Moreover, a rise in global mean temperature of 1.5 °C from the pre-industrial level will result in an increased dryness over half of South Asia affecting more than 790(±336) million people. Population affected by dryness is projected to 890 (±485) and 1960 (±1033) million under 2.0° and 2.5° warming worlds, respectively. Previously reported reduced aridity under the warming climate based on multi-model ensemble is mainly due to the GCMs that have less skill to simulate monsoon features. The GCMs with less skill project a higher increase (∼25%) in the monsoon season precipitation, which is largely due to their higher sensitivity of convective precipitation to warming. We show that the risk of water scarcity and dryness in South Asia under warming climate is higher than previously reported.

Modeling Hydrological Response to Climate Change in a Data-Scarce Glacierized High Mountain Astore Basin Using a Fully Distributed TOPKAPI Model

Water scarcity is influencing environmental and socio-economic development on a global scale. Pakistan is ranked third among the countries facing water scarcity. This situation is currently generating intra-provincial water disputes and could lead to transboundary water conflicts. This study assessed the future water resources of Astore basin under representative concentration pathways (RCP) 4.5 and 8.5 scenarios using fully distributed TOPographic Kinematic APproximation and Integration (TOPKAPI) model. TOPKAPI model was calibrated and validated over five years from 1999–2003 with a Nash coefficient ranging from 0.93–0.97. Towards the end of the 21st century, the air temperature of Astore will increase by 3°C and 9.6 °C under the RCP4.5 and 8.5 scenarios, respectively. The rise in air temperature can decrease the snow cover with Mann Kendall trend of –0.12%/yr and –0.39%/yr (p ≥ 0.05) while annual discharge projected to be increased 11% (p ≤ 0.05) and 37% (p ≥ 0.05) under RCP4.5 and RCP8.5, respectively. Moreover, the Astore basin showed a different pattern of seasonal shifts, as surface runoff in summer monsoon season declined further due to a reduction in precipitation. In the spring season, the earlier onset of snow and glacier melting increased the runoff due to high temperature, regardless of the decreasing trend of precipitation. This increased surface runoff from snow/glacier melt of Upper Indus Basin (UIB) can potentially be utilized to develop water policy and planning new water harvesting and storage structures, to reduce the risk of flooding.

From individual Fuzzy Cognitive Maps to Agent Based Models: Modeling multi-factorial and multi-stakeholder decision-making for water scarcity

Policy making for complex Social-Ecological Systems (SESs) is a multi-factorial and multi-stakeholder decision making process. Therefore, proper policy simulation in a SES should consider both the complex behavior of the system and the multi-stakeholders’ interventions into the system, which requires integrated methodological approaches. In this study, we simulate impacts of policy options on a farming community facing water scarcity in Rafsanjan, Iran, using an integrated modeling methodology combining an Agent Based Model (ABM) with Fuzzy Cognitive Mapping (FCM). First, the behavioral rules of farmers and the causal relations among environmental variables are captured with FCMs that are developed with both qualitative and quantitative data, i.e. farmers' knowledge and empirical data from studies. Then, an ABM is developed to model decisions and actions of farmers and simulate their impacts on overall groundwater use and emigration of farmers in this case study. Finally, the impacts of different policy options are simulated and compared with a baseline scenario. The results suggest that a policy of facilitating farmers' participation in management and control of their groundwater use leads to the highest reduction of groundwater use and would help to secure farmers’ activities in Rafsanjan. Our approach covers four main aspects that are crucial for policy simulation in SESs: 1) causal relationships, 2) feedback mechanisms, 3) social-spatial heterogeneity and 4) temporal dynamics. This approach is particularly useful for ex-ante policy options analysis.

Polyethylene Glycol Mediated Osmotic Stress Impacts on Growth and Biochemical Aspects of Wheat (Triticum aestivum L.)

Seed germination and seedling growth establishment are the most critical growth stages, and drought stress imposed at these stages highly limits crop productivity. In this regard, a hydroponic water culture experiment was conducted with the aim to assess the potential of 20 wheat genotypes against drought stress at the seedling stage. Water deficit was induced through polyethylene glycol (PEG-6000), by maintaining two osmotic potentials in water culture medium, i.e. −0.7 MPa (medium water stress) and −1.0 MPa (high water stress). After seed germination, drought stress was applied for 8 days. Seedlings shoot and root length and biomasses were restricted with an increase in osmotic deficit. Photosynthetic pigments and nitrate reductase activity (NRA) of wheat seedlings were reduced, while proline, total soluble sugars, total phenolics, and mineral ions (K+ and Ca2+) were augmented with the rise in water deficiency in most of the genotypes. On the basis of growth and biochemical attributes, six genotypes (NIA-AA-01, NIA-AA-08, NIA-AA-09, NIA-AA-13, NIA-AA-12, and NIA-AA-14) were categorized as drought tolerant, and three as medium tolerant. These genotypes exhibited better growth by showing the least reduction in root and shoot length, and fresh and dry biomasses, as well as modulation in biochemical processes to survive under water deficit. All studied traits indicated tolerance potential of these genotypes against moderate and extreme drought stress, which could also give better growth in arid and semi-arid regions of the country that facing water scarcity.

