Dredging drain for water tank - use network of drain pipes in pool floor with successively actuated valves giving localised draw down

摘要

The system effects the semi-automatic dredging of a locked yachting basin using a network of pipes built into the basin floor. The network may comprise a main pipe with perpendicular laterals, the former discharging into a drainage ditch on the sea side of the basin wall and the latter branching to accommodate dredging points. Valves with anti-clogging filters control each lateral being opened and closed in sequence to obtain a draw-down dredging effect. The pipes may be constructed in reinforced concrete, and a brushing barge may be used to loosen sediment.