UNDER KEEL CLEARANCE MARTÍN GARCÍA CHANNELS Vessels sailing along Martín García Channels are required to ensure at all times 0,60 metres (2 feet) of under keel clearance (UKC). For further information, see the publication of Martín García Channels Regulations (REMAGA), chapter II, section 2.9, published by the Administrative Commission for the Río de la Plata, CARP.