of the water level and the flooding of previously dry areas, which produced chemical changes in the water, including a drop in water oxygen levels. Besides, the alteration of the streams of water affected the dynamics of the floating vegetation that in the system Iberá is the habitat of many endemic species. The more calm water behind the dam has also allowed the spread of waterborne diseases and disease vectors, such as schistosomiasis, dengue fever and malaria. The structure and composition of the productive activities of the primary sector, that in addition to the direct flooding also modifies the level of humidity of thousand of hectares destined to agriculture and the exploit of wood, thousands of cattle were lost in the process of formation of the lake. Destruction of the habitat submerged by the dam could cause great loss of biodiversity. Numerous protected species have been affected in one of the few spaces in which they survive in Paraguay and Argentina, including pampas deer, capybara, certain water birds and yacare caiman. The consequences for the fish population of Paraná have been very severe, causing a large drop in the volume of some species, especially when the dam was first constructed. Aquatic invertebrates also declined. For example, among four Aylacostoma aquatic snails restricted to the area, two became extinct, one extinct in the wild, and the final is seriously threatened. The construction of the system of elevators helped reduce this effect . Current state Before February 2011, the water level was above sea level, less than planned. This caused the hydroelectric component of the dam to operate at only 60% of its capacity. The water level was raised, bringing it to above sea level and covering another of land surface, affecting more than 50,000 people. This brought the installed capacity to its final design of 3,100 MW and the annual generation to about 20,000 GWh. The plan to finish the Yacyretá project included: Freeing the flooded areas, taking into consideration the expropriation of properties, the safety of the freed areas, the relocation of the population and the rehabilitation of the economy. Doing all the necessary work to reduce negative effects on the natural environment. Repairing the infrastructure, routes, bridges, ports, airports, electric supply lines, etc. Repairing the damage to the urban areas of Encarnación, Posadas and other cities. Problems with transmission lines for the Yacyretá Dam caused, it has been claimed,