Bearing device for hydraulic machine and hydraulic machine

The invention relates to a bearing device for a hydraulic machine and the hydraulic machine, which can restrain increase of manufacturing cost and restrain abrasion of a main bearing caused by impurities contained in river water. A bearing device for a hydraulic machine is provided with: a main bearing provided on the outer periphery of a main shaft and supporting the main shaft; an upper water tank for accommodating the main bearing and lubricating water for impregnating the main bearing; a lower water tank which is provided closer to the runner than the upper water tank, and into which a part of the river water that rotationally drives the runner flows; and a main shaft water sealing part which is arranged between the lower water tank and the runner, forms a gap for the flow of the river water between the main shaft water sealing part and the periphery of the main shaft, and reduces the flow rate of the river water flowing into the lower water tank. The lower water tank separates impurities from the river w