We measured 79 transversal water obstacles with potential impact on the upstream passage of fish in Baca river. There were 13 hydropower plants among them and only 1 fish-pass, which were assessed as non-passable for all target fish species. We also included the state of the obstacles in the field survey, determining most of them as partially damaged (with a damage range between 10-30 %). For the assessment of fish passability, we used indirect scoring and classification ICE method (protocol), based on a comparison of the typological, geometric and hydraulic characterisrics with the swimming and jumping capabilities of the fish species analysed. All objects were ranged in groups regarding the ICE protocol. We assessed the passability using the multi-stage criterion based on comparison of measured and calculated threshold characteristic value, and classify objects into one of 5 passability classes: 0; 0,33; 0,66; 1, NC. The group with the highest passability assessment was ROCK group. According to the results measured at low water levels, the passability of rheophilic cyprinids was 24 %. The lowest passability was assessed for Bullhead (14 %). Passability of grayling (59 %) and the Adriatic grayling (51 %) was higher in comparison with rheophilic cyprinids and lower compared to the biggest representative of Salmo family. The highest passability had alien rainbow trout (65 %). We have confirmed that the longitudinal connectivity of Bača river is interrupted along the entire watercourse, which is also shown by the fact that there are 3 obstacles built on average every kilometre.