Search

The applied procedure and the achieved results in building a digital elevation model (DEM) corresponding to Marzal neighborhood, Luanda, Angola, according to the requirements of hydrological modeling for the study of hydrological processes in an urban environment are presented and discussed in this paper. The data used came from different sources and scales. Data from the Director Plan, detailed surveying, topographic maps with a scale of 1:25000, and satellite images were employed. The adequate DEM for hydrological simulation was created using spatial modeling tools from Geomatics domain. [ABSTRACT FROM AUTHOR]

The designers of road (highway) cross-drainage structures frequently use culverts instead of bridges. However, culvert design is usually characterized by some conceptual errors which persist without modification because of lack of critical analysis and knowledge of useful experiences. In this paper, the proposed solution attempts to offer a novel type of hydraulic low cost structures for conveying the surface water through and over the embankment as well as fulfilling the following: first, for the design discharge the culvert suffers no damage to the embankment nor to the pavement and, second, in case the discharge increases the water is allowed to flow over the pavement (embankment) without damage; naturally the traffic would suffer a short interruption. [ABSTRACT FROM AUTHOR]

A water management plan helps to organize, manage, use, protect, restore and conserve the resource, aimed at sustainable development, in order to find a balance of its use among agents involved in a specific hydrographic unit. This paper presents a proposed water management plan, based on the analysis and characterization of the current situation of hydro-socioeconomic- environmental systems, found in the lower area of sub-basin Armería river in Colima, México, by means of a base line and the identification of the origin of externalities. This is intended to be the basis for the creation of a committee to help coordinate, implement and evaluate the actions considered in this proposal. [ABSTRACT FROM AUTHOR]

In order to reduce flooding vulnerability in Rosario city and surroundings (Santa Fe, Argentina) the Provincial Water Authority managed the installation of a telemetric network to monitoring hydrological variables, along with the development of a river levels forecasting model. This paper presents the structure of the mathematical model used and some partial results. The model's architecture is based on four modules: rainfall generation, estimation of antecedent soil moisture conditions, initial loss and infiltration calculation, and runoff simulation and levels forecast. The performance of the proposed model was successful in terms of comparison between measured and forecasted levels. Medium-size events evidence the sensitivity of the results to the antecedent soil moisture conditions; while the results for important rain events have greater certainty. [ABSTRACT FROM AUTHOR]

The paper shows the experience in handling the design of Caibarien- Santa Maria key causeway to fit it with the environmental characteristics of the watershed in which it is located. By means of a cause-effect modeling graphic, corroborated by an up-dated informatics software, it is demonstrated the fundamental character that keeping the ocean-island shelf interchange has, as well as the hydrodynamics, in the preservation of the marine environmental characteristics. It is also explained the general strategy that was followed, on the assumption that the causeway is, according to the environmental point of view, a hydraulic construction as a set of its main components: the road layout, the calculation of bridges by hydraulically quasi-homogenous sections, the manner the bridges are located, the off-road induced works and the so-called ecological bridges. [ABSTRACT FROM AUTHOR]

As a result of INRH policy, related to evaluation, design and construction of infrastructure for water resources exploitation, a diversified development plan was elaborated. As a complement of the plan the joint use of waters is considered, consisting in the use of ground water for supplying population located in this area, distributed through water networks, and the capacity created on reservoirs being used for irrigation purposes. Nevertheless, during severe droughts, ground water is also used for irrigation among other uses. All these actions have contributed to diminish overexploitation of the South Aquifer, which provoked marine intrusion with damages to important sectors of it. Besides, they stopped the soil salinization process and provide good quality water for any purpose. This paper describes experiences of the authors on the subject. [ABSTRACT FROM AUTHOR]

Results of the present paper are concerned with evaluating pollutant contributions to aquatic ecosystems according to the products processed in Cuban fishing facilities. The captures in 1955-1999 were between 3 950 and 23 970 t/year in 12 years of sampling, with BOD between 56 and 342 t/year and of DQO between 111 and 676 t/year. The principal nutrient was total nitrogen, followed by total phosphorous and finally ammonia-nitrogen, representing a total contribution of 136,3; 52,7 and 18,0 t/year respectively in those 12 years. The report culminates with the possible affectations caused by polluted water discharges to the ecosystem, recommending the use of the information offered in this document with the objective to elaborate future plans allowing the establishment of environmental management programs. [ABSTRACT FROM AUTHOR]

