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When a dam is built, its safety becomes a constant concern for the owner, the public and for governments. Therefore, continuous observation through routine inspections and safety reviews become necessary. Acting as protectors of public safety, governments and professional organizations save no effort in the promulgation of legislations and laying out guidelines for such inspections and reviews. These issues are discussed here starting with the basic first step of visual inspections by the operators and the follow up of detailed safety reviews by specialists. Careful visual inspections assisted by instrumentation measurements may reveal an early negative issue such as, but not limited to, increased seepage, increased uplift pressure, signs of weakness like cracking in the body of the dam, or dams’ slope sloughing, and even damaged hydraulic control equipment. Documenting and reporting these observation helps in taking remedial measures in good time and may lead to more intensive safety reviews. Suggested check lists for the inspection engineers are given here, but these may be tailored for each dam according to its needs. These lists cover issues common to both embankment and concrete dams, and include other specific issues related to each type of them. Metal equipment take their share by listing such areas as corrosion, fatigue and cracking, tear, and wear and so on. Instrumentation measurements are also given their due consideration by giving brief mention of types of measurements needed and points to be observed in instrumentation control work. Finally, guidelines, rules, and legislations for Dam Safety Reviews are generally discussed giving examples from four countries in the world., Validerad;2020;Nivå 1;2020-09-29 (johcin)

Dam Safety and dam incidents are treated here looked at from the "Human Factors" perspective. An attempt is made to explore these factors as an important drive in impairing dams’ safety and increases their risks. Distinction is drawn between the "Normal Human Caused Incidents" and the "Extraordinary Human Caused Incidents" together with the description of their root origins and subsequent consequences. The first type includes unintentional mistakes, errors and flaws committed by the operators of dams inadvertently, in addition to negligence, lack of experience or overconfidence. Such failings can happen in manual operation of dams, or through the use of their Supervision, Control and Data Acquisition (SCADA) systems as in industrial control system (ICS). They can occur also due to flaws in software or even in the application of information and communication technology (ICT) in remote control operations. As for the second group; the extraordinary human factors, they are defined here as those committed by man with the full understanding of their possible damage. They are done purposely for destabilizing dams after thoughtful and carefully meditated decision making process and they are manifested in acts of war, sabotage and terrorists actions. In this modern age, these acts are characteristics of hackers’ attacks on dam(s) operating systems. This is done through the use of cyberspace by the widespread interconnected digital technology with the accompanying advances in the communication technologies. As such, these technologies have made remote control of such systems possible. Not limited to this, dams remain now, as they were always in the past, the obvious targets in wars and conflicts to inflict losses on the enemy and to use them as weapons, and for terrorism actions for challenging governments. Examples of the aforementioned threats are described with examples given from real cases to elucidate the dangers involved. Lessons to be learned from these incidents are, Validerad;2020;Nivå 1;2020-09-29 (johcin)

The awareness to tailings dam safety monitoring and reviews has increased by the catastrophes resulting from failures of such dams worsened by increasing tailings waste and construction of larger dams. The losses born by the mining industry from high costs of compensations and environmental rehabilitation work have brought this matter into focus. In the present article the need for safety monitoring programs of tailings dam is highlighted and mode of failures and factors leading to them are described. Basic principles of such programs are investigated with all phenomena needing observation described and their impacts explained. As in conventional dams this work is carried out by visual inspections and use of similar methods and instruments. In similar manners in both types of dams’ observation and measurements are done for measuring seepage water quantity and quality, phreatic surface level and pore pressure and total earth pressure values in addition to deformation measurements; and all are done by similar devices and methods such as weirs, piezometers, inclinometers, settlement plates and geodetic surveying. Basic differences between safety monitoring systems of the two types of dam, however, are presented in a tabular form. The continuity of safety monitoring of tailings dams is emphasized not only during the long construction phase but also after that in the abandonment and closure phase which can last indefinitely in order to watch for possible adverse effects on the environment and ecosystem due to the winds eroding and carrying of poisonous tailings contents, in addition to contaminated seepage water entering surface water streams and ground water. Justifications for using real time monitoring systems for recording and transmitting all data to the control center are presented with emphasis given on savings in both labor and time and need for the discovery of warning signs enabling raising earlier the alarm of possible failure or incident and the early taking, Validerad;2020;Nivå 1;2020-09-29 (johcin)

When a dam is built, its safety becomes a constant concern for the owner, the public and for governments. Therefore, continuous observation through routine inspections and safety reviews become necessary. Acting as protectors of public safety, governments and professional organizations save no effort in the promulgation of legislations and laying out guidelines for such inspections and reviews. These issues are discussed here starting with the basic first step of visual inspections by the operators and the follow up of detailed safety reviews by specialists. Careful visual inspections assisted by instrumentation measurements may reveal an early negative issue such as, but not limited to, increased seepage, increased uplift pressure, signs of weakness like cracking in the body of the dam, or dams’ slope sloughing, and even damaged hydraulic control equipment. Documenting and reporting these observation helps in taking remedial measures in good time and may lead to more intensive safety reviews. Suggested check lists for the inspection engineers are given here, but these may be tailored for each dam according to its needs. These lists cover issues common to both embankment and concrete dams, and include other specific issues related to each type of them. Metal equipment take their share by listing such areas as corrosion, fatigue and cracking, tear, and wear and so on. Instrumentation measurements are also given their due consideration by giving brief mention of types of measurements needed and points to be observed in instrumentation control work. Finally, guidelines, rules, and legislations for Dam Safety Reviews are generally discussed giving examples from four countries in the world., Validerad;2020;Nivå 1;2020-09-29 (johcin)

The awareness to tailings dam safety monitoring and reviews has increased by the catastrophes resulting from failures of such dams worsened by increasing tailings waste and construction of larger dams. The losses born by the mining industry from high costs of compensations and environmental rehabilitation work have brought this matter into focus. In the present article the need for safety monitoring programs of tailings dam is highlighted and mode of failures and factors leading to them are described. Basic principles of such programs are investigated with all phenomena needing observation described and their impacts explained. As in conventional dams this work is carried out by visual inspections and use of similar methods and instruments. In similar manners in both types of dams’ observation and measurements are done for measuring seepage water quantity and quality, phreatic surface level and pore pressure and total earth pressure values in addition to deformation measurements; and all are done by similar devices and methods such as weirs, piezometers, inclinometers, settlement plates and geodetic surveying. Basic differences between safety monitoring systems of the two types of dam, however, are presented in a tabular form. The continuity of safety monitoring of tailings dams is emphasized not only during the long construction phase but also after that in the abandonment and closure phase which can last indefinitely in order to watch for possible adverse effects on the environment and ecosystem due to the winds eroding and carrying of poisonous tailings contents, in addition to contaminated seepage water entering surface water streams and ground water. Justifications for using real time monitoring systems for recording and transmitting all data to the control center are presented with emphasis given on savings in both labor and time and need for the discovery of warning signs enabling raising earlier the alarm of possible failure or incident and the early taking, Validerad;2020;Nivå 1;2020-09-29 (johcin)

