Abstract: An underwater vacuum including a housing having an opening which is positioned adjacent the surface to be cleaned. The housing also supports a rotatable brush powered by a turbine energized by water flow through the vacuum. The housing has a water outlet which communicates with a pump at the surface of the water. The inlet to the turbine has a trap which collects large debris that could damage the turbine blades. The vacuum has two rear wheels that are adjustably attached to the interior of the housing, and two front wheels that are adjustably attached to the exterior of the housing. The underwater vacuum can remove sediment from a water storage reservoir without causing turbidity in the water column. A second handheld embodiment is used for cleaning sloping berms, and has rear wheels that are also powered by the turbine.