This paper describes an experience in the use of mathematical models and load tests on hydrotechnical structures. The results obtained from the load test performed on the sheet pile of a dock, located in the eastern part of Cuba, are presented. Horizontal and vertical deformations were measured. A comparison is made between the theoretical methods for deformation calculation and the mathematical methods based on the finite-element method. Finally, the coincidence of results obtained from the numerical model and those of a real-scale load test is proved, thus showing that deformations could not become a risk if the dock is subject to a new load system. [ABSTRACT FROM AUTHOR]

Wrong selection of full-load power of induction motors which are being purchased at present to drive water pumps and also an incorrect selection of their nominal performance voltage can lead to unexpected practical problems during pumping in far rural pumping stations. A thorough study is presented in this paper leading to a set of proposed measures in order to eliminate those problems which can frequently arise in motors connected in places which are distant from transmission substations of the national electropower system. [ABSTRACT FROM AUTHOR]

The use of GIS (Geographic Information Systems) has been widely used for urban waters management. One step in the development of this field has been to use GIS information not just for mapping and consulting, but also to analyze trends and make decisions by means of the applications provided by spatial analysis. Spatial analysis in GIS comprises a group of procedures used to carry out the study of the territorial structures and relations based on the knowledge about the position and features of the geographic entities resulting from the variables involved. This paper proposes its implementation for the processes of planning and decision making within a water supply company, which is illustrated by practical cases with real data. [ABSTRACT FROM AUTHOR]

Companies devoted to water supply and sewerage service activities usually have a series of drawbacks such as the poor system knowledge due to lack of data about networks and low trustability of the existing information, as well as the poor usage of tools to improve management. It is compulsory to stop deterioration of these systems so as to make them more efficient. The most effective means to achieve that goal is by using tools like geographic information systems (GIS). In this paper, the authors carry out an analysis of the use of GIS in water management companies. They explain GIS design as applied in Aguas de la Habana enterprise, as well as its links with other technologies that can be applied to any other water supply and sewerage company. [ABSTRACT FROM AUTHOR]

The Instituto de Hidrología, Meteorología y Estudios Ambientales (IDEAM) in Colombia, has conducted a series of studies on water resources, which articulated with the laws and regulations in force (Law 99 of 1993) gives a framework to face situations of conflict over use and environmental criticality related to this resource. Many Colombian rivers are contaminated by improper handling, as is the case of Cuja subbasin (near the town of Fusagasugá) that is part of the basin of the river Sumapaz, close to the moor of the same name. Additionally, there is a struggle for water in this moor. In this paper, from a holistic perspective, different possibilities or strategies are proposed to achieve a rational use of water resources, initially in a pilot area of the Cuja river. [ABSTRACT FROM AUTHOR]

High density polyethylene (HDPE) in flow pipes is displacing other traditional materials in water supply systems. Calculation of gravity water pressure pipe flow is focused in finding a hydraulically functional pipe diameter with enough thickness to withstanding hydraulic pressures to ensure an economical solution. The selection of the pipe diameter is then a complex process from the hydraulic as well as the structural points of view. The scope of this paper is to identify, from a standard pipe catalog, economically feasible combinations of HDPE pipe diameters for gravity water pressure flow and to guide the selection to the best solutions. [ABSTRACT FROM AUTHOR]

Flood hazard criteria in urban areas, considering combined action of depth and velocity, have been developed for rural basins and are applied in fluvial flooding cases. By using GIS tools and the modules for spatial analysis an analysis of flood risk in urban watershed based on multicriteria decision analysis and combinatorial weighting factors has been developed. The aim of this paper is to make contributions to the mixed weighing method to determine urban flood hazard. Risk maps were developed in a case study by applying EPA_SWMM model to simulate a 1 hour and 28.8 mm depth rainfall event. Finally, new criteria are proposed for standardization of this indicator by changing the normalized scale, from a qualitative sensitivity analysis and comparing hazard maps. [ABSTRACT FROM AUTHOR]