Dam Safety and dam incidents are treated here looked at from the "Human Factors" perspective. An attempt is made to explore these factors as an important drive in impairing dams’ safety and increases their risks. Distinction is drawn between the "Normal Human Caused Incidents" and the "Extraordinary Human Caused Incidents" together with the description of their root origins and subsequent consequences. The first type includes unintentional mistakes, errors and flaws committed by the operators of dams inadvertently, in addition to negligence, lack of experience or overconfidence. Such failings can happen in manual operation of dams, or through the use of their Supervision, Control and Data Acquisition (SCADA) systems as in industrial control system (ICS). They can occur also due to flaws in software or even in the application of information and communication technology (ICT) in remote control operations. As for the second group; the extraordinary human factors, they are defined here as those committed by man with the full understanding of their possible damage. They are done purposely for destabilizing dams after thoughtful and carefully meditated decision making process and they are manifested in acts of war, sabotage and terrorists actions. In this modern age, these acts are characteristics of hackers’ attacks on dam(s) operating systems. This is done through the use of cyberspace by the widespread interconnected digital technology with the accompanying advances in the communication technologies. As such, these technologies have made remote control of such systems possible. Not limited to this, dams remain now, as they were always in the past, the obvious targets in wars and conflicts to inflict losses on the enemy and to use them as weapons, and for terrorism actions for challenging governments. Examples of the aforementioned threats are described with examples given from real cases to elucidate the dangers involved. Lessons to be learned from these incidents are, Validerad;2020;Nivå 1;2020-09-29 (johcin)

Dam safety concerns do not stop at site selection, or the design and construction stages of a dam, but continue throughout its whole life. Seeing to safety issues of any dam is done by following up its behavior through visual observation supplemented and enriched by data collection from all the devices installed on or implanted in a dam to follow its reactions to the forces and conditions in action. Analysis of the accumulated data will show the safety level and the need or, otherwise, of any remedial works. Using measuring devices to quantifying seepage conditions at any dam and correlating this with water levels’ fluctuations is the first main issue that concerns dam safety. Added to this, measurement of pore water and total earth pressure in earthfill dams, temperature measurements in concrete dams, uplift and displacement measurements, and measurements of stresses and strains can all give good pictures of what is happening inside the dam and/or its foundation in both types of dams. In the following work, a summary of typical instrumentations and monitoring used in evaluating causes of common problems is given. Moreover, requirements for good instrumentation program are explained and the methods of data collection, whether manual, or use of stand-alone loggers and real-time monitoring networks are touched upon. The various devices in current use are described in more details. Actual examples of monitoring systems in existing dams are presented to show the value and importance of these systems to the safety of these dams., Validerad;2020;Nivå 1;2020-09-29 (johcin)

Seismic instrumentation of dams and reservoirs sites is accepted today as a valuable tool to understand significant seismic hazards facing existing dams or future planed dams. With the advent of digital seismic accelerometers and recorders, it can now be used today as an integral part of dam safety monitoring systems. Outputs of these instruments help in understanding the dynamic response of dams during earthquake, assessing the damage caused by such events and determining required upgrading works necessary for existing dams and designing of safer dams in the future. Measuring and recording by strong motion seismographs covers the induced Peak Ground Acceleration (PGA), velocity and displacement recorded on time scale to indicate the intensity and frequency of ground vibration at the site during seismic events. Seismometers for such measurements and recordings have undergone considerable evolution and there exist today a variety of these instruments with high degree of refinement which can even provide for remote sensing. In this work, this development is outlined and examples of seismic instrumentation in strategic dams are described. Damages to actual concrete and embankment dams of various types are described indicating the associated PGAs experienced during the mentioned earthquakes. Damages in the form of cracking, increased seepage, additional settlements and displacements are described to show type and extent of possible consequences of such events on dams. The reached conclusion is that seismic instrumentation systems are desirable and highly recommendable for all types of dams; existing and future ones and their high cost is justified by the service they provide., Validerad;2020;Nivå 1;2020-09-29 (johcin)

The use of geophysical methods in dam sites investigations and safety monitory has proved their good value and versatility in many earthfill dam sites as early as the 1920s. In the following years great development has occurred in the methods, application procedures and tools used. They may be considered today as good ways for carrying out observation tasks on existing dams in non-intrusive and much faster and cheaper ways than the traditional geotechnical methods. It is possible using them to discover anomalies in the dam body or its foundation at an early stage and allowing quick intervention repair works. These methods seek to register and present variations in the basic geotechnical material properties in dams such as; bulk density, moisture content, elasticity, mechanical properties of rocks, electrical resistivity and mineralogy and magnetic properties and so forth. Such variations can indicate increasing seepage flow, progression in cracks’ sizes, formation of voids, caverns and other instability manifestations. Depending on how any investigation is carried out and the targeted anomaly, there is now selection of these methods such as: Electromagnetic Profiling (EM), Electrical Resistivity Tomography (ERT), Self- Potential (SP), Ground Penetration Radar (GPR), variety of Seismic Methods (SM) which can be applied using such equipment as in Seismic refraction, Seismic Reflection, Multi Analysis of Rayleigh surface waves (MASW) instruments, or using Refraction Micrometer (ReMi), macro-gravity method, and Cross-Hole Seismic Tomography. In addition, Temperature Measurements and other less used methods can be used like Microgravity measurement, Magnetic Profiling and Radio Magnetotelluric methods. An attempt is made here to cover the details of these methods, their advantages and limitations and to prove their usefulness in many dam sites all over the world. One observed issue is their adaptability to embankment dams more than to concrete dams and their popularity f, Validerad;2020;Nivå 1;2020-09-29 (johcin)

