WATER QUALITY IMPROVEMENT DEVICE FOR CLOSED WATER AREA BY FENCE

PROBLEM TO BE SOLVED: To provide a device which is capable of avoiding the lower part of a fence for the improvement of water quality from reaching the bottom of a lake even when the water level of a closed water area, such as a dam reservoir drops. SOLUTION: A water quality improvement device is provided with a float 10 floating in the transverse direction in a dam reservoir where a fence 11 is provided in the reservoir hangingly from the float 10. The fence 11 separates the upper layer portion of the reservoir into the upstream side and the downstream side, thereby improving the water quality of the reservoir. In the water quality improvement device described above, there are provided a water level meter 15 which detects the water level of the reservoir, a relay device 16 which computes and processes the detection data transmitted from the water level meter 15 and thereby outputs a control signal and a drive device 14 which incorporates the control signal and moves vertically the fence 11. This construction makes it possible to move the fence 11 upward when the water level of the reservoir drops and moves downward in automatic mode when the water level of the reservoir rises.