Multipurpose Water Use Research Articles

Mapping Ecosystem Services in an Andean Water Supply Basin

Socio-ecological dynamics affect the ecosystem services supply and are relevant to generate effective water management strategies; this condition is considered to evaluate under a holistic approach, the water ecosystem services (WES) in an Andean supply basin (ASB) in Colombia. This analysis focus on the connection of biophysical and sociocultural components for the multi-purpose use of water based on The Soil and Water Assessment Tool (SWAT) modelling for Las Piedras River Basin (LPRB). The generated Hydrological Response Units (HRUs), allows to estimate the capacity of the basin for supplying water (quantity) in adequate conditions (quality) for local populations in rural and urban areas, as well as WES zoning. The model was calibrated and validated to generate a baseline scenario, which was complemented with social cartography and participative workshops. The results indicate a low concentration of nitrogen and phosphorus, boosted by specific agro-ecological strategies developed by local communities; however, there are health risks for populations downstream and those that are supplied with water directly from the source. Additionally, Land Use and Land Cover (LULC) affects water availability, which demands restoration and conservation strategies to maintain WES supply for socioeconomic and cultural purposes, since different views on the available WES converge in the basin.

Identification of effective hydropeaking mitigation measures: are hydraulic habitat models sufficient in a global approach?

Downstream of hydroelectric plants, hydropeaking can cause frequent flow variations, resulting in habitat modifications (e.g. hydraulics, reach morphology, temperature, water quality), which can impact organisms (stranding, dewatering, forced drift, growth disturbances) and ultimately may have negative and lasting impacts on biological communities, reducing resilience. Nevertheless, the severity of habitat disturbances vary depending on other existing pressures and local site conditions, which need to be taken into account to achieve effective hydropeaking mitigation. Preserving hydropower flexibility is also a priority to ensure the stability of electric systems without recourse to more polluting alternatives. Given these apparently opposing objectives, we propose a consensual technico-economic framework to guarantee the feasibility and effectiveness of site-specific hydropeaking mitigation, based on our experience as a hydropower operator and a literature review. While existing tools (such as habitat models) can be used to predict expected local effects of proposed mitigation and compare scenarios, predicting biological community responses is not currently possible (lack of in-situ evaluations of mitigation efficacy). These uncertainties and complex socio-ecosystems necessitate a forward-looking global approach that accounts for climate change, multi-purpose water use and electric system requirements, combined with site-specific analyses of the relative importance of hydropeaking impacts with respect to other pressures.

Hydropower potential in the Kabul River under climate change scenarios in the XXI century

Global policies for mitigation of global warming GW will require countries to rely as possible upon renewable, clean energy sources. This includes developing countries, in need to foster suitable life conditions under population growth. Hydropower can deliver such renewable energy, pending water availability and proper management. In central Asia, water resources management is an urgent challenge, especially given desert climate, and the expected impacts of transient climate change hereon. While some catchments will still receive large shares of water from transient melting of the water towers in the Himalayas, others will not, given their little ice cover, in spite of the high altitudes. This is the case of Kabul River of Afghanistan, displaying low rainfall and high altitude, and yet displaying very small ice cover, and where further the present hydropower network is limited and partly damaged by recent conflicts. The goal of this work is to evaluate hydropower potential of the Kabul River and subsequently potential hydropower coverage of energy demand, under the hypotheses that (i) the present network would work at its largest potential and (ii) that hydrological regimes will change in response to scenarios of climate change, until the end of XXI century. To do so, we use a sparse array of data to tune the Poli-Hydro model, able to model hydrology of high altitude, poorly monitored catchments as here. Using modelled (and otherwise unknown) streamflows entering the present power plants (reservoirs + power-houses), we then simulate water management for hydropower purposes. We use two conditions, namely (i) run-of-river ROR and (ii) storage, and (optimal) regulation STO, allowing multipurpose use of water when necessary (e.g. irrigation needs). We then feed Poli-Hydro with IPCC climate scenarios (plus downscaling) until 2100, to carry out a sensitivity analysis (what if? scenarios) of (i) hydrological cycle and (ii) hydropower production. The future hydrological regimes are largely affected by uncertain future precipitation, and so is hydropower production. In spite of potentially increased hydropower on average (+ 1.4% at mid-century, + 1.7% at 2100), driven by variably changing stream flows, some scenarios indicate decreased overall production (down to − 3%) at half century. We provided here a tool usable to (i) assess present and future hydropower potential in the Kabul River, (ii) direct improvement of the present plants network and (iii) benchmark proposals for future network extension.

