environmental, social and economic impacts of dam construction in khorasan razavi province (case study of bar dam in neyshabur)

1. introduction any development with any quantity or quality degree has particular environmental impacts. human manipulation in natural environment does not necessarily mean making changes in initial environment. continuity of human action in the changing natural conditions, which could eventually disrupt the balance of existing environment or causes unintended and unforeseen consequences as currently human societies have been facing this problem. obviously once the idea of construction comes until the project operation, a long and tough way must be passed over. environmental considerations in all phases of the project are major issues that must be considered. this includes the entire process including design, implementation and even scheme exploitation. if human reactions and environmental interactions are assessed in the form of construction projects practices, environmental power and its potential will be revealed by initial recognition. importance and dimensions of negative effects can be achieved by using modern methods. based on the findings, rules can be implemented to reduce the adverse effects and to manage the negative effects. in recent decades, many countries, including iran, in order to reduce problems caused by dehydration and to prevent crisis put a massive investment in water sector. unfortunately, evaluations and studies conducted in the past decade on the physical structure based on rivers and nation and international level approve existing issues and problems in all dimensions, particularly sea water resources management or dam's water and modern water distribution networks. in this regard, the projects implemented and proposals examination using preliminary studies as documentary confirms the difficulties existence in economical, ecological, and especially social-management dimensions. in some of these projects lack of expected goals achievement including improving beneficiaries social and economic conditions, the relative balance between supply and demand for water resources or agricultural prospered are effective and have caused negative reactions among beneficiaries. present study tries to examine impacts resulted by huge investments (physical structures) in constructing bar-dam located in neyshabur. therefore, social, economic and environmental (ecological) dimensions at the basin level of neyshabur bar dam in khorasan razavi were considered. since economic self-sufficiency has a particular importance, and given that the crisis of water and dehydration is one of the major and basic public concerns, water storage and flood water flow control are of cases that involved water engineers and experts. therefore, increase in water supply and flood and water flow control through the dam construction are always recognized the fundamental measures. 2. study area one of the main objectives of bar dam construction is supplying part of the required drinking water of neyshabur county. the special concentration on the neyshabur is because the county is special in culture and geopolitical position. in addition, increasing rural migration to the cities and also due to the development of the town, surrounding villages are connected to neyshabur and are using urban water distribution network and other utilities raise more concerns on the county. the sum of these factors has led county to water shortage, especially in the summer. due to the need for water supply to firoozeh (bozghan) and neyshabur cities and also industrial needs of khorasan steel complex and etc., bar dam construction and related facilities to meet these needs and optimal use of existing potential, regional water resources have been considered as a national and regional policies. this study attempts to answer the issues and questions for the bar-dam. the research method in this study will be descriptive – analytical. due to recent defects of available documents statistics, collecting data and required information will be carried out as documentary. required information of bar dam environmental impacts assessment project is extracted. 3. material and methods regarding impact assessment of development projects implementation, several methods and procedures have been devised and used that considering intended purposes, have different structures. to assess bar dam environmental impact, a leopold two-dimensional matrix is used which in one dimension, environment various options comes that will be affected and in other dimension, different steps and phases of project (construction and operation) are discussed. the virtues of this matrix are summarizing both positive and negative impacts of the project. at this matrix first activity cases, environmental factors have been identified and the severity (impact amplitude) and the importance (magnitude) of intended effects are considered. this matrix includes 100 small activities on the horizontal axis (columns) and 88 environmental factors on the vertical axis (rows) that results in the formation of 8800 houses matrix or tables which every home or cell is a merge level of activity from horizontal axis and a parameter from vertical axis. after listing sub activities and factors, when there is a possibility that one activity has an impact on environmental factor the diagonal line is drawn on soluble cell diameter as they cross over, then in each cell two numbers are considered that one of them is domain or impact intensity and other is importance or impact magnitude. impact importance criteria or domain are usually valuated by ±1 to ±5. at this method mark 5 very high and important positive impacts and mark 1 for a very low and insignificant partial effect is considered. also grade -5 for an excessive negative effect and grade -1 for