Sedimentation of reservoirs has its negative impacts on dams, first by reducing useful storage, altering the benefit/cost ratio originally calculated for the dam, and second by reducing the dams’ capacity for flood routing; increasing flooding hazards on the dam itself and for the downstream. More problems can be created by sediments and floating debris during floods on outlet structures by clogging them and thus creating dangerous situations, or damage trash screens leading to even more problems. If these debris and coarse sediments are allowed in, then they may damage dam structures such as gates, spillways intakes in addition to chutes, stilling basins and power penstocks by the mechanical abrasion impacts of such sediments on them. Frequent inspections, especially after floods must be made to ensure proper functioning of such structure and take actions for reducing the damage. In small reservoirs, dredging; although it adds to maintenance cost, may ease the problem, but in very large reservoirs, this may prove unpractical. Designers, therefore, have a duty to consider sedimentation problem seriously in the initial stages of design by: checking the anticipated accumulation of sediments, allowing enough storage free from siltation, foreseeing their negative impacts on intakes and outlet structures and taking design measures to reduce these impacts. At the same time, dam stability calculations shall have to provision for the anticipated new conditions of silting up at the face of the dam. Operators of dams, on the other hand, shall have to keep open eyes for all the negative issues created by sediments and floating debris, repairing damages caused by them and take measures to reduce their impacts in the future., Validerad;2020;Nivå 1;2020-09-29 (johcin)

Seismic instrumentation of dams and reservoirs sites is accepted today as a valuable tool to understand significant seismic hazards facing existing dams or future planed dams. With the advent of digital seismic accelerometers and recorders, it can now be used today as an integral part of dam safety monitoring systems. Outputs of these instruments help in understanding the dynamic response of dams during earthquake, assessing the damage caused by such events and determining required upgrading works necessary for existing dams and designing of safer dams in the future. Measuring and recording by strong motion seismographs covers the induced Peak Ground Acceleration (PGA), velocity and displacement recorded on time scale to indicate the intensity and frequency of ground vibration at the site during seismic events. Seismometers for such measurements and recordings have undergone considerable evolution and there exist today a variety of these instruments with high degree of refinement which can even provide for remote sensing. In this work, this development is outlined and examples of seismic instrumentation in strategic dams are described. Damages to actual concrete and embankment dams of various types are described indicating the associated PGAs experienced during the mentioned earthquakes. Damages in the form of cracking, increased seepage, additional settlements and displacements are described to show type and extent of possible consequences of such events on dams. The reached conclusion is that seismic instrumentation systems are desirable and highly recommendable for all types of dams; existing and future ones and their high cost is justified by the service they provide., Validerad;2020;Nivå 1;2020-09-29 (johcin)

The use of geophysical methods in dam sites investigations and safety monitory has proved their good value and versatility in many earthfill dam sites as early as the 1920s. In the following years great development has occurred in the methods, application procedures and tools used. They may be considered today as good ways for carrying out observation tasks on existing dams in non-intrusive and much faster and cheaper ways than the traditional geotechnical methods. It is possible using them to discover anomalies in the dam body or its foundation at an early stage and allowing quick intervention repair works. These methods seek to register and present variations in the basic geotechnical material properties in dams such as; bulk density, moisture content, elasticity, mechanical properties of rocks, electrical resistivity and mineralogy and magnetic properties and so forth. Such variations can indicate increasing seepage flow, progression in cracks’ sizes, formation of voids, caverns and other instability manifestations. Depending on how any investigation is carried out and the targeted anomaly, there is now selection of these methods such as: Electromagnetic Profiling (EM), Electrical Resistivity Tomography (ERT), Self- Potential (SP), Ground Penetration Radar (GPR), variety of Seismic Methods (SM) which can be applied using such equipment as in Seismic refraction, Seismic Reflection, Multi Analysis of Rayleigh surface waves (MASW) instruments, or using Refraction Micrometer (ReMi), macro-gravity method, and Cross-Hole Seismic Tomography. In addition, Temperature Measurements and other less used methods can be used like Microgravity measurement, Magnetic Profiling and Radio Magnetotelluric methods. An attempt is made here to cover the details of these methods, their advantages and limitations and to prove their usefulness in many dam sites all over the world. One observed issue is their adaptability to embankment dams more than to concrete dams and their popularity f, Validerad;2020;Nivå 1;2020-09-29 (johcin)

Sedimentation of reservoirs has its negative impacts on dams, first by reducing useful storage, altering the benefit/cost ratio originally calculated for the dam, and second by reducing the dams’ capacity for flood routing; increasing flooding hazards on the dam itself and for the downstream. More problems can be created by sediments and floating debris during floods on outlet structures by clogging them and thus creating dangerous situations, or damage trash screens leading to even more problems. If these debris and coarse sediments are allowed in, then they may damage dam structures such as gates, spillways intakes in addition to chutes, stilling basins and power penstocks by the mechanical abrasion impacts of such sediments on them. Frequent inspections, especially after floods must be made to ensure proper functioning of such structure and take actions for reducing the damage. In small reservoirs, dredging; although it adds to maintenance cost, may ease the problem, but in very large reservoirs, this may prove unpractical. Designers, therefore, have a duty to consider sedimentation problem seriously in the initial stages of design by: checking the anticipated accumulation of sediments, allowing enough storage free from siltation, foreseeing their negative impacts on intakes and outlet structures and taking design measures to reduce these impacts. At the same time, dam stability calculations shall have to provision for the anticipated new conditions of silting up at the face of the dam. Operators of dams, on the other hand, shall have to keep open eyes for all the negative issues created by sediments and floating debris, repairing damages caused by them and take measures to reduce their impacts in the future., Validerad;2020;Nivå 1;2020-09-29 (johcin)

Dam safety concerns do not stop at site selection, or the design and construction stages of a dam, but continue throughout its whole life. Seeing to safety issues of any dam is done by following up its behavior through visual observation supplemented and enriched by data collection from all the devices installed on or implanted in a dam to follow its reactions to the forces and conditions in action. Analysis of the accumulated data will show the safety level and the need or, otherwise, of any remedial works. Using measuring devices to quantifying seepage conditions at any dam and correlating this with water levels’ fluctuations is the first main issue that concerns dam safety. Added to this, measurement of pore water and total earth pressure in earthfill dams, temperature measurements in concrete dams, uplift and displacement measurements, and measurements of stresses and strains can all give good pictures of what is happening inside the dam and/or its foundation in both types of dams. In the following work, a summary of typical instrumentations and monitoring used in evaluating causes of common problems is given. Moreover, requirements for good instrumentation program are explained and the methods of data collection, whether manual, or use of stand-alone loggers and real-time monitoring networks are touched upon. The various devices in current use are described in more details. Actual examples of monitoring systems in existing dams are presented to show the value and importance of these systems to the safety of these dams., Validerad;2020;Nivå 1;2020-09-29 (johcin)