In the last few years Cuban analysts have been working to obtain flood hydrograms in some regions of the country applying HEC-HMS model but the experience is not yet enough. The present paper reports research work with HEC-HMS model in mountainous basins of the Cuban eastern region and some recommendations are obtained from its application in Las Coloradas basin. Valuable experiences were derived with calculation methods and their best application range as well as suitable parameter values for them. Physico-geographic and climatical characteristics of eastern mountainous basins were taken into account and their existing hydrometeorological information. [ABSTRACT FROM AUTHOR]

The economic advantages of a looped network have not been considered in any of the optimization models found in the literature. This paper introduces a new formulation and methodology in an attempt to give a practical solution to this problem. The new formulation consists of a non-linear optimization model solved by classical differential calculus and the Newton-Raphson technique. An example shows how the looped network can be less costly than a branched one. Previous research usually optimizes the network for a given design demand. Also the value that should be specified as the desired network reliability has not been reported so far. This work introduces a methodology to obtain not only an adequate value for the reliability of a looped network but also the appropriate design demand as well based on a thorough cost analysis. A second example illustrates the detailed performance of this methodology. [ABSTRACT FROM AUTHOR]

Teaching in Hydraulics is based on theoretical equations and empirical solutions given by researchers. Also results from physical and mathematical models are used. But not always flow behavior can be clearly visualized or, as with physical models, specialized laboratories are required. Therefore, a tool is needed to reproduce, in quality and quantity, the movement of fluids across different types of conduits. This paper deals, for the first time in Cuba, with the application of visual models to visualize flow behavior under different situations. By applying the visual modeling software Flow-3D, solutions to flow problems in channels and pipes can be visually observed, thus enhancing the teacher's action. Also student comprehension is highly improved as he can watch different alternatives of flow under various working conditions. [ABSTRACT FROM AUTHOR]

The water distribution system called "Falconiano" supplies water to the main cities and the most important oil company refinery in the North-Central region in Falcón state, Venezuela. Since the last decade many industrial and touristic projects have been developed in this area. As population increases new fresh water demand arises, so an operational optimization will be necessary. This is the main purpose of this preliminary paper. A data base with physical and performance characteristics of the storage tanks and reservoirs subsystems was built. Furthermore, level, inflow and outflow series for each tank were evaluated applying tools of statistics. Some inconsistencies in the record series were found. The demand pattern was obtained for one year (2008). [ABSTRACT FROM AUTHOR]

The new Hydraulic Engineering Curriculum started in the academic year 2007 - 2008. As innovative aspects can be mentioned: the Hydrographic Basin - the knowledge invariant for the whole career -, the Integrated Principal Discipline and the Career Professional Project. Other important characteristics of the Curriculum are: a wider basic formation, the conception of the Curriculum as composed by three parts: basic (compulsory), proper and optional- elective, a wide and generalized use of informatics and ICT, etc. This paper focuses on the Integrated Principal Discipline, its main role in the process of professional formation through: the subject Introduction to Hydraulic and Environmental Engineering, six Integrator Projects, Labor Practices and the Diploma Thesis as the final exercise of the whole career. [ABSTRACT FROM AUTHOR]

This paper presents a study about regional analysis of maximum rainfall series. A summary of several aspects usually covered in regional analysis is introduced, such as parameter estimation, frequency analysis and others. The results of an example using the so-called "index flood" method proposed by Dalrymple in 1960 are shown. The case study refers to the annual maximum rainfall series in the river Zaza basin. As a conclusion of the study in this basin, it can be established that when it is divided into three sub-regions, they can be considered as homogeneous and they can be adjusted to different theoretical probability distributions. [ABSTRACT FROM AUTHOR]

"Lázaro Cárdenas" and "Francisco Zarco" water reservoirs are located in central- northern Mexico. In order to improve water balance, transit time and Doppler effect ultrasonic level gauges were placed in both reservoir outlets and in the river interconnecting them. In the first dam outlet two ultrasonic transit time sensors were placed in each of its three tunnels. In the "Nazas" river, communicating dams, two ultrasonic level gauges were settled, both with redundant gauges of level and discharge. In "Francisco Zarco" dam outlet a Doppler current meter was set as well as, in the river bottom, a redundant gauge of level and discharge. This paper describes the selection of each type of gauge, the basics of its technology and how they should be placed and operated. A favourable impact has been achieved in the improvement of water management in the zone. [ABSTRACT FROM AUTHOR]

