Page - 557 - in Book of Full Papers - Symposium Hydro Engineering

Water pollution refers to the contamination of a water source by some foreign substance that makes the water unsafe to drink or for use for agriculture and/or industry. This substance could be just about anything, and there are many factors causing water pollution. If the water source is changed in any way by the presence of that substance, then that water should be considered polluted [4]. While hydropower does not cause water or air pollution, it does have an environmental impact: Hydroelectric power plants may harm fish populations, change water temperature and flow (disturbing plants and animals) and force the relocation of people and animals who live near the dam site. Some fish, like salmon, may be prevented from swimming upstream to spawn. Technologies like fish ladders help salmon go up over dams and enter upstream spawning areas, but the presence of hydroelectric dams changes their migration patterns and hurts fish populations. Hydropower plants can also cause low dissolved oxygen levels in the water, which is harmful to river habitats. Reservoirs may also lead to the creation of methane, a harmful greenhouse gas [5]. In this research an environmentally friendly approach for dam construction and maintenance projects in Iran is proposed. The methodology takes into account diverse ranges of environmental issues and categorize them. Afterwards, proper remediation actions are developed to address each category. A brief review of related literature is stated in the next section, followed by Section 3 that presents the methodology development. Finally, Section 4 summarize some concluding remarks. 2. LITERATURE REVIEW Dams are used for a wide range of purposes including providing drinking water, agricultural water, industrial uses, flood control, and energy generation. The later one began in 1895 when the first dam and hydropower plant was built on the Niagara Falls successfully. The basic of hydropower does not have much changes in 120 years and since then, many efforts have been made to have a fresh look at hydropower to try to make it more environmentally friendly. That’s because, while hydro dams provides 85 percent of the world’s renewable electricity, it comes with a cost. Along with more commonly known issues such as habitat disruption, recent studies suggest reservoirs created by hydroelectric dams are a significant source of greenhouse gas emissions. That's why many environmentalists argue that other sustainable energy sources have evolved as better alternatives. For example, wind and solar have become cheaper in many countries and they are less risky in climate terms. They can be deployed more quickly, and they have smaller environmental and social footprints [6]. On the other hand, there are many experts believing that hydroelectric dams bring several benefits for societies such as job creation and flood control though it is of course necessary to mitigate their adverse impacts. For example, the US Department of Environment (DOE) develops new 557