When a dam is built, its safety becomes a constant concern for the owner, the public and for governments. Therefore, continuous observation through routine inspections and safety reviews become necessary. Acting as protectors of public safety, governments and professional organizations save no effort in the promulgation of legislations and laying out guidelines for such inspections and reviews. These issues are discussed here starting with the basic first step of visual inspections by the operators and the follow up of detailed safety reviews by specialists. Careful visual inspections assisted by instrumentation measurements may reveal an early negative issue such as, but not limited to, increased seepage, increased uplift pressure, signs of weakness like cracking in the body of the dam, or dams’ slope sloughing, and even damaged hydraulic control equipment. Documenting and reporting these observation helps in taking remedial measures in good time and may lead to more intensive safety reviews. Suggested check lists for the inspection engineers are given here, but these may be tailored for each dam according to its needs. These lists cover issues common to both embankment and concrete dams, and include other specific issues related to each type of them. Metal equipment take their share by listing such areas as corrosion, fatigue and cracking, tear, and wear and so on. Instrumentation measurements are also given their due consideration by giving brief mention of types of measurements needed and points to be observed in instrumentation control work. Finally, guidelines, rules, and legislations for Dam Safety Reviews are generally discussed giving examples from four countries in the world., Validerad;2020;Nivå 1;2020-09-29 (johcin)

Dam Safety and dam incidents are treated here looked at from the "Human Factors" perspective. An attempt is made to explore these factors as an important drive in impairing dams’ safety and increases their risks. Distinction is drawn between the "Normal Human Caused Incidents" and the "Extraordinary Human Caused Incidents" together with the description of their root origins and subsequent consequences. The first type includes unintentional mistakes, errors and flaws committed by the operators of dams inadvertently, in addition to negligence, lack of experience or overconfidence. Such failings can happen in manual operation of dams, or through the use of their Supervision, Control and Data Acquisition (SCADA) systems as in industrial control system (ICS). They can occur also due to flaws in software or even in the application of information and communication technology (ICT) in remote control operations. As for the second group; the extraordinary human factors, they are defined here as those committed by man with the full understanding of their possible damage. They are done purposely for destabilizing dams after thoughtful and carefully meditated decision making process and they are manifested in acts of war, sabotage and terrorists actions. In this modern age, these acts are characteristics of hackers’ attacks on dam(s) operating systems. This is done through the use of cyberspace by the widespread interconnected digital technology with the accompanying advances in the communication technologies. As such, these technologies have made remote control of such systems possible. Not limited to this, dams remain now, as they were always in the past, the obvious targets in wars and conflicts to inflict losses on the enemy and to use them as weapons, and for terrorism actions for challenging governments. Examples of the aforementioned threats are described with examples given from real cases to elucidate the dangers involved. Lessons to be learned from these incidents are, Validerad;2020;Nivå 1;2020-09-29 (johcin)

The awareness to tailings dam safety monitoring and reviews has increased by the catastrophes resulting from failures of such dams worsened by increasing tailings waste and construction of larger dams. The losses born by the mining industry from high costs of compensations and environmental rehabilitation work have brought this matter into focus. In the present article the need for safety monitoring programs of tailings dam is highlighted and mode of failures and factors leading to them are described. Basic principles of such programs are investigated with all phenomena needing observation described and their impacts explained. As in conventional dams this work is carried out by visual inspections and use of similar methods and instruments. In similar manners in both types of dams’ observation and measurements are done for measuring seepage water quantity and quality, phreatic surface level and pore pressure and total earth pressure values in addition to deformation measurements; and all are done by similar devices and methods such as weirs, piezometers, inclinometers, settlement plates and geodetic surveying. Basic differences between safety monitoring systems of the two types of dam, however, are presented in a tabular form. The continuity of safety monitoring of tailings dams is emphasized not only during the long construction phase but also after that in the abandonment and closure phase which can last indefinitely in order to watch for possible adverse effects on the environment and ecosystem due to the winds eroding and carrying of poisonous tailings contents, in addition to contaminated seepage water entering surface water streams and ground water. Justifications for using real time monitoring systems for recording and transmitting all data to the control center are presented with emphasis given on savings in both labor and time and need for the discovery of warning signs enabling raising earlier the alarm of possible failure or incident and the early taking, Validerad;2020;Nivå 1;2020-09-29 (johcin)

Sedimentation of reservoirs has its negative impacts on dams, first by reducing useful storage, altering the benefit/cost ratio originally calculated for the dam, and second by reducing the dams’ capacity for flood routing; increasing flooding hazards on the dam itself and for the downstream. More problems can be created by sediments and floating debris during floods on outlet structures by clogging them and thus creating dangerous situations, or damage trash screens leading to even more problems. If these debris and coarse sediments are allowed in, then they may damage dam structures such as gates, spillways intakes in addition to chutes, stilling basins and power penstocks by the mechanical abrasion impacts of such sediments on them. Frequent inspections, especially after floods must be made to ensure proper functioning of such structure and take actions for reducing the damage. In small reservoirs, dredging; although it adds to maintenance cost, may ease the problem, but in very large reservoirs, this may prove unpractical. Designers, therefore, have a duty to consider sedimentation problem seriously in the initial stages of design by: checking the anticipated accumulation of sediments, allowing enough storage free from siltation, foreseeing their negative impacts on intakes and outlet structures and taking design measures to reduce these impacts. At the same time, dam stability calculations shall have to provision for the anticipated new conditions of silting up at the face of the dam. Operators of dams, on the other hand, shall have to keep open eyes for all the negative issues created by sediments and floating debris, repairing damages caused by them and take measures to reduce their impacts in the future., Validerad;2020;Nivå 1;2020-09-29 (johcin)

Dam safety concerns do not stop at site selection, or the design and construction stages of a dam, but continue throughout its whole life. Seeing to safety issues of any dam is done by following up its behavior through visual observation supplemented and enriched by data collection from all the devices installed on or implanted in a dam to follow its reactions to the forces and conditions in action. Analysis of the accumulated data will show the safety level and the need or, otherwise, of any remedial works. Using measuring devices to quantifying seepage conditions at any dam and correlating this with water levels’ fluctuations is the first main issue that concerns dam safety. Added to this, measurement of pore water and total earth pressure in earthfill dams, temperature measurements in concrete dams, uplift and displacement measurements, and measurements of stresses and strains can all give good pictures of what is happening inside the dam and/or its foundation in both types of dams. In the following work, a summary of typical instrumentations and monitoring used in evaluating causes of common problems is given. Moreover, requirements for good instrumentation program are explained and the methods of data collection, whether manual, or use of stand-alone loggers and real-time monitoring networks are touched upon. The various devices in current use are described in more details. Actual examples of monitoring systems in existing dams are presented to show the value and importance of these systems to the safety of these dams., Validerad;2020;Nivå 1;2020-09-29 (johcin)