a very low negative effect is considered. then these numbers sums and the sum of the numbers corresponding to each column represent the activity impact on all the assessed environmental factors. finally, for each environment (physical, economic, social, cultural and biological) and for each construction phase and operation of the various options, a number is obtained, which leads to the best option. assessing various impacts resulting from implementing the building of engineering constructions divided to construction phase and the phase of applying in physical, biological, socio-economic, and cultural environments in two cases of performing and failure to perform, in stages of preparing, constructing and applying, will be carried out. 4. results and discussion matrix generated in this study consists of 44 columns and includes factors related to the implementation and operation phases and 58 rows includes physical, biological, socio-economic and cultural factors. after the final evaluation matrix dam project for two options, performing and failure to perform will be carried out. at the option seeking studies in order to determine the location of bar dam and other proposed structures in this plan several options have been considered which finally options by authorities in terms of technical and economic will be reconsidered and only one option as a best will be chosen. therefore in bar dam environmental assessment only one option as a premier option is chosen. therefore, in bar dam environmental assessment and related constructions, only one option is considered so performing option or failure to implement the plan is reviewed. zero option or option failure to implement the plan means that if dam has not been constructing in the region and the area has been abandoned, causes which environmental impact? however, for evaluating the effects of this option we should not imagine that this option will not have any deleterious effects on the region, because in some cases the lack of an implementation plan can cause a non-rectification impact in the region. option a or option implements the plan at the current location in two constructions and operation phases is considered and the positive and negative effects of each phase have been determined. what is certain is that if implement or not implement the plan, there will be positive and negative impact on environment, but the important issue is making decision about implement or not to implement the plan. for making decision in this case, we should compare total impacts in two options of implement or failure to implement. in order to make the right decision on this issue the leopold matrix in order to evaluate dam's construction impact on environment is used. assessment of environmental impacts caused by dam projects in neyshabur, khorasan razavi separately construction phase and operation in the physical, biological, socio-economic and cultural environments in implementing option and failure to implement option was carried out. the impact separated result shows that the total number project impact in preparation and construction phase was 398 cases, which 117 cases means 30% positive and 281 cases means 70% was negative that the main reason was different physical operation in the regional environment which often are short and required. in the exploitation phase, 123 of cases of environmental consequences was 71, means 61% positive and 49 cases means 39% was negative. most of the adverse effects of the construction phase in implementing options are -263 which is related to physical environment and the greatest positive impact 729 is on the construction phase of implementing option on socio-economic environment. also negative effect in operation phase is 253 and positive effect is 473, while dam's impoundment and also considering measures related to the evaporation of water from the reservoir water level can bring desirable environmental impacts for the region and in case of water recourses reliable management cause positive impact on socio-economic development of the region. also results show that in exploitation phase more positive impact can be seen and this is more obvious particularly in socio-economic, cultural environment. economic environment with 729 positive points on construction phase and 384 positive points on exploitation phase has the highest positive impacts of implementing the plan. 5. conclusion generally based on the environmental assessment performed on the bar dam project and its affiliated structures, total value of the project are 1219 points positive and 1179 points negative. the dominant aspect of the project outcomes, especially in exploitation phase is positive and in situations which consequences are negative, mostly consequences have weak and negligible destructive load which in terms of quantity can be reduced by authentic management and implementing environmental proposed measures especially implementing sand stabilization and forestry side projects in dam's construction area which can reduce project negative intensity impacts. also, due to population growth and the increasing nutrient demands, unemployment and rural to urban migration, implementation has many positive results in employment status, income, migration, rural welfare and development of khorasan steel factory. so we can say that bar dam project implementation certainly has a lot of favorable impacts which trims adverse effects and creates large and significant benefits in the region. therefore, the project is economically valuable and in order to achieve favorable objectives and keeping pace and directing with macroeconomic policy, applying an appropriate environmental management system, set activities to give direction to form the possible negative effects resulting from the implementation of such a huge project to a minimum is required.