Additional Water Resources Research Articles

Technical Note: Integrated Surface-Groundwater Analysis for the Pyoseon Region, Jeju Island in Korea

In the Jeju Island (Republic of Korea), surface runoff characteristics are very different from those of the inland. Most streams dry up shortly after rainfall events due to the rapid recharge of deep aquifers through highly permeable volcanic basalt rock. For this reason, accurate estimation of hydrologic components is challenging even with up-to-date watershed models like the Soil and Water Assessment Tool (SWAT). Fortunately, the integrated SWAT-MODFLOW model is capable of simulating complex hydrologic phenomena including stream-aquifer interaction and spatiotemporal groundwater recharge. The integrated SWAT-MODFLOW model was applied for the comprehensive investigation of the hydrologic components of the Pyoseon region in the Jeju Island. The SWAT-MODFLOW model simulated water budget components reasonably well compared with observed data. The pumping module in the SWAT-MODFLOW model, which combines the well package of MODFLOW with SWAT's water transfer options, was used to simulate water pumping from the present 198 wells on the island by increasing pumping amounts up to 20-fold relative to the current pumping amount in order investigate the impact on hydrologic components. When groundwater pumping rate increases by 10- and 20-fold, then the groundwater discharge amount decreases 5.5% and 17%, respectively. Considering topographical characteristics of the island, most of recharged groundwater is shown to be discharged to the sea. Thus, appropriate groundwater extraction in the Jeju Island could reduce the loss of deep aquifer into the sea and subsequently be effective in securing additional water resources.

Sand Water Storage: Unconventional Methods to Freshwater Augmentation in Isolated Rural Communities of South Africa

South Africa water resources are scarce in global terms with mean annual rainfall about half world average of 860mm a year. On the other hand, current economy development with resulting contamination of available water resources will further reduced water availability if present patterns of water use continue unchanged. The conventional water resources (largely surface water) in the country have been fully exploited with little opportunity for further expansion. So therefore, new approaches are necessary by accessing alluvial aquifers of non-perennial rivers in forming additional water resources in this part of semi-arid region. High evaporative losses from surface storage, increasing costs of large dams and aridity conditions have hindered development of conventional water resources with increasing interest in using groundwater for rural water supply. Many of South Africa rivers are non-perennial therefore; development of unconventional sand water storage is appealing for freshwater augmentation in isolated rural communities. This paper presents overviews of South Africa water resources highlighting sand water storage options for potential application in rural water supply for isolated communities where groundwater potential is low.

Ameliorating water crises through sustainable wastewater reuse in Hengshui, China

Wastewater recycling and reuse systems are commonly used to ameliorate water crises and could provide additional water resources as well as reduce or eliminate pollution. Given the economic difficulties of sustaining operations, however, a cost‐effective wastewater reclamation system is critically important. A wastewater reclamation system was designed for the Taocheng District of Hengshui, China, a region suffering both a water crisis and financial difficulties. The project incorporates a sewage treatment plant, natural waterways, and a constructed wetland, all designed with careful consideration of local hydrologic and geographic conditions. The authors address the system—s role in guaranteeing effluent quality and quantity and the estimated anticipated benefits—including those from accompanying land‐use changes—that serve to offset operational expenses. The authors believe that when cost‐benefit considerations are taken into account, the wastewater reclamation proposal described here represents a viable and feasible project that offers a sustainable solution to China—s water crisis.

Improvement potential of the integrated water resources management in the mining basin of Gafsa

The phosphate mining basin of Gafsa is part of the south-western dry area of Tunisia. It covers 3250 km2, representing 42% of the entire governorate of Gafsa area and 38% of its total population. The area is characterised by water resources scarcity as well as high variability of rainfall. The water demand is in continual increase due to many factors such as the industrial, agricultural and socio-economic development.The confrontation between available resources and water demand for all sectors in the phosphate basin shows that the current global balance is in surplus.Taking into account the fact that all the sectors have neither the same requirement of water quality nor the same added value of the pumped water, it seems then necessary to review the current resources allowance model in order to establish rational exploitation plans so as to face the water demand increase.In the local context of the Gafsa phosphate mining basin, the treated waste water seems to constitute potential additional water resource that should be considered to reduce the groundwater resources overexploitation.