The basins of the Tigris and Euphrates Rivers Cover an area of 917103km2 distributed between Iraq, Turkey, Iran, Syria and Saudi Araba. The population within the basins reaches about 50 million inhabitants. The flow of the two rivers is decreasing with time. This is due to the construction of dams and irrigation projects in the upper parts of the basins and climate change. This has an impact on the quality of water within the two rivers. Iraq being the lowest riparian country is highly effected. Analysis of water quality of the water indicates that the salinity of Euphrates water is increasing with time and on the Syrian- Iraqi borders, it is of unacceptable level where it is higher than what is recommended for Irrigation. The Tigris water quality becomes alarming once the river enters Iraq and at Baghdad, it becomes unsuitable for irrigation. To overcome these problems, riparian countries must cooperate seriously to take measures to improve the quality of water within the two rivers., Validerad;2020;Nivå 1;2019-12-18 (johcin)

The basins of the Tigris and Euphrates Rivers Cover an area of 917103km2 distributed between Iraq, Turkey, Iran, Syria and Saudi Araba. The population within the basins reaches about 50 million inhabitants. The flow of the two rivers is decreasing with time. This is due to the construction of dams and irrigation projects in the upper parts of the basins and climate change. This has an impact on the quality of water within the two rivers. Iraq being the lowest riparian country is highly effected. Analysis of water quality of the water indicates that the salinity of Euphrates water is increasing with time and on the Syrian- Iraqi borders, it is of unacceptable level where it is higher than what is recommended for Irrigation. The Tigris water quality becomes alarming once the river enters Iraq and at Baghdad, it becomes unsuitable for irrigation. To overcome these problems, riparian countries must cooperate seriously to take measures to improve the quality of water within the two rivers., Validerad;2020;Nivå 1;2019-12-18 (johcin)

Dam safety hazards towards human communities have increased tremendously during the last decades. They have resulted from dam safety problems leading to failure and being exasperated by the large losses at downstream areas due to increasing populations and land use. In this work, an attempt is being made to review the procedures being followed to reduces these hazards by improving dams safety standards. Classification of dams by their potential hazards are explained as used today for prioritize remedial actions in various countries of the world. The guiding principles of these classification are indicated and they are based on height of such dams and their storage and linked to the potential damage and harm they can create. Normally such classification and follow up actions are supported by various legislations and regulations issued by the respective governments. Moreover, conventions signed by riparian countries promote cooperation on mitigating safety problems of dams on transboundary rivers. Examples of such legislations and conventions are mentioned. Looking for having safer dams is an objective continually which is being pursued as more dams are needed in the future while existing dams continue to serve their objectives. Therefore, using lessons learned from previous failures is recommended taking the question of loss of life as a main doctrine., Validerad;2020;Nivå 1;2020-06-23 (alebob)

Earthquakes may cause failure or profound damage for dams. Factors contributing to this are, magnitude on the Richter scale, peak horizontal and vertical accelerations, time duration, in addition to the epicentral distance, nature of foundation rock, criteria of the design, and finally, if appropriate type of dam and materials has been used. Extensive lists of dam failures and damaged once are presented with many case histories. Most failed dams were tailing dams or hydraulic fill dams or small earth fill dams, which reflect the weight of the design and construction factors. Embankment dams, normally, are less tolerant to ground shacking than concrete dams. While rockfill and RCC dams have shown good performance. The developments of design methods and criteria are traced here, from the early use of the pseudoptotic method to the more rational dynamic analysis, which is used nowadays making construction of very large safe dams in seismic regions possible. The method adopts peak ground accelerations from anticipated earthquakes as inputs to the analysis which produce a full spectrum of the factor of safety during any considered event. This has led to increased use of seismic instrumentation to produce seismographs of actual events in the free field, and on dams hit by earthquakes for comparison with outputs of this analysis and for future use for similar dams in similar circumstances, and to decide on rehabilitation measures. The safety levels to which any dam is to be designed are defined in terms of the Maximum Credible Earthquake, Safety Evaluation Earthquake, Maximum Design Earthquake and other similar terms. Dam repairs after sustaining earthquake damages are described in real cases and upgrading of older dams to withstand higher expected seismic events are also treated here and supported by case histories., Validerad;2020;Nivå 1;2020-06-23 (alebob)

Dam safety hazards towards human communities have increased tremendously during the last decades. They have resulted from dam safety problems leading to failure and being exasperated by the large losses at downstream areas due to increasing populations and land use. In this work, an attempt is being made to review the procedures being followed to reduces these hazards by improving dams safety standards. Classification of dams by their potential hazards are explained as used today for prioritize remedial actions in various countries of the world. The guiding principles of these classification are indicated and they are based on height of such dams and their storage and linked to the potential damage and harm they can create. Normally such classification and follow up actions are supported by various legislations and regulations issued by the respective governments. Moreover, conventions signed by riparian countries promote cooperation on mitigating safety problems of dams on transboundary rivers. Examples of such legislations and conventions are mentioned. Looking for having safer dams is an objective continually which is being pursued as more dams are needed in the future while existing dams continue to serve their objectives. Therefore, using lessons learned from previous failures is recommended taking the question of loss of life as a main doctrine., Validerad;2020;Nivå 1;2020-06-23 (alebob)

Earthquakes may cause failure or profound damage for dams. Factors contributing to this are, magnitude on the Richter scale, peak horizontal and vertical accelerations, time duration, in addition to the epicentral distance, nature of foundation rock, criteria of the design, and finally, if appropriate type of dam and materials has been used. Extensive lists of dam failures and damaged once are presented with many case histories. Most failed dams were tailing dams or hydraulic fill dams or small earth fill dams, which reflect the weight of the design and construction factors. Embankment dams, normally, are less tolerant to ground shacking than concrete dams. While rockfill and RCC dams have shown good performance. The developments of design methods and criteria are traced here, from the early use of the pseudoptotic method to the more rational dynamic analysis, which is used nowadays making construction of very large safe dams in seismic regions possible. The method adopts peak ground accelerations from anticipated earthquakes as inputs to the analysis which produce a full spectrum of the factor of safety during any considered event. This has led to increased use of seismic instrumentation to produce seismographs of actual events in the free field, and on dams hit by earthquakes for comparison with outputs of this analysis and for future use for similar dams in similar circumstances, and to decide on rehabilitation measures. The safety levels to which any dam is to be designed are defined in terms of the Maximum Credible Earthquake, Safety Evaluation Earthquake, Maximum Design Earthquake and other similar terms. Dam repairs after sustaining earthquake damages are described in real cases and upgrading of older dams to withstand higher expected seismic events are also treated here and supported by case histories., Validerad;2020;Nivå 1;2020-06-23 (alebob)

