The lake Slivniško jezero was made in 1976 when the barrier Tratna was built. The fishing family Voglajna has started managing the fishlife in the following year. Many different fish species were put in the lake: grass carp, silver bream, gibel carp, asp, ide, chub, crucian carp, carp, tench, perch, common bream, common nase, common roach, common rudd, zander, catfish, pike, silver carp and bleak. They all adapted pretty well due to the plenty of food the reed offers. In November 2013 the largest freshwater fish in Slovenia has been caught here. it was a catfish, 255 cm long and 95kg heavy.
|The creek Kozarica (from Ravne to the outflow into the Voglajna)|
|The creek Pešnica (from the confluence with the creek Jesenek to the outflow into the Voglajna)|
|The creek Slomski potok (from the confluence with the creek Zagrajski potok to the outflow into the Voglajna)|
|The river Voglajna (from the bridge Tratna to the outflow into the Savinja)|
|The Voglajna's backwaters (from Prožniška vas to the outflow into the Voglajna)|