Hydrologic studies in Coro river basin have neither considered wasted water by spillway overflow nor the "El Isiro" dam break which supplies Coro city. An accelerated urbanization existing downstream of the reservoir in the river floodplain considerably increases posible damages. This paper updated the hydrologic study where "El Isiro" subbasin was included as well as the posibility of the dam break. The impact on the basin response was evaluated allowing the quantification of the flood threat and consequences. The study was supported on HEC-HMS v.3.3 software. Results show that maximum discharges at the end of the basin increase by some 20-35% including spillway discharges. When the dam break is included they are magnified 5-17 times. On the other hand, under the break event peak times are considerably reduced. This work represents a valuable contribution to the flood risk management in the zone. [ABSTRACT FROM AUTHOR]

Water resources systems usually integrate a group of components or subsystems, each with their own set of inputs and outputs. Operating these systems is a continuous process that should be rigorously controlled to insure objectives and goals. The main aspects to be developed for monitoring and studying hydraulic systems operation are: the equipment for acquisition of system variables which characterize its performance and the implementation of software tools to facilitate interpretation of gathered data. In this paper a technology for field variables logging, in deferred time, developed by Hydraulic Resources Group of the Hydraulic Research Center, is presented. Additionally, WinRM application results to Santa Lucía Aqueduct and Sewer Enterprise for water control and management activity support are included. [ABSTRACT FROM AUTHOR]

A great diversity of man-produced contaminating agents goes to the water, directly or indirectly, provoking changes which are contradictory with the harmonic unfolding of nature. A pollutant, not being the most aggressive among organic polluting agents, is the one coming from the industrial processing of fishing resources. Despite in some aquatic resources processing facilities waste waters treatment systems have been installed, the fact is that more than 70% of them lack any treatment. For this reason, in the paper physical and chemical characteristics of the fishing industry organics riles are indicated as design basic data for treatment systems of these waters. [ABSTRACT FROM AUTHOR]

The paper presented shows the results of an experimental study by physical model, in a tank of irregular waves at the Center of Studies in Ports and Coasts (CEPYC) in Spain. An empiric model is obtained to estimate the average rate of overtopping of the storm wave over curved seawalls. The conditions selected for the study reflect the environmental characteristics and marine climate of the Cuban coasts. The results obtained are applied to the well known Malecón de la Habana which suffers severe damages during the occurrence of meteorological phenomena generated in the Gulf of Mexico. The results are shown in tables and graphics. [ABSTRACT FROM AUTHOR]

The paper deals with the operation of a plant designed for purification of 300 L/s with a conventional flow diagram including screening, cloration, coagulation and contact clarification. In practice the operation manual is seldom included with the project which negatively influences on the plant setup and start as well as on general plant behavior. The operation manual hereby presented is intended as a guide to the engineer in charge of the plant so he can develop detailed instructions to operators in such a way that plant operation is accomplished efficiently and attaining its primary objective: production of high quality water for human consumption at the least cost and the safest way. [ABSTRACT FROM AUTHOR]

In supercritical flow canals it is very important to consider the air - entrainment phenomenon. This phenomenon is needed for the hydraulic design of the canal wall height. In this paper a comparison is made between several existing methods for the air - entrainment determination and a new simpler method is proposed which appears to be as trustable as the best of the existing ones. [ABSTRACT FROM AUTHOR]

This paper evaluates different types of groundwater exploitation systems used in coastal areas and in small islands where seawater intrusión can occur. In many cases using open trenches for groundwater supply inconveniences appear because of seawater penetration associated with hurricanes. Pumping wells should not be used even shallow ones because of intrusion cones. It is also recommended to substitute open trenches by horizontal drains with control systems for levels and water quality in the collectors from where water would be pumped as if they were storage deposits. This also decreases evaporation losses, environmental drawbacks and contamination from drag of solids as well as reduces the possibilities of seawater penetration. [ABSTRACT FROM AUTHOR]

This paper deals with developing criteria to find proper use of different types of diffusers, to evaluate irrigation quality and to determine the possible relationship between the working emitter type and irrigation uniformity to the potato crop yield. Results show that the emitter type is neither related to the irrigation quality nor related to crop yield. On the other hand a tight dependence is clearly observable between the irrigation uniformity and the crop yield. [ABSTRACT FROM AUTHOR]