Alternative water resources in granitic rock: a case study from Kinmen Island, Taiwan

Kinmen Island is a small, tectonically stable, granitic island that has been suffering from a scarcity of fresh water resources due to excessive annual evapotranspiration over annual precipitation. Recent studies further indicate that shallow (0–70 m) sedimentary aquifers, the major sources of groundwater supply, have already been over-exploited. Therefore, this preliminary study is to investigate the existence of exploitable water resources that can balance the shortage of fresh water on this island. Site characterization data are obtained from island-wide geophysical surveys as well as small-scale tests performed in a study area formed by three deep (maximum depth to 560 m) vertical boreholes installed in mid-east Kinmen northeast to Taiwu Mountain. Vertical fracture frequency data indicate that the rock body is fractured with a spatially correlated pattern, from which three major fracture zones (depths 0–70, 330–360, and below 450 m) can be identified. Geologic investigations indicate that the deepest fracture zone is caused by the large-scale, steeply dipping Taiwushan fault. This fault may have caused a laterally extensive low-resistivity zone, a potential fractured aquifer, near Taiwu Mountain. The middle fracture zone is induced by the Taiwushan fault and intersects the fault approximately 21 m southeast of the study area below a depth of 350 m. Slug testing results yield fracture transmissivity varying from 4.8 × 10−7 to 2.2 × 10−4 m2/s. Cross-hole tests have confirmed that hydraulic connectivity of the deeper rock body is controlled by the Taiwushan fault and the middle fracture zone. This connectivity may extend vertically to the sedimentary aquifers through high-angle joint sets. Despite the presence of a flow barrier formed by doleritic dike at about 300 m depth, the existence of fresh as well as meteoric water in the deeper rock body manifests that certain flow paths must exist through which the deeper fractured aquifers can be connected to the upper rock body. Therefore, groundwater stored within the Taiwushan fault and the associated low-resistivity zone can be considered as additional fresh water resources for future exploitation.

Selecting Material for Large-Scale Seawater Desalination Facilities: Australia and U.S. Experiences

The need for additional water resources by many water utilities and a corresponding interest in brackish water and seawater desalination necessitates new materials and equipment to treat more corrosive waters, such as brackish water, raw seawater, reverse osmosis permeate, and membrane concentrate. This article focuses on seawater applications and highlights approaches taken by agencies in Australia and the United States to maximize long-term value of components of their large-scale seawater desalination facilities. This includes examining material selection and compatibility issues that develop during design, construction, and operation, as well as how these issues were mitigated. It is also important to evaluate the impact of specialized materials on equipment availability and maintenance and to help engineers and utilities understand key material compatibility and material supply issues associated with constructing a seawater desalination facility.

Irrigation of olive groves in Southern Italy with treated municipal wastewater: Effects on microbiological quality of soil and fruits