The Mesopotamian Plain is part of the large Mesopotamia which extends in Iraq and surrounding countries. The plain is almost flat and vast lowland, which has clearly defined physiographic boundaries with the other surrounding physiographic provinces. From the north and east, it is limited by the Low Amplitude Mountainous Province. From the west, the upper part is limited by Al-Jazira Plain, whereas in the lower part by the Western Desert Province. From the south it is limited by the Southern Desert Province. The plain is a huge accumulational geomorphologic unit, where the fluvial, lacustrine, and Aeolian landforms prevail; the fluvial units being the abundant among others. However, estuarine and marine forms also are developed, but restricted to the extreme south-eastern reaches of the plain. Moreover, some erosional landforms are developed in different places, but are not well expressed. In the central eastern part, large alluvial fans are developed with five stages covering vast areas along the Iraqi – Iranian international borders. The geomorphic units are classified according to origin, geomorphic position, and lithology. Some of the significant features are described with some details., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Most of the Mesopotamian Plain is covered by Quaternary sediments among which the flood plain sediments of the Tigris and Euphrates rivers are the most dominant parts. Aeolian sediments; however, also cover considerable areas at different parts of the plain in forms of sand dunes, sand sheets and Nebkhas. The dunes are the most common form and they are creeping as well as sand sheets in vast areas causing desertification. The main reasons causing this is climate change, abandoning of agricultural areas. Salinization is another significant problem in the plain whereby the affected areas are growing in size and the concentration of the salt in the soil, as well as the groundwater is increasing rapidly. The increase in salinization is due to miss- management of water resources, and the increasing salinity of the surface and ground water which due to the use of irrigation water supplied from Al-Tharthar Depression (lake) and the Main Outfall Drain., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain hydrogeologically is a semi-closed basin where most of the groundwater accumulates in the central and southern parts of the plain. However, small part of the groundwater flows out of the basin to the Gulf. This special character has significant effects on the depth and type of the groundwater in the plain. The depth ranges from (<10 – 100)m; however, the depth in the most of the plain ranges from (10 – 20)m. The type of the ground water is mainly salty water with concentrations of (10,000 – 50,000) mg/l; however, in the central part it is even Brine water (> 500,000 mg/l). No fresh groundwater exists in the plain., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain is part of the Mesopotamia which extends for vast area bigger than the plain. The Mesopotamian Plain is covered totally by Quaternary sediments among which the fluvial origin is the most prevailing and more specifically the flood plain sediments. The flood plain sediments are Holocene in age, whereas the Pleistocene sediments are restricted to alluvial fan sediments and river terraces. The flood plain sediments cover majority of the Mesopotamian Plain, whereas the alluvial sediments are restricted to the northern eastern, western and southern peripheral parts only. The extreme south-eastern part is covered by the tidal flat and sabkha sediments. Marshes and shallow depressions are also covered by Holocene sediments which are contaminated by Aeolian sediments. However, Aeolian sediments occur in different forms; among them are the sand dunes, sand sheets and Nebkhas. The distal parts of the alluvial fan sediments interfinger with the sheet run off sediments which in turn interfinger with the flood plain sediments. Moreover, the alluvial fan sediments interfinger laterally by other fan sediments or merge laterally together to form Bajada., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain is a vast almost flat plain which descends in elevation towards southeast until it reaches the sea level along the Gulf shore. The plain covers the central part of Iraq; it is covered totally by different type of Quaternary sediments. Among those sediments, the fluvial flood plain sediments of the Tigris and Euphrates rivers with their distributaries are the most prevailing. The two river merge together to form the Shatt (River) Al-Arab which drains into the Gulf. The extensions of the Gulf are a matter of debit, especially between two groups of researchers: geologists and archeologists and even within the same group. We have presented different opinions which have dealt with the Gulf extensions, since the beginning of the last century and until most recent studies. From the presented and discussed data, it is clear that there is no clear and sound data which confirms the actual extensions of the Gulf during Holocene and even Late Pleistocene, Validerad;2020;Nivå 1;2020-04-24 (marisr)

