Collaboration of local government units in the Skrapež river watershed for soil erosion control and active flood defense

Collaboration among local self-government units within the Skrapež River basin (municipalities of Čačak, Sevojno, Valjevo, Užice, Bajina Bašta, Požega, Gornji Milanovac, and Kosjerić) represents a crucial factor in controlling soil erosion and actively defending against floods in the area. The Skrapež River basin, characterized by a fan-shaped and symmetrical form, is situated within the microregion of Srpska Crna Gora within the Western Morava region. It features a specific topography ranging from a minimum elevation of 305 m to a maximum elevation of 1347 m. Hilly-mountainous terrain occupies 46.63% of the surveyed area, with an average river basin slope of 18.36 m/km. Most of the basin is covered by metamorphic rocks (206.52 km²). The climatic parameters of the basin, with an average annual temperature of 9.55 °C and precipitation of 644.16 mm, influence erosion processes and hydrological characteristics of the basin. Using the Gavrilović method, the average yearly sediment yield was calculated at 249,650.24 m³/year, with the identification of 127 erosive channels. Maximum flows occur in May and June, with the most significant variations in the basin observed in September, May, and August. To prevent the destructive effects of major floods, it is necessary to establish collaboration and coordination among the mentioned local self-government units to prevent stream siltation, implement preventive anti-erosion measures, and carry out biotechnical protective works.