Customer: Veletekstil d.o.o.
Location: Zaboršt, Municipality of Dol pri Ljubljani, Slovenia
Project: Project of operating permit
Completion date: 2013

The project deals with the stream regulation in the village Zaboršt, Dol near Ljubljana. The main downstream is in urban area and from water framework directive perspective was completely unregulated and as such represented a life and economic threat to all local residents and facilities. The physical view of the terrain and the community reports and the above-mentioned facts show that the watercourse is not just a usual stream but dangerous and heavy torrential water. In this case it was necessary to prepare the complex hydrological analysis of the area, since there is no meteorological station in this area. The missed data was available by the surrounding stations, information from the general characteristic rainfall and from the date and
time occurrence of catastrophic floods in July 2009. The lack of and uncertainty of the input data was supplemented by remote stations and a specific weights method. With the consultation from the Slovenian Environment Agency the actual view of the terrain and visual assessment of the hydrological situation was made. With so calculated hydrographs and runoff simulations of flood waves the water channel was designed to extreme conditions. The channel is now regulated to provide flood protection facilities on the banks of the watercourse. Project demanded reduction of riverbed level, inclination reduction, which is ensured by intermediate rectangular weirs. The cross-section of the channel is designed as most beneficial hydraulic trapezoidal shape, which conduct the projected 100-year flood water. Riverbed and bank treatment are ripraped in such matter to provide erosion protection. Flood area was also considered and designed for the occurrence of extreme torrential conditions. Rate of sediment alluvial suspension and debris transport was also considered to prevent unwanted tipping gravel in the riverbed or even before the road culvert. Natural fish pools and fish ways with inclined river bank barbs were included to ensure the needs for natural fisheries regulations.