Methodological Bases of Creation and Development of a New Type of Natural and Technical Systems of Multipurpose Water Use in Urban Areas

In the development of the class of natural-technical systems (NTS) “Natural Environment-Object of Activity-Population” (“NE-OA-P”) on the use of water resources in the multifaceted types of economic and other activities, giving the results of theoretical studies of a specialized type “NTS” in where the component “PS” means the natural water environment (NWE) of a water body as a source of the multi-purpose water supply system (MWS) of the objects of urban households, settlements, enterprises of the fuel and energy complex (TPP, HES, NPP); Under the “OA” water intake technological complex (WITC) is considered, which includes various for the functional purpose of hydraulic structures (HS) and devices for ensuring the selection of estimated water flow (Qm3/s) with an environmentally safe level of protection of the water environment of the water body in the zones of influence of the WITC and the functional work of the treatment facilities in the composition of the MWS; under the component "P is considered MWS that provides water of normative quality to specific water consumers and water users. The methodological basis in creation of new type NTS “NWE - WITC -MWS” considers the system analysis and the approach which is based on concept of “System”. The methodology for creating and developing this type is based on 4 axiomatic conditions: (1) existence as a fundamental characteristic; (2) a multitude of structural formations; (3) unity, as the relationship between natural technogenic components; (4) sufficiency of the initial material for an assessment of an ecological condition of water environment «NWE - WITC -MWS".

Selective withdrawal optimization in a multipurpose water use reservoir

Dam construction in arid and semiarid regions is generally related to the risk of increased salinity, due to water passage in contact with salty formations. Hence, it is important to take reservoir thermal and salinity stratification into account in operational rules. In the present study, a simulation–optimization model was developed to determine the amount of water release from various outlets to discharge the brine from hypolimnion layer considering the downstream water quality limitations. The most appropriate time, rate, and concentration to release brine were determined based on water consumption conditions and downstream water demand and river ecology characteristics. The proposed methodology was used to improve the water quality condition of Gotvand Dam constructed over Karun River in southwest Iran. The dissolution of the Gachsaran formation located in Gotvand Dam reservoir has gradually increased the salinity of hypolimnion layer water three times more than that of the seawater salinity. The results indicated that late winter is the most appropriate time to release brine water. If the brine water is not released, the very salty water gradually encompasses the epilimnion layer when the reservoir dead storage is filled with sediment. Results show that the TDS concentration of epilimnion layer gradually increases until 8000 mg/l by increasing the volume of reservoir sediments, which may be regarded as the source of economic, social, and environmental crisis.

Assessment of Pollution and Improvement Measure of Water Quality Parameters using Scenarios Modeling for Sungai Selangor Basin

Sungai Selangor is very important from the viewpoint of water supply and multipurpose water use in Malaysia. The water quality of this river is degrading due to point and non-point sources of pollution. This study, focus on the water quality assessment and simulation the effect of the pollution sources from urbanization to the Sungai Selangor basin. Water quality Index (WQI) is used to define the status of river water quality and the QUAL2K was used as a simulation model. Water quality parameters DO, BOD and NH3-N have been chosen for modeling. In addition, five different model scenarios were simulated to observe the impacts of pollution sources on the Sungai Selangor water quality. WQI results showed that most of the stations in this river basin recorded water inferior to Class III. The water quality model presented different scenarios for changes of Sungai Selangor water quality. Simulation results for different scenarios showed that reduced levels of BOD and NH3-N at 51.10% and 66.18%, respectively, can be obtained if Scenario-5 is employed. The river water quality issue in the Rawang sub- basin within the study area is considered crucial to create significant improvement within the sub basin and in the downstream area of Sungai Selangor basin.

Bathymetric and Volumetric Analysis of Jebba (Hydropower) Dam Harnessing its Capability for Multipurpose Use

The need to carry out routine bathymetric survey on dam in order to analyse the quantity of water in the dam’s reservoir cannot be underrated. “multipurpose water uses of hydropower reservoirs” has been the world water council advocacy. Multipurpose water use include categories, such as domestic purposes, cooling of power plants, irrigation, mining, recreation, navigation, fisheries, etc., This research uses topographic and bathymetric data obtained from field operations to compute the volume of water present in the dam. Midas Surveyor dual frequency GPS echo sounder, Trimble 5700 Dual Frequency GPS ‘Base Station’ receiver and Trimble 5800 Dual Frequency GPS ‘Rover’ receiver, were employed for data collections. Data processing and presentation were done with Surfer 10 software. The volume computed from data analysis gives 3880 x 106 MCM. The volume of water needed to run the six turbines per day added up to 1,735200 litres and that of per capita use was 0.006 litre per day for minimum and 0.025 litres per day for maximum. The volume left after removing other withdrawer was 62% of the actual volume computed for the dam.

Enhancing resilience to water flow uncertainty by integrating environmental flows into water management in the Amudarya River, Central Asia

The wetlands of the Amudarya River delta in Uzbekistan provide valuable ecosystem services to the local human population which has suffered severely from the loss of the Aral Sea, desertification and the post-soviet socio-economic transition. The region is also particularly vulnerable to the impacts of climate change as a recent severe drought has shown. In this contribution, we assess the potential and implications of incorporating environmental flows into management of the Amudarya River for improving the provision of wetland ecosystem services and enhancing resilience of the social-ecological system to river runoff uncertainty. Our assessment is based on analyses of 1) the current vulnerability of deltaic wetlands to years of low water availability, 2) expected regional climate change and its impact on water flows to the wetlands, and 3) alternative water use options to enhance environmental flows under a changing climate. The results provide a ranking of these options with respect to their benefits for the provision of environmental flows and implications for agriculture. Their realization, however, poses challenges that cannot be tackled by technical interventions of redistribution and efficiency increase alone but call for institutional changes and moves towards multi-purpose water use. The diversification of impacts and livelihood options would allow enhancing the resilience of the social-ecological system to climate or socio-politically induced changes in water flow.