The paper starts with a brief analysis of the environmental contamination in the country and its impact over land waters. The National Program Against Contamination for the period 2009-2015 is presented as an answer to the problem identified in the National Environmental Strategy 2007-2010 (EAN) and the working platform in which all national efforts are integrated in the struggle against this threat. Program objectives and targets are described as well as intended actions. It is concluded that the program is a strategic tool which, by considering conditions, needs and priorities of the country, is capable of successfully confronting the contamination problem of land waters and the other environmental components. [ABSTRACT FROM AUTHOR]

The hydraulic jump in circular conduits has not been studied in depth. Some reports even consider that theroretical values of its parameters are not in agreement with the few experimental data available. Theoretical treatment of the problem is hereby presented with calculation expressions and graphics for its solution. Validity of the results is shown provided that all involved coefficients are correctly fundamented. To this end reported test results in the literature are re-elaborated. Comparison between proposed approximate formulas to calculate jump length and an empirical dependence existing within hydraulic properties of these conduits, shows the need to apply the latter in order to obtain reliable results. The paper also calculates the hydraulic jump efficiency in consumption of the excess energy in these conduits. [ABSTRACT FROM AUTHOR]

Important investments have been realized in the country toenhance technological level of irrigation practice. Central pivot machines have been given considerable importance in the investments. Nevertheless, studies and information are still insufficient regarding operation costs of these irrigation systems. Analyzing operation costs of central pivot machines under different exploitation conditions is the objective of the present paper. After a thorough analysis of alternatives results show a tendency to reduction of operation costs when the area associated to the irrigation system is increased. Also a reduction is obtained when electrical motors are employed instead of those of internal combustion. [ABSTRACT FROM AUTHOR]

The Tequesquitengo Lake water level in XIX century was about 20 meters below present-day levels and within a time period between 1820 and 1865 the lake level gradually increased and the small town existing on its banks was completely submerged. The study of the lake-aquifer interaction was developed by the author working at the Instituto Mexicano de Tecnología del Agua (IMTA). In this paper an attempt is made to explain what might have happened in the XIX century. After building a scenario representing natural conditions at that time, two alternatives were tested which presumably were the explanation given to this strange event. Pertaining conclusions were obtained. Finally, a third alternative was analyzed in which a possible natural recharge might had come from the deep aquifer as a result of a natural accident. [ABSTRACT FROM AUTHOR]

Flood risk management in urban areas settled over floodplains must be supported on quantitative analysis toestimate probable damage of their impact. This will be the basis for authorized institutions in taking measures to reduce the risk. When estimating flood risk in these zones due to river overtopping threat and vulnerability must be quantified as well as probability of occurrence of the phenomena and its damage. Estimations must result from hydrologichydraulic modeling and physical damage determination caused by hydrometeorological events originating floods in basins. At present there is no agreement as to which is the best methodology to be applied. Neither is this paper aimed at selecting the best. It only presents a review and analysis of accumulated experience from the application of several methodologies to concrete case studies. [ABSTRACT FROM AUTHOR]

The exponential law of flow is revised through dimensional analysis leading to the determination of hydraulic conductivity (HC). But HC depends on the gradient exponent which has limited the use of the exponential law in practice. The paper shows how the velocity can be calculated given the gradient and the properties. A general relationship between hydraulic conductivity and that of Darcy is derived as a function only of the exponent and the gradient. Besides, an excellent correlation is obtained between a gradient quotient (hydraulic over Darcy critical) and the exponent of the gradient in the exponential law, derived from extensive data of experimental results of many authors. Lastly, a correlation between Darcy critical hydraulic gradient and intrinsic permeability is made to estimate Darcy critical gradient when no information is available about the media equivalent roughness. [ABSTRACT FROM AUTHOR]

In this paper a mathematical model is presented for the optimization of aquifer resources management. The model is based on the porous media flow AQÜIMPE model embedded within a linear programming algorithm. Theoretical considerations are introduced first and then it is applied to a case study in which a number of different linear objective functions (LOF) are tested. One of the LOF's is to maximize the discharge flow from the aquifer and the other LOF is to minimize drawdowns in the discharge nodes. The whole model has been built on the mathematical assistant MATLAB and has been made fully interactive with the GIS tool AQTRIGEO which is associated with AQÜIMPE. [ABSTRACT FROM AUTHOR]