Mesopotamia is a land where floods have occurred very frequently. Many destructive floods had been registered by historians, who noted also the food control schemes used in those times. Over history, many structures were built and managed, but this work was taken up again by the General Directorate of Irrigation which was formed in 1917 to manage floods and reduce as much as possible losses, in addition to the development of irrigation works. Plans were made to build a sophisticated flood control and protection system. Several projects were proposed, and since the 1950s they were successfully implemented. Many multipurpose dams were built to mitigate flood conditions in addition to their other functions, such as Mosul Dam, Dokan Dam, Derbendikhan Dam and Haditha Dam. Other projects which were solely planned for flood protection include developing and using natural depressions such as Habbaniyah Lake on the Euphrates River and Tharthar Lake on the Tigris River, to protect Mesopotamia from floods. Moreover, the southern marshes in lower Mesopotamia may be utilized for flood protection. This paper deals only with these natural depressions leaving the dams at the time being., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The main material with economic potential in the plain is the clay. The clay is used for brick production; either with modernized technology or primitive industry. It is also used for cement industry. The creeping sand dunes have decreasing the potentiality of the clay for both uses. Salt is another economic material which is produced from Smawa saltern and other small primitive salt basins. The subsurface oil fields in the plain remain as the main source with economic potential., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Since early civilization and the farmers in Mesopotamia are suffering from the soil salinity. This problem had caused the transfer of power from the Sumerians to the Babylonians in ancient history. Great efforts and research have been made since the beginning of the 20th century to overcome this salinity problem. Experts have concluded that the main reason for salinity is the salt content of irrigation water and the shallow saline groundwater derived from the irrigation activities. General schemes were planned, which involve building a new system of drains in parallel to the irrigation network. The backbone of the drainage system in Mesopotamia is the Main Outfall Drain (MOD). Large works such as Musayab Main Drain, Main Outfall Drain, Great Gharraf Drain, East Euphrates Drain were implemented, but there are still large needs for much more work to be done., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Euphrates River is one of the two rivers where the civilization and irrigation had started, many major irrigation systems are still operating for centuries. The most important advancement of irrigation within this area happened after 1920s, where new structures were constructed, new canals excavated, new pumps installed, and salt affected lands were reclaimed. The major irrigation projects in along the reach of Euphrates within Mesopotamia are, Great Abu Ghraib, Great Musayab, Hilla Branch projects, Kifl-Shiniafiyah, in addition to many other medium and small size projects. Besides, some important Barrages have been built for controlling water levels of the Euphrates for proper operation, such as Fallujah and Hindiya Barrages. There is a great need for more reclamation in the lower parts of this territory, as well alternatives are needed to avoid discharging saline drainage water to the Euphrates in some projects., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Several irrigation systems have been built at Tigris River basin within Mesopotamia plain. The upper part of Tigris at Mesopotamia is extensively exploited, and several major projects were constructed since the 1970s. These are Ishaqi, Khalis, Diyala Combined Reach, Nahrawan, Dujailya and Dalmaj. Other projects were partially developed, which are Middle-Tigris, Gharraf projects, Great Amarah and KutButaira. The important barrages in this part are Kut Barrage, as well, as the barrages in Amarah area which are of vital importance for irrigation and navigation. Shaat Al-Arab is one of the most important waterways in Iraq. This river has been suffered from water scarcity and riparian countries actions. Solutions for adaptation to adapt the situation were studied and planned carefully, but still there is need for more work to cope with the situation in Basra area., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain is a part of the Mesopotamia Foredeep of the Zagros Foreland Basin and is a part of the Zagros Fold – Thrust Belt. The plain covers the central part of Iraq and extends south eastwards. It is a large continuously subsiding basin since the Upper Miocene (11.62 Ma). The plain is covered by thick Quaternary sediments of the Tigris and Euphrates rivers with their tributaries and distributaries. Therefore, the plain shows no structural features on the surface, except a main fault escarpment that extends from south of Al-Najaf city to south of Nasiriya city representing part of Abu Jir Active Fault Zone. However, the rolling topography, in the northern parts of the plain indicates subsurface anticlines that are still growing up, such as Balad, Samarra, Tikrit and Baiji anticlines. Moreover, many buried subsurface anticlines are present in different parts of the plain. All are growing anticlines and have caused continuous shift to the Tigris and Euphrates River and their distributaries indicating Neotectonic activities. The minimum and maximum subsidence amounts in the plain are zero and – 2500 m, respectively., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The main material with economic potential in the plain is the clay. The clay is used for brick production; either with modernized technology or primitive industry. It is also used for cement industry. The creeping sand dunes have decreasing the potentiality of the clay for both uses. Salt is another economic material which is produced from Smawa saltern and other small primitive salt basins. The subsurface oil fields in the plain remain as the main source with economic potential., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Since early civilization and the farmers in Mesopotamia are suffering from the soil salinity. This problem had caused the transfer of power from the Sumerians to the Babylonians in ancient history. Great efforts and research have been made since the beginning of the 20th century to overcome this salinity problem. Experts have concluded that the main reason for salinity is the salt content of irrigation water and the shallow saline groundwater derived from the irrigation activities. General schemes were planned, which involve building a new system of drains in parallel to the irrigation network. The backbone of the drainage system in Mesopotamia is the Main Outfall Drain (MOD). Large works such as Musayab Main Drain, Main Outfall Drain, Great Gharraf Drain, East Euphrates Drain were implemented, but there are still large needs for much more work to be done., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Mesopotamia is a land where floods have occurred very frequently. Many destructive floods had been registered by historians, who noted also the food control schemes used in those times. Over history, many structures were built and managed, but this work was taken up again by the General Directorate of Irrigation which was formed in 1917 to manage floods and reduce as much as possible losses, in addition to the development of irrigation works. Plans were made to build a sophisticated flood control and protection system. Several projects were proposed, and since the 1950s they were successfully implemented. Many multipurpose dams were built to mitigate flood conditions in addition to their other functions, such as Mosul Dam, Dokan Dam, Derbendikhan Dam and Haditha Dam. Other projects which were solely planned for flood protection include developing and using natural depressions such as Habbaniyah Lake on the Euphrates River and Tharthar Lake on the Tigris River, to protect Mesopotamia from floods. Moreover, the southern marshes in lower Mesopotamia may be utilized for flood protection. This paper deals only with these natural depressions leaving the dams at the time being., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain is part of the large Mesopotamia which extends in Iraq and surrounding countries. The plain is almost flat and vast lowland, which has clearly defined physiographic boundaries with the other surrounding physiographic provinces. From the north and east, it is limited by the Low Amplitude Mountainous Province. From the west, the upper part is limited by Al-Jazira Plain, whereas in the lower part by the Western Desert Province. From the south it is limited by the Southern Desert Province. The plain is a huge accumulational geomorphologic unit, where the fluvial, lacustrine, and Aeolian landforms prevail; the fluvial units being the abundant among others. However, estuarine and marine forms also are developed, but restricted to the extreme south-eastern reaches of the plain. Moreover, some erosional landforms are developed in different places, but are not well expressed. In the central eastern part, large alluvial fans are developed with five stages covering vast areas along the Iraqi – Iranian international borders. The geomorphic units are classified according to origin, geomorphic position, and lithology. Some of the significant features are described with some details., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Several irrigation systems have been built at Tigris River basin within Mesopotamia plain. The upper part of Tigris at Mesopotamia is extensively exploited, and several major projects were constructed since the 1970s. These are Ishaqi, Khalis, Diyala Combined Reach, Nahrawan, Dujailya and Dalmaj. Other projects were partially developed, which are Middle-Tigris, Gharraf projects, Great Amarah and KutButaira. The important barrages in this part are Kut Barrage, as well, as the barrages in Amarah area which are of vital importance for irrigation and navigation. Shaat Al-Arab is one of the most important waterways in Iraq. This river has been suffered from water scarcity and riparian countries actions. Solutions for adaptation to adapt the situation were studied and planned carefully, but still there is need for more work to cope with the situation in Basra area., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain is part of the Mesopotamia which extends for vast area bigger than the plain. The Mesopotamian Plain is covered totally by Quaternary sediments among which the fluvial origin is the most prevailing and more specifically the flood plain sediments. The flood plain sediments are Holocene in age, whereas the Pleistocene sediments are restricted to alluvial fan sediments and river terraces. The flood plain sediments cover majority of the Mesopotamian Plain, whereas the alluvial sediments are restricted to the northern eastern, western and southern peripheral parts only. The extreme south-eastern part is covered by the tidal flat and sabkha sediments. Marshes and shallow depressions are also covered by Holocene sediments which are contaminated by Aeolian sediments. However, Aeolian sediments occur in different forms; among them are the sand dunes, sand sheets and Nebkhas. The distal parts of the alluvial fan sediments interfinger with the sheet run off sediments which in turn interfinger with the flood plain sediments. Moreover, the alluvial fan sediments interfinger laterally by other fan sediments or merge laterally together to form Bajada., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Most of the Mesopotamian Plain is covered by Quaternary sediments among which the flood plain sediments of the Tigris and Euphrates rivers are the most dominant parts. Aeolian sediments; however, also cover considerable areas at different parts of the plain in forms of sand dunes, sand sheets and Nebkhas. The dunes are the most common form and they are creeping as well as sand sheets in vast areas causing desertification. The main reasons causing this is climate change, abandoning of agricultural areas. Salinization is another significant problem in the plain whereby the affected areas are growing in size and the concentration of the salt in the soil, as well as the groundwater is increasing rapidly. The increase in salinization is due to miss- management of water resources, and the increasing salinity of the surface and ground water which due to the use of irrigation water supplied from Al-Tharthar Depression (lake) and the Main Outfall Drain., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain hydrogeologically is a semi-closed basin where most of the groundwater accumulates in the central and southern parts of the plain. However, small part of the groundwater flows out of the basin to the Gulf. This special character has significant effects on the depth and type of the groundwater in the plain. The depth ranges from (<10 – 100)m; however, the depth in the most of the plain ranges from (10 – 20)m. The type of the ground water is mainly salty water with concentrations of (10,000 – 50,000) mg/l; however, in the central part it is even Brine water (> 500,000 mg/l). No fresh groundwater exists in the plain., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Euphrates River is one of the two rivers where the civilization and irrigation had started, many major irrigation systems are still operating for centuries. The most important advancement of irrigation within this area happened after 1920s, where new structures were constructed, new canals excavated, new pumps installed, and salt affected lands were reclaimed. The major irrigation projects in along the reach of Euphrates within Mesopotamia are, Great Abu Ghraib, Great Musayab, Hilla Branch projects, Kifl-Shiniafiyah, in addition to many other medium and small size projects. Besides, some important Barrages have been built for controlling water levels of the Euphrates for proper operation, such as Fallujah and Hindiya Barrages. There is a great need for more reclamation in the lower parts of this territory, as well alternatives are needed to avoid discharging saline drainage water to the Euphrates in some projects., Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain is a vast almost flat plain which descends in elevation towards southeast until it reaches the sea level along the Gulf shore. The plain covers the central part of Iraq; it is covered totally by different type of Quaternary sediments. Among those sediments, the fluvial flood plain sediments of the Tigris and Euphrates rivers with their distributaries are the most prevailing. The two river merge together to form the Shatt (River) Al-Arab which drains into the Gulf. The extensions of the Gulf are a matter of debit, especially between two groups of researchers: geologists and archeologists and even within the same group. We have presented different opinions which have dealt with the Gulf extensions, since the beginning of the last century and until most recent studies. From the presented and discussed data, it is clear that there is no clear and sound data which confirms the actual extensions of the Gulf during Holocene and even Late Pleistocene, Validerad;2020;Nivå 1;2020-04-24 (marisr)