Assessment of losses in multipurpose water use

Losses in different components of water resources systems multipurpose water use are considered. A method is proposed for their assessment in a general form and with the use of Makrov processes.

Zonal management of multi-purpose use of water from arsenic-affected aquifers by using a multi-variable indicator kriging approach

This work presented a probability map of groundwater resources for multi-purpose uses (irrigation, aquaculture and drinking water) of arsenic (As)-affected aquifers in the Lanyang Plain, northeastern Taiwan. The assessment was based on As and other several compounds and factors that adversely affect water-quality. Multiple-variable indicator kriging (MVIK) was adopted to evaluate numerous hydrochemical parameters for the three water-quality standards in Taiwan. Hydrochemical parameters of groundwater were classified into four main hazard categories – saline hazard, nitrogen hazard, As hazard and Fe–Mn hazard. Safe and potentially hazardous groundwater regions for multi-purpose use were delineated according to estimated probabilities by using MVIK. Analytical results for MVIK critical probability of >0.5 demonstrate that the proximal-fan, partial central distal-fan and mid-fan, and northern distal-fan aquifers complying with most water-quality standards are optimal zones for extracting safe groundwater. Notably, the deep aquifer has a high hazard rating and is less safe than the shallow aquifer. The Fe–Mn hazard in Lanyang Plain groundwater presents in most aquifers, and is partially combined with other hazards, such as the nitrogen hazard and the As hazard. A zonal management plan based on safe groundwater use is formulated to help local governments develop groundwater resources in the Lanyang Plain.

Influence of Water Quality on Multi-Purpose Water Use

Influence of Water Quality on Multi-Purpose Water Use

Relationship between Water Quality and Multi-Purpose Water Use

Relationship between Water Quality and Multi-Purpose Water Use

Benutting van landbouneweprodukte en gesuiwerde rioolwater in akwakultuur in ontwikkelende gebiede van Suid-Afrika

The serious shortage of potable water supplies for domestic, agricultural and industrial requirements necessitates an investigation into the optimal utilization of this scarce commodity in South Africa. The multipurpose use of water in agriculture through its effective utilization in integrated aquaculture-agriculture food production systems is one way of optimising the application of such water. In the present series of investigations, agricultural wastes such as chicken, cattle and duck manure were applied as organic nutrient in freshwaterfish ponds with and without supplementary feeds. Fish used in polyculture production for the optimal utilization of the various trophic levels in manured fishpond ecosystems included the European and Chinese carp species and the sharptooth catfish. Supplementary food consisted of 18-45% protein fish pellets. As an alternative to organic manures, treated sewage effluent with fish pellets was used to evaluate its fish-production potential. Fish species used in monoculture and polyculture production included the European common carp and the sharptooth catfish. The role of water temperature on the fish-production potential of these systems was also investigated. The possible value of integrated aquaculture-agriculture systems in protein production in rural community development in South Africa is discussed.

Planning and Management of Water‐Resource Systems in Developing Countries

The multipurpose use of water in all types of human activities and the intensive development and urbanization of settlements have resulted in a considerable increase in water demand and water pollution. This is why it is necessary to build complex, spatially scattered, multipurpose water-resources systems. The multiple objectives and limitations encountered in the planning and management of such systems result in the multidimensional mathematical formulation of the problem and in the application of complex models that need to be simplified. Their simplification often makes the obtained results and the influence of different criteria and limitations on the choice of a final solution somewhat unclear. To eliminate these weak points in the planning of complex water-resources systems, a multiphase optimization procedure is developed, leading to the development of complex, multipurpose water-resources systems.

Influence of different downstream users on single multipurpose reservoir operation by chance constraints

A chance-constrained model is applied to solve the problem of long-term planning of the operation of a single multipurpose reservoir. Apart from the direct multipurpose use of water from the reservoir downstream, releases are available for use. The influence of downstream users is taken into account by a special form of objective function. Releases are bounded by the capacity of the outlet works above and by the guaranteed minimum from below. These two bounds are constraints on the control space. The model uses a chance-constrained programming algorithm to yield the control trajectory (releases) closest to the optimum. The properties of the chance-constrained program reveal a strong influence of changes of the control space on releases. This enables a release strategy to be derived which will increase the utilization of water from the reservoir. The application and results presented in this paper refer to the Prohor Reservoir on the Pcinja River in the Vardar River basin, Yugoslavia. Key words: multipurpose reservoir, mathematical modeling, optimization, chance constraints, control space.