The use of municipal wastewater in agriculture requires a careful monitoring of a range of hygiene parameters. Yearly hygienic impact assessments on soil and fruit were made between 2000 and 2006 in an olive ( Olea europaea L.) grove established near a municipal wastewater treatment plant in Southern Italy (Ferrandina–Basilicata region, 40°29′ N, 16°28′ E). The experimental grove was managed in two plots. The first plot, non-tilled, was drip irrigated daily with reclaimed wastewater. The second plot was unirrigated (i.e. rainfed) and subject to conventional management for the region. Samples of wetted soil from different depths and of treated wastewater were analysed for Escherichia coli, enterococci, sulphite-reducing Clostridium spores and Salmonella spp. Fruits were collected both from the canopy and from nets spread on the ground and analysed for faecal contamination. The average annual quantity of wastewater distributed was 293 mm. E. coli concentration in the wastewater varied considerably, being frequently above the stringent Italian mandatory limit of 10 CFU 100 mL −1 and also the WHO limit of 1000 MPN 100 mL −1. Salmonella was never detected in the wastewater, the soil or on the fruit samples. Slight increases in the other bacteria were observed in the wastewater-irrigated soil during the irrigation season and especially in the top 10 cm. Soil resilience and bacterial mortality/inactivation probably explains the seasonal decrease of soil bacteria content over the 7 years of the study. Because of their high resistance to disinfection treatments and to environmental conditions, the spores of the sulphite-reducing bacterium Clostridium could be useful as an indicator of contamination in future guidelines that might be enacted for the use of wastewater in agriculture. No significant microbial contamination was recorded on fruit harvested directly from the canopy of the wastewater-irrigated trees. Contaminations on fruits sampled from the ground in the wastewater-irrigated plot were always low and usually similar to, or lower than those observed on drupes collected from the rainfed plot. In the rainfed plot, the recorded occasional contaminations were probably due to a number of factors, such as grazing of farm stock, presence of wild animals and surface water runoff from adjacent agricultural areas. This work confirms that, under suitable conditions, low-quality wastewater can be useful as an additional water resource for olive irrigation in water-scarce Mediterranean environments.

The water reclamation and reuse project of El Prat de Llobregat, Barcelona, Spain

Water reclamation and reuse have become essential components of water resources management in the Metropolitan Area of Barcelona, by helping to develop additional water resources in the lower Llobregat River, one of its main sources of water supply. By generating a reliable flow of 300,000 m3/day of high quality reclaimed water, the options available for integrated water resources management have widely expanded to allow in-stream river water substitution, restoration of natural wetland areas, agricultural irrigation, and supply to a seawater intrusion barrier. Those management options have been possible thanks to the implementation of an extensive water distribution system that allows distribution of reclaimed water to a point 15 km upstream of the reclamation facility, and to a seawater intrusion barrier within a few kilometres of the plant. The cost of producing reclaimed water using a physico-chemical process (0.05 euro/m3) and the investment required for such a facility (0.21 euro/m3 annual capacity) are very close to those of similar large scale projects in Spain. However, higher degrees of treatment, such as demineralization for agricultural irrigation and for injection into a seawater intrusion barrier, result in considerable increases of both water reclamation cost and investment costs.

Potential water supply of a small reservoir and alluvial aquifer system in southern Zimbabwe

Groundwater use by accessing alluvial aquifers of non-perennial rivers can be an important additional water resource in the semi-arid region of southern Zimbabwe. The research objective of the study was to calculate the potential water supply for the upper-Mnyabezi catchment under current conditions and after implementation of two storage capacity measures. These measures are heightening the spillway of the ‘Mnyabezi 27’ dam and constructing a sand storage dam in the alluvial aquifer of the Mnyabezi River. The upper-Mnyabezi catchment covers approximately 22 km 2 and is a tributary of the Thuli River in southern Zimbabwe. Three coupled models are used to simulate the hydrological processes in the Mnyabezi catchment. The first is a rainfall-runoff model, based on the SCS-method. The second is a spreadsheet-based model of the water balance of the reservoir. The third is the finite difference groundwater model MODFLOW used to simulate the water balance of the alluvial aquifer. The potential water supply in the Mnyabezi catchment under current conditions ranges from 2107 m 3 (5.7 months) in a dry year to 3162 m 3 (8.7 months) in a wet year. The maximum period of water supply after implementation of the storage capacity measures in a dry year is 2776 m 3 (8.4 months) and in a wet year the amount is 3617 m 3 (10.8 months). The sand storage dam can only be used as an additional water resource, because the storage capacity of the alluvial aquifer is small. However, when an ephemeral river is underlain by a larger alluvial aquifer, a sand storage dam is a promising way of water supply for smallholder farmers in southern Zimbabwe.

