5. Pournari dam

The Pournari dam was constructed in 1973-1976 as part of a wider effort by the Greek government to take advantage of the country’s water resources. It is the second-largest dam in Greece: its width at the top is ten meters but it widens to 450 meters at the base to be able to withstand the pressure from the 865 million cubic meters of water in the reservoir. During the dam’s construction, the Arachthos river was diverted to a 700-meter long tunnel excavated in the mountain-side next to the future artificial lake. The tunnel was sealed on 10 January 1981 and the reservoir began to fill with water.

The reservoir behind the dam had a profound effect on the region’s ecology. Many species of fish and aquatic birds thrive in its waters, but the construction of the dam restricted the flow of water and lowered the water table in the plain of Arta. There was simply not enough water flowing in the river to infiltrate the soil and replenish the groundwater supplies. The problem was partially solved with the construction of a second lower dam (Pournari II) at the base of the main dam (Pournari I) to ensure a year-long flow of water in the river. Unfortunately the approach to the main dam is restricted and there is no easy road access to the shores of the lake.