Abstract: There is disclosed an apparatus for removing solids from water in a canal during or immediately after a rainstorm. The apparatus includes a plurality of filters and a carrier. The filters filter the solids from the water while moving in and taking impact from the water. The carrier carries the filters in a cycle.

Abstract: There is disclosed a device for removing small solids from water. The device includes an axle and a plurality of rotational filtering units installed on the axle. While rushed and hence rotated by water and small solids, the rotational filtering units filter the small solids. The device consumes little energy other than the water provides.

Abstract: An apparatus for detecting saturation of water in soil includes a housing including a lower section adapted for insertion in soil, a filter for permitting water into the housing while blocking soil, a sensor unit received in the housing for sending a signal when water level reaches a pre-determined position, and a control unit for receiving the signal from the sensor unit and for processing the signal.

Abstract: A water-monitoring apparatus includes a frame being installed by water. A reel is mounted on the frame. A tension cable is wound on the reel and including a lower end and an upper end. A buoy is connected with the tension cable. A control device is connected with the reel. When the water level changes, the control device rotates the reel so as to adjust a length of the tension cable extending from the reel for allowing the buoy to just float on the water surface. A detecting device is carried via the buoy for detecting at least one environmental characteristic and for producing at least one signal representative of the at least one environmental characteristic. A signal wire is electrically connected with the detecting device. The signal wire includes a helical section for automatically adjusting a distance between its two ends according to the position of the buoy. A monitor device is electrically connected with the signal wire.