The Jordan River Basin: 2. Potential Future Allocations to the Co-riparians

The Jordan River drains parts of four States and one territory (Lebanon, Syria, Israel, Jordan and Palestine), and is an important regional source of water. A previous paper in this series discussed the flow allocations from the Jordan River to the co-riparians which were proposed in the Johnston Plan of 1955, noting that recently declassified documents shed new light on the allocation proposed for Israel. The present paper discusses potential future allocations of water from the Jordan River basin to the co-riparians, providing alternative methods of calculating these using basic principles which are considered to generally reflect customary international water law. It is concluded that whilst certain of the downstream co-riparians are undoubtedly “water-stressed” an acceptable solution to the allocation of water within the region is attainable. However, this will depend on coupling the allocation of the existing resources to the strategic development of additional fresh water resources in the region, which will also encourage the joint management of the resulting system.

Fractured-karst spring-flow protections: a case study in Jinan, China

Jinan Springs are an important historical heritage in China and have been well known for hundreds of years. Over-abstraction of groundwater in the Jinan area has seriously endangered the hydrological system of the springs, which have stopped flowing for significant periods of time in recent years. A three-dimensional finite-element model programmed primarily at the Hefei University of Technology has been developed to simulate groundwater level change in the large fractured-karst aquifer system in the Jinan Springs field. Various spring protection plans have been explored and their effects on the water table analyzed and compared. It was found that the present rate of groundwater withdrawal from the fractured-karst system in this area was inappropriate for spring protection. The simulated results suggest that decreasing the rate of groundwater pumping from 6.9×105 to 2.7×105 m3/day is needed to protect spring flows. Additional water resource requirements in that area may be met by use of surface water and recycled waste water.

The Sustainable Utilization of Water Resources for a Bioproductive Environment and the Role of Agro-Environmental Education in Korea

The sustainable utilization of the water resources has become an important national agendum in Korea. The great temporal and spatial variations of precipitation and stream flow cause frequent water shortage and floods. The water quality of rivers and lakes has been degraded significantly despite of the continuing investment for water quality improvement. Rapidly increasing water use has placed serious problems to reliable water supply, since the one-third of stream flow is now diverted for agricultural, domestic, and industrial uses. A national survey reported that 1.8 million m of water will be short to meet the demands by 2011. Additional water resources have to be developed and the water demand controls and efficient water use need to be more extensively exercised. The basin-wide integrated flood controls are also important to the sustainable development. The concept of sustainability has been incorporated to the on-going efforts to the water related issues and policies.

Shallow groundwater in a middle mountain catchment of Nepal: quantity and quality issues

The use of shallow groundwater in middle mountain catchments of Nepal is a recent development. It was only in early 1998 that a number of dug wells had been constructed in the Jhikhu Khola catchment. But their numbers are rapidly increasing. While it seems to be a good way of accessing additional water resources both for domestic (current) and agricultural purposes (future), it is very important that the groundwater resources are not overexploited. Current dug wells are used to abstract groundwater, which is seasonally being recharged by the abundant monsoon rainfall. The water levels responded rapidly to the rainfall and differed according to the location of the well. The water quality parameters indicated that the water of most of the wells was not suitable for drinking purposes without prior treatment. Microbiological contamination is of particular concern, in addition to the high nitrate and phosphate levels. Some wells show elevated turbidity levels, indicating that there is an interaction between the muddy surface water and the water in the well.

