The aim of the study is to develop a methodology for the hydraulic calculation of a spawning or spawning-fish canal with a differently fractured gravel-pebble bed covering. Spawning and fish-spawning canals are recommended to be arranged with low-pressure river and ravine-girder water units. An obligatory condition for such channels arrangement is their channels covering with a spawning substrate, that is a gravel-pebble mixture for lithophilic fish species. When applying this type of coating the usage of various components of gravel and pebble mixtures laid on channel slopes and bottom is envisaged. The proposed methodology of hydraulic calculation is based on the scientific-analytical approach and provides for compli-ance with the requirements for geometry and hydraulics of channels, determined by the type of anadromous migrating fish. The size variation of the applied gravel-pebble mixture and consequently different hydraulic resistance to the flow along the canal bottom and slopes is suggested to be taken into account by means of a given roughness coefficient determined by corresponding experimental dependences by the developed technique. The calculation proce-dure has been worked out to the level of the program for electronic computers in the pro-gramming environment “MathCAD” and proved with the hydraulic calculation of the Shap-sug fish spawning channel at a flow rate of 4 cub m per sec with an average flow velocity of 0.7 m per sec and the depth of filling the channel part of the canal 1.0 m. The conditions nec-essary for spawning vimbas and shemayas in this canal are provided with a channel width along the bottom – 4.5 m, slopes laying – 1:1.5, slope of its bottom – 0,00091 and by covering the canal slopes with a gravel-pebble diameter 20–40 mm and the bottom – 120–150 mm.
Key words: fish reclamation, fisheries, fish spawning, fish canal, spawning canal, channel hydraulics, channel roughness, substrate.