Geographic information systems (GIS) are an important tool for storing and managing geographically referenced data. They can represent real world through digital data and data from simulation of natural or antropic processes over a given scenario for a given time. GIS has multiple applications. It is widely used in hydraulics and nowadays many resource management systems are incorporating applications. In the Centro de Investigaciones Hidráulicas (CIH) of CUJAE a platform is developed for water resources management. One of its components is GIS. In this paper general characteristics of GIS are explained, development tools and the specifically designed GIS for the Modular Integrated Platform of water resources. [ABSTRACT FROM AUTHOR]

Maximum storm rainfall is processed to obtain frequencyintensity-duration (FID) curves. The proposed methodology by Cruz Gámiz (1998) is applied here. Original rain gauge recorder cards are processed by means of image treatment techniques with a high resolution scanner or a digital camera of at least four megapixels and an image digitizer software. Then the digitized data is converted into rain information through a Visual Basic software specifically designed for this application. In this way the databases contained in the original paper supports, coming from existing traditional rain gauge recorders is transformed into digital support and post processed to obtain all the information needed to calculate FID curves. [ABSTRACT FROM AUTHOR]

The time of concentration and the so called Curve Number are two important parameters for obtaining runoff hydrographs at any point of a natural river system in a watershed from rainfall data; in Cuba, the time of concentration is usually calculated considering two time components (sheet flow time and channel flow time). In some other cases the time of concentration is calculated using only one component (channel flow time). Some mistakes could arise due to this simplification, because according to updated bibliography three components must be taking into account to compute the time of concentration: travel time in sheet flow segments over the watershed land surface, travel time in shallow flow segments and travel time in channel segments. For the Curve Number determination, a general coincidence exists about its definition and the procedure to calculate its values. Nevertheless, the procedure can become bothersome in the case of a watershed with several soil types and soil uses. Criteria and procedures for both parameters are shown in this paper, which contribute to an adequate solution to estimate their values. [ABSTRACT FROM AUTHOR]

Looped networks have been used extensively in practice with the advantage of reducing the amount of affected users under a failure situation. The concept of reliability is applied as an attempt to measure quantitatively the possibility of keeping an adequate service level for a given time horizon. From the above, one should expect a looped network to be more reliable than a branched network under similar layout and sizing characteristics. In this paper two quantitative indices to measure expected network behavior are discussed: reliability and tolerance. These indices are calculated and a comparison is made between looped and branched networks. [ABSTRACT FROM AUTHOR]

Ski – jump energy dissipators are widely used in practice because of their well – known effectiveness. Nevertheless, some uncertainty exists associated with the dimensions of the scour – hole appearing downstream of the structure. In this paper a new method is presented in which this problem is solved. This method includes the spillway stability checking as part of the design process and also the stability checking of any other construction near the zone of energy dissipation. Finally, a methodology is suggested for the design of these dissipating structures which includes considering discharges below the design discharge. [ABSTRACT FROM AUTHOR]

General science development and Cuba education achievements together with systematic improvement of Academic Curriculum in Cuba universities demand a permanent refinement of performance attitudes of teachers as well as of students. On the other hand the need arises to involve students to community endeavours science the very first years of their career and this, in turn is reflected into necessary changes to their hydraulic engineering academic curriculum with purpose of graduating a high quality engineer. As a consequence of the above, the Irrigation and Drainage engineering has been adapted to this new situation. In this paper consideration is given to the main changes that have been introduced in the discipline in the context of the new academic curriculum. [ABSTRACT FROM AUTHOR]

It is a well known fact that the optimization of a looped network, under classical procedures, gives a branched network as a result. Nevertheless, even when looped networks seem to be economically not justifiable, they are used extensively in engineering practice. This is probably because the economic advantages of a looped network -arising from its behavior when a pipe failure or breakage is present- have not been explicitly considered in the objective function of optimization models found in the literature. This paper introduces a new formulation in an attempt to give a practical solution to this problem. Based on principles established by Cristina Chiong's doctoral dissertation in 1985, this new formulation also consists of a non-linear optimization model which is solved by classical differential calculus and the Newton-Raphson technique. What is new here is the introduction of an additional term in the objective function that has not been previously considered. An example shows how the looped network can be less costly than a branched one. [ABSTRACT FROM AUTHOR]