Multiple indices based drought analysis by using long term climatic variables over a part of Koel river basin, India

The present study demonstrates changes in vegetation pattern and climatic variability in past years in the parts of Koel basin in Jharkhand state of India by considering the spatial climatic variability, NDVI anomaly and satellite based drought indices viz Vegetation Condition Index (VCI), Temperature Condition Index (TCI) and Vegetation Health Index (VHI). Least square statistical method has been used for assessment of long term climatic fluctuation of major four climatic parameters viz maximum temperature of summer season, minimum temperature of winter season, rainfall of monsoon season, and solar radiation of Rabi and kharif season. Analysis of climate extremes has been done for 26 locations in the study area and then interpolated spatially in Geographical Information System platform. Long term NDVI anomaly shows adverse effect of climate extreme in past 20 years in the study area. The climatic variability exhibits that average maximum temperature during 1979–2017 fluctuates with an increase of 0.50–0.81 °C contrary to a decrease of 0.32–0.15 °C in various parts of study area. Similarly rainfall fluctuates with a decrease of 26–90 mm contrary to an increase of 19–230 mm. Drought prone zones as delineated from spatial overlaying map of VCI, TCI and VHI indicated value from 23 to 55. Major part of the study area severely affected by drought facing water scarcity and mediocre vegetation condition. These areas need proper planning and soil moisture management to overcome the recurrent drought conditions perceived in upcoming years.

Future Hot and Dry Years Worsen Nile Basin Water Scarcity Despite Projected Precipitation Increases

AbstractCompound extremes—particularly hot and dry years—can reduce crop yields and result in acute water scarcity. These risks are particularly pronounced in the Upper Nile Basin, a chronically water stressed agricultural region that includes western Ethiopia, South Sudan, and Uganda. While the causes of humanitarian crises in the Nile Basin are complex and involve governance, conflict, and climate, we demonstrate that nearly all recent regional crop failures have occurred amid hot and dry conditions and low runoff supplies. Using an observational ensemble, we find that such hot and dry years have been more frequent in recent decades, driven by increasing regional temperatures. This trend is likely to continue despite climate model projections of increasing regional precipitation. By the late 21st century, the frequency of hot and dry years may rise by a factor of 1.5–3, even if warming is limited to 2 °C. Regional water scarcity will continue to be a chronic issue for the Upper Nile from population growth alone, but runoff deficits during future hot and dry years will amplify this effect, leaving an additional 5–15% of the future population facing water scarcity. Climate change, along with the region's complex water politics, dependence on subsistence agriculture, and history of geopolitical instability, places the region at risk of severe food and water shortages as hot and dry years become more frequent. Adaptation and climate‐resilient water management policies informed by an understanding of compound extremes will be essential to manage these risks.

Avances y desafíos en el conocimiento de los bosques mesófilos de montaña de México

Los “bosques mesófilos de montaña” son ecosistemas que se caracterizan por el nivel de estratos arbóreos, abundantes helechos y epífitas. Actualmente esta formación vegetal se encuentra en forma de relictos en algunas de las cañadas del país, por lo que es importante conservar este ecosistema que ocupa menos de 1% del territorio nacional y que tiene un alto valor ante la escasez de agua y la pérdida de los bosques. Su importancia ecológica radica en la alta diversidad de flora y la presencia de especies endémicas en peligro de extinción que funcionan como cubierta protectora para evitar la erosión. Su importancia hidrológica deriva de la presencia de lluvias y nubosidad, neblina o niebla durante gran parte del año que reduce la incidencia de radiación solar disminuyendo las salidas de agua por evapotranspiración. Además, al ingreso de precipitación por lluvia hay que adicionar la precipitación horizontal de la niebla interceptada por el dosel. En este trabajo se presenta una revisión bibliográfica de los estudios realizados en México mediante búsquedas específicas y especializadas en buscadores académicos (Web of science, ScienceResearch, Academia.edu y Google scholar). Se encontró un alto índice de publicaciones de investigación ecológica en torno a la biodiversidad (fauna, listados florísticos y estructura de la vegetación), perturbación, sucesión secundaria, restauración ecológica; sin embrago, se identificaron un número limitado de trabajos sobre servicios ecosistémicos (hidrológicos y captura de carbono) y los más recientes están relacionados al cambio climático.

Spatio-Temporal Mapping of Water Consumption at Public Institutions: Case of the United Arab Emirates University

Abstract. The United Arab Emirates (UAE) faces water scarcity. Yet, the UAE is one of the highest countries in the per capita water consumption. The United Arab Emirates University (UAEU) is one of the biggest public institutions in the country. On average, the water costs the university annually around two million dirhams. In this study, indoor water consumption at the UAEU is assessed for the period 2016–2017. Geographic Information System (GIS) is utilized to answer where water is highly consumed within the university (hot spots), when (time), who consume it, why (causes), and how to minimize consumption. It assembles diverse data reside at various departments to gain a better knowledge about the broad patterns of water consumption in the university. The assumption made here is that water consumption is directly proportional to population density and less during winter. The highest water consumption is found at the College of Information Technology (CIT) and this is due to its size and heterogeneity of its activities. The relationship between water consumption and number of students is modeled using least square. The results indicated low correlation between water consumption and number of students. This may be due to the centralized usage of buildings and movement of students between buildings. Temporal variation showed sharp decrease during July of 2016 and 2017 irrespective of the building type/size and this is associated with summer holidays. The hypothesis of activity-driven consumption showed that the highest water consumption is found at residential buildings due to the longer stay time at hostels. The library showed consistent low water consumption. It is interesting to deduce the library usage while investigating water consumption, but it is a lesson that water consumption could be used as a proxy to reveal number of users at buildings. The water consumption at UAEU is benchmarked with other institutes in UAE and abroad. The result from this study identified sites with the highest water consumption and this could be used to adapt water conservation techniques at these sites. A survey was conducted to understand the students’ water consumption behavior, know their willingness to use water conservation methods, and measure their awareness level related to water issues in UAE. The results revealed that half of the respondents are not aware of the water issues. Majority of respondents prefer to drink bottled water than tap water. Majority of respondents are not willing to use grey water or urinals as ways to conserve water due to the lack of knowledge and some physiological reasons. Yet, they are willing to take course designed to teach them how to conserve water and to participate in competitions that reward them for having lower water consumption at hostels.