지표수-지하수를 연계한 수자원이 효율적 이용 - (1) 방법론

가뭄이나 장래 물 부족을 해결하기 위한 방안으로 지표수-지하수 연계이용 방안이 대두되고 있다. 하나의 수원에 지나치게 높게 의존하고 있는 지역은 물 부족사태가 발생할 개연성이 높기 때문에 연계이용을 검토할 수 있으며, 추가 및 신규 수자원 확보 차원에서도 연계이용은 매우 현실적이고 효율적인 대안이 될 수 있다. 본 연구에서는 가뭄과 같은 비상시 안정적인 물 공급을 위해 지표수와 지하수를 효율적으로 연계하여 추가적인 수자원을 확보하는데 적용할 수 있는 방법론을 개발ㆍ제시하였다. 개발된 방법론은 지표수-지하수 연계이용 적지선정을 위한 분석, 가뭄해석을 기초로 한 물 공급 시나리오 도출, 유형별 추가 수자원 확보량 산정 등의 절차로 구성되며, 체계적이고 정량적인 방법에 의해 지표수-지하수 연계이용을 계획할 수 있어 공공기관 등에서 물 관리 방안 수립시 유용한 도구가 될 수 있다. Conjunctive use of surface and ground water is emerging as an alternative to resolve water shortage problems caused by drought or overpopulation. The region whose water supply depends on a single source has high risk of emergency situations, and may need to consider conjunctive use to overcome its weakness. Conjunctive use also can be a realistic and effective solution when additional or new water resources are to be developed. This paper presents a new methodology for managing surface and ground water resources with the aim of supplying water in a sustainable way. The developed method encompasses procedures to assess site suitability for conjunctive use, to devise water supply scenarios based on drought analysis, and to quantify the amount of water attained. It is believed that the systematic and objective features of the developed method enable it to be a useful supportive tool for water management planning and decision-making.

Paddy and Water Environment : Facilitation information exchange and identifying future R & D needs

Agriculture will have to meet the future challenges posed by food security by increasing production while conserving natural resources. The conservation of natural resources is important because of the dependence of agriculture on these resources. This means that the natural environment should be managed in such a way as to assure food security for the present and future generations. So, food security is a matter not only of quantity but also of continuity. In this context, the responsible use of natural resources plays a role of paramount importance. Among the basic natural resources upon which life depends are soil and water. The responsible use of soil and water can be described in terms of sustainability or sustainable development. Sustainable development can be viewed as a transformation process in which the exploitation of resources, the direction of investments, the direction of technological innovation and adaptation, along with institutional changes, are all in harmony and enhance both the current and future potential, to satisfy the needs and aspirations of a growing world population. This process implies long-term perspective for planning and integrated policies for implementation. Increasing agricultural productivity in an environmentally sustainable manner will be crucial in responding to these challenges. In the past, the increased demand for food has been satisfied by the expansion of agricultural land. Today, the availability of new land for cultivation and additional water resources are limited. Moreover, the more or less uncontrolled increase of agricultural production over the last few decades, in both industrialized and developing countries, has pushed agricultural production to, and in many cases over, the edge of sustainability. This means that the traditional methods for increasing production are facing a new challenge; reconciling agricultural development and the conservation of natural resources. Agricultural engineering has been applying scientific principles for optimizing the use and management of natural resources for centuries, and with the new millennium it is playing an increasingly important role. There are at least two reasons for this. First, the wise use of land and water resources will play a role of paramount importance in the provision of food for future generations. Second, the demand for different land and water uses is increasing tremendously, especially in the developed world. Rational water management and land-use planning will help to reconcile these different demands and assure food security, while conserving the environment. In this context, the prospects of increasing the gross cultivated area, in both developed and developing countries, are limited by the dwindling number of economically attracDaniele De Wrachien

Global Water Shortages and the Challenge Facing Mexico

Numerous countries are facing a severe water shortage for food production, drinking water and industry, with profound impacts on the world's poor and the potential for global conflicts. This article traces the past 30 years' trends in irrigation and water productivity and projects global water supply and demand for the next 30 years, including estimates for Mexico. Options to address water shortages are discussed, including developing additional water resources, improving the management and productivity of already developed water resources and increasing food imports. In the short run, problems associated with water scarcity in many regions will become more severe. But with appropriate policies and institutions, the word's water resources can be managed to meet the needs of a much larger population.

