Environmental planning and risk assessments of dams failures.

Dams are one of the main storage facilities in human lives. The population growth rates increasing with times durations, then the demand for water and food is also increasing accordingly and rapidly, and the dams are an important part of the extraction and exploitation cycle. With the increase in the number of dams, the number of accidents related to dam failures has been increased, which has resulted in casualties for humans and serious damage to nature, such as Samarco disaster. Tailing dams are one of the most dangerous types of man-made dams. Due to the multiplicity of accidents that have occurred in this type of dam, most of the research focus is on this type of dam. Much research has been done to find the root causes of these accidents to prevent such tragedies. These factors can be divided into two categories: human and non-human. In connection with human errors, we can mention the use of upstream embankment structure, management mistake, excessive increase of the dam height, lack of investment for tailing management, and structural defects. In relation to non-human factors, we can mention three main categories, which include: cumulative damage (like seepage and multiple earthquakes), geological hazards (like seismic liquefaction, overtopping, non-seismic instability, and foundation subsidence), and unusual weather (like unusual rain). After numerous incidents, humans developed computational methods for risk assessment and risk management and control. There is some stability analyzes methods like Limit Equilibrium Methods, numerical simulation methods, and uncertainty methods. One of the main preventing actions about dam failures is risk screening and monitoring. International organizations related to dams presented 8 steps for monitoring and screening risk like commodity selection, production selection, date selection, wet tailing selection, spatial overlay of ESG risk indicators, application of risk thresholds and this monitoring is done by using 8 indicators including: water, tailings, biodiversity, land uses, native peoples, social vulnerability, political fragility, and approval and permitting. Also, two of the biggest dam failures catastrophes that happened have been investigated and their main causes of these incidents have been reviewed. Finally, the reasons for the success of a dam that remained intact until the end of the operation were compared with the reasons for the failure of two of the broken dams. [ABSTRACT FROM AUTHOR]