The cascade of hydropower plants is located by the spa town of Sandanski at the foot of the Pirin Mountains in the southeast of Bulgaria. The cascade consists of three high-pressure hydropower plants with accumulative function with a total installed capacity of 56.40 MW. A natural waterfall is situated in the vicinity of the Popina Laka Hydropower Plant.
The hydropower plants process mountain water. There is a large number of headwater channels and reservoirs, which enable daily water accumulation and operation in a peak load regime. The cascade was built between 1969 – 1971, and was acquired by ENERGO-PRO in 2002. In the years 2004 – 2006, the cascade underwent complete reconstruction, which was carried out with the participation of Czech companies.