The Mesopotamian Plain is a part of the Mesopotamia Foredeep of the Zagros Foreland Basin and is a part of the Zagros Fold – Thrust Belt. The plain covers the central part of Iraq and extends south eastwards. It is a large continuously subsiding basin since the Upper Miocene (11.62 Ma). The plain is covered by thick Quaternary sediments of the Tigris and Euphrates rivers with their tributaries and distributaries. Therefore, the plain shows no structural features on the surface, except a main fault escarpment that extends from south of Al-Najaf city to south of Nasiriya city representing part of Abu Jir Active Fault Zone. However, the rolling topography, in the northern parts of the plain indicates subsurface anticlines that are still growing up, such as Balad, Samarra, Tikrit and Baiji anticlines. Moreover, many buried subsurface anticlines are present in different parts of the plain. All are growing anticlines and have caused continuous shift to the Tigris and Euphrates River and their distributaries indicating Neotectonic activities. The minimum and maximum subsidence amounts in the plain are zero and – 2500 m, respectively., Validerad;2020;Nivå 1;2020-04-24 (marisr)

Climate change is affecting the hydrological cycle all over the World. The effect on arid and semi-arid regions is relatively more. The Middle East and North Africa region is one of the biggest hyper-arid, semi-arid and arid zones in the world where the long-term average precipitation does not exceed 166mm per year. The Tigris and Euphrates basins are located within the northern part of the Middle East. Future projections indicate the considerable reduction in water resources as a result of drought and population growth. North Atlantic Oscillation (NAO) is responsible for the change in climate over the Tigris and Euphrates basins. This is causing a decrease in rainfall and a consequence decrease in the flow of the rivers. In addition, the temperature is increasing. All these variables are causing sea level rise, increasing dust storms and deletion of groundwater resources. It is believed that quick actions are required to minimize the effect of climate change. This includes prudent water resources planning and good regional cooperation., Validerad;2020;Nivå 1;2019-12-18 (johcin)

Climate change is affecting the hydrological cycle all over the World. The effect on arid and semi-arid regions is relatively more. The Middle East and North Africa region is one of the biggest hyper-arid, semi-arid and arid zones in the world where the long-term average precipitation does not exceed 166mm per year. The Tigris and Euphrates basins are located within the northern part of the Middle East. Future projections indicate the considerable reduction in water resources as a result of drought and population growth. North Atlantic Oscillation (NAO) is responsible for the change in climate over the Tigris and Euphrates basins. This is causing a decrease in rainfall and a consequence decrease in the flow of the rivers. In addition, the temperature is increasing. All these variables are causing sea level rise, increasing dust storms and deletion of groundwater resources. It is believed that quick actions are required to minimize the effect of climate change. This includes prudent water resources planning and good regional cooperation., Validerad;2020;Nivå 1;2019-12-18 (johcin)

Dam safety hazards towards human communities have increased tremendously during the last decades. They have resulted from dam safety problems leading to failure and being exasperated by the large losses at downstream areas due to increasing populations and land use. In this work, an attempt is being made to review the procedures being followed to reduces these hazards by improving dams safety standards. Classification of dams by their potential hazards are explained as used today for prioritize remedial actions in various countries of the world. The guiding principles of these classification are indicated and they are based on height of such dams and their storage and linked to the potential damage and harm they can create. Normally such classification and follow up actions are supported by various legislations and regulations issued by the respective governments. Moreover, conventions signed by riparian countries promote cooperation on mitigating safety problems of dams on transboundary rivers. Examples of such legislations and conventions are mentioned. Looking for having safer dams is an objective continually which is being pursued as more dams are needed in the future while existing dams continue to serve their objectives. Therefore, using lessons learned from previous failures is recommended taking the question of loss of life as a main doctrine., Validerad;2020;Nivå 1;2020-06-23 (alebob)