Nutritional water productivity and diets

The increase in water productivity is likely to play a vital role in coping with the additional requirement for food production and the growth of the uses of water other than in agriculture in the coming century consistent with the shift from productivity per unit land to productivity per unit water, the nutritional productivity of water is calculated as energy, protein, calcium, fat, Vitamin A, iron output per unit water input. Nutritional productivity is estimated in the agricultural context of California for the main crops and food products. In general vegetal products are much more productive than animal products. Four crops emerge as highly productive for one or several key nutrients: potato, groundnut, onion and carrot. A balanced diet based on these four crops requires a consumption of water (evapotranspired) of 1000 l per capita per day, while the current needs for the diet in the USA is 5400 l, and 4000 l for developed countries. On the basis of nutritional productivity analysis it is further demonstrated that a significant part of the additional water resource to produce food for the next century population can be generated by changes in food habits. A reduction of 25% of all animal products in the developed countries’ diet generates approximately 22% of the additional water requirements expected by the year 2025.

Water reclamation and unrestricted nonpotable reuse: a new tool in urban water management.

Growing urbanization accompanying growing population is increasing the demand for water supply in communities throughout the world. Water resources for many cities are already proving inadequate. Additional water resources are inherently more costly and are often not available because other communities and/or land owners have the water rights. Although conservation, particularly through demand management, may delay the need for additional sources for a short period, the need is inevitable. One approach that has been found to provide substantial additional water for communities is the reclamation of wastewaters produced by the communities themselves for unrestricted nonpotable purposes, such as for landscape and market crop irrigation, industry, cooling towers, air conditioning, toilet flushing, construction, vehicle washing, and environmental enhancement. This is done by providing dual distribution systems. Nonpotable reuse is already widely practiced despite the fact that the reclaimed water distribution systems needed to be installed in existing communities. Inasmuch as additional water is needed for growing populations, the costs would be substantially reduced if the two systems were to be built at the same time in the newly developing areas. Reuse of reclaimed water for potable purposes may be feasible, but it imposes added public health risks that need to be accepted only as a last resort.

Advanced technologies for municipal wastewater purification: technical and economic assessment

The water resources of Kuwait are limited to desalinated water to meet the requirements for all freshwater needs, unreplenishable brackish water as a supplementary source for blending and agriculture, and municipal wastewater which is treated and mainly discarded to the sea. Limited quantities of the treated effluents are utilized for agriculture and greenery purposes. The large quantities of treated effluents have a great potential to replace the brackish water supplies and to redress the balance of demand for irrigation water. Research work was carried out at the Kuwait Institute for Scientific Research (KISR) to assess the technical viability and economic feasibility of implementing reverse osmosis (RO) technology to renovate Kuwait's treated wastewater effluent. This paper describes the adopted treatment, alternative pretreatment, characteristics of the permeate and cost of the renovation treatment. The results indicate that municipal wastewater can be treated by advanced technologies to produce an excellent water which is almost devoid of salts, pollutants and microorganisms. The total cost of such treatment is estimated to be almost half of the distillate cost produced by multistage flash (MSF) plants, whereas the cost of treating the tertiary treated wastewater alone by additional advanced treatment constitutes only 25% of the MSF distillate costs. The Government of the State of Kuwait has decided to implement this technology in constructing a wastewater treatment and reclamation plant at Sulaibiya in the context of privitization to produce an effluent of a quality that can be considered an additional water resource for non-potable uses.

Recent trends and developments: reuse of wastewater in agriculture

Many countries all over the world are facing water shortages. As population increases, water is being perceived as a very valuable resource. Every effort is exerted to use water more efficiently and to make use of every drop of water to ensure the well being of future generations. New trends are developed and practiced in the area of water resources use and water saving. These trends vary from one country to another according to the degree of water scarcity, economic situations, and other factors. Developing non‐conventional water resources is an example of the recent trends in developing new water resources and water savings. Unlike rainfall, rivers, and groundwater which are considered conventional freshwater resources, the non‐conventional water resources include sea water desalination, agriculture wastewater reuse, and municipal wastewater reuse. This paper deals with the reuse of agriculture, municipal, and industrial wastewater as a new trend in developing additional water resources. Special interest is given to municipal wastewater, its characteristics and necessary treatment. Environmental and human health considerations for wastewater reuse, especially in agriculture, are also discussed. Possible consequences of wastewater reuse are introduced. Examples of wastewater reuse practices in some countries are also mentioned.