FIELD: hydroelectric power engineering; construction of small river-arm power plants. SUBSTANCE: river-arm channel is dammed by means of temporary cofferdam on upstream and downstream sections without damming main river channel. Canal with deepened bottom on its upstream section up to bottom levels at point of arm entrance to river channel is built in river arm downstream of cofferdams. Powerhouse accommodating hydropower units is constructed downstream of cofferdam in upstream section and joined through dikes with river arm banks. EFFECT: reduced capital outlays, minimized detrimental impact on environment. 2 cl, 3 dwg
