Abstract: An excavation apparatus comprises a controlled flow underwater excavation apparatus. A housing thereof comprises at least one inlet and at least one outlet. The at least one inlet is provided on or at a side of the housing. A fluid flow path extends from the/each at least one inlet to the outlet. The fluid flow path comprises a first portion provided at or adjacent the/each at least one inlet. The first portion is included at a non-300 angle, e.g. is substantially perpendicular, to or converges towards a longitudinal axis of the housing and substantially straight. A second portion extends or continues from the first portion. A third portion extends or continues from the second portion. The third portion is substantially straight, contains at least part of a rotor, and is divergent away from the longitudinal axis of the housing in a flow direction from the inlet to the outlet.

Abstract: “There is disclosed an excavation apparatus (5), such as an underwater excavation apparatus, having means for producing, in use, at least one vortex, spiral or turbulent flow in a laminar flow of fluid, e.g. water. The excavation apparatus (5) comprises a rotor (10) having a rotor rotation axis (A), wherein, in use, flow of fluid past or across the rotor (10) is at a first angle (?) from the axis of rotation (A). The excavation apparatus (5) comprises the rotor (5) and means or an arrangement for dampening reactive torque on the apparatus (5) caused by rotation of the rotor (10), in use. The turbulent flow is provided within, such as within a (transverse) cross-section, of the laminar flow.

Abstract: An apparatus for treating contaminated water and may include an inlet, configured to receive contaminated water from a body of water. The contaminated water may include one or more pollutants (such as oil), and the apparatus may be configured to provide for separating those pollutant(s) from water to provide recovered pollutant(s) (e.g. recovered oil) and treated water. The apparatus may also include a water outlet for returning treated water to a body of water. In some examples, the apparatus comprises a separation volume, having inner and outer chamber, which can be used to separate rotating contaminated water.