The environmental occurrence of pharmaceuticals has been recognised as an area of increasing concern. After administration of pharmaceuticals the patients excrete it, and those unused medications sometimes disposed of in drain. The pharmaceuticals enter the aquatic environmental and eventually reach drinking water if they are not biodegraded or eliminated during sewage treatment. This paper gives an overview on the current state of the scientific knowledge in this field. It compiles most recent data and information from some scientific studies and projects carried out in different countries about detection. [ABSTRACT FROM AUTHOR]

The results obtained in the Centro de Investigaciones Hidráulicas, ISPAJE, Cuba in the use of the first version of MultiH_Virtual for Hydraulic teaching, are presented. This product allows the reproduction of practices in the office, the university or in the home and improves the pregraduated and postgraduated formation based on the use of computer and electronic equipments. This paper describes the most relevant aspects that MultiH_Virtual offers to students and profesionals of cuban and foreign universities, being remarked their strengths and the lines of their future development. [ABSTRACT FROM AUTHOR]

Wastewater treatment using conventional technologies is not always a good solution to small population groups; most of the time, conventional technologies for small population groups lead to oversized solutions and it is necessary to look for non-conventional proper solutions: sanitary security and social and economically sound solutions. Regarding appropriate technology, systems are classified in: treatment in situ and system of modified sewer. In this paper, these two kinds of system are applied to obtain a wastewater treatment solution for a population of 500 inhabitants at Consejo Popular Pocitos Palmar. System of activated sludge extended aeration was found to be the most appropriated for the design conditions in this case. [ABSTRACT FROM AUTHOR]

Flooding due to rainstorms over watersheds are considered as natural events causing disturbances, risks and damages to many activities, properties and even to human existence. Problems associated to this extreme event are in reality extremely complex because its occurrence is affected by many factors like physiographic, hydrografy and climatology of the basin. Characteristics and use of the soils, vegetation, size and location of populations, works and men activities also influence on the studied areas. A general methodology to deal with flooding and two case studies solved by using different professional software in Tarija City, Bolivia and from Jaruco dam until the confluence with rivers Blanco and San Miguel along Jaruco river in Havana province are presented in this paper. [ABSTRACT FROM AUTHOR]

This paper represents the culmination of the study about the evolution of Hydraulic Engineering Education in Cuba from their beginnings until the present time. Since the establishment in 1976 of the Ministry of Higher Education (MES) a process of continuous improvement in the curriculum of studies of university careers was accelerated and the Higher Polytechnic Institute José Antonio Echeverría was founded. When the so-called plan A was established in 1977-1978 Hydraulic Engineering had three specializations. During the following years plans B and C and their variants were applied until the present time that e new curricular design is under elaboration (plan D). It must be said that the plan C that started its application in 1990-91 represents the most profound and radical transformation in the field of curricular design seen until this moment. [ABSTRACT FROM AUTHOR]

To keep in mind the influence of the natural gradient of the flow in the aquifer, it is possible to superimpose in a perpendicular plane to the reception structure, the lineal flow toward this with certain flow that will take place in that same plane, corresponding to the lineal natural flow of the aquifer. As a result, the field of flow is represented by certain potential function (Φ) and an stream function (ψ), which are intimately related, it is demonstrated in this paper under the asumptions of non semicilíndrical flow. Likewise, the expressions corresponding of the stagnation point are determined and the position of the dividide line. [ABSTRACT FROM AUTHOR]

The biofilm processes has been profusely used during the last ten years. This has been due to the more and more rigorous standards for wastewater treatment and the necessity of a better use of the space. Biofilm processes include the "submerged fixed bed reactors". Such reactors are characterized by their high buffer capacity as a consequence of the organic load fluctuations originated by the high capacity of adsorption of the biofilm. This paper shows the modeling of an aerated fixed bed submerged reactor at pilot plant scale, for the treatment of a synthetic substrate. An experiment design of 24 was used. Operational variables used were organic matter concentration as COD, hydraulic retention time, packing area and aeration level. [ABSTRACT FROM AUTHOR]