The Panama Canal Authority (PCA) proposes a temporary half-foot reduction in maximum draughts of ships passing through the canal due to the “El Nino” effect and would be effective from September 8, 2015.
PCA has announced the cut down on the maximum draughts of ships passing through the canal and plans to have an additional reduction if rainfall stays below normal levels. The maximum permitted transit draught for the Panama Canal is 11.89 metres (39 feet) Tropical Fresh Water (TFW) and would be effective from September 8, 2015. The details are as follows:
- Ships loaded prior to 11 August 2015 to a draught in excess of 11.89 metres (39 feet) will be allowed to transit and are subjected to safety considerations.
- Ships loaded on or after 11 August 2015 must comply with the restrictions and may be required to trim or off-load cargo.
The water density of the Gatun Lake is 0.9954 at 29.4°C (85°F) and the maximum permitted transit draught is the deepest point of immersion in TFW permitted for a particular vessel in the Gatun Lake. There can be further restrictions in maximum allowed transit draught up to 11.73 metres (38.5 feet) TFW on 15 September 2015 and conditions applicable would be as follows:
- The 11.73 metre (38.5 feet) restriction will be implemented, if ships loaded prior to 18, August 2015 will be allowed to transit, subject to safety considerations.
- Ships loaded on or after 18 August 2015 must comply with the restrictions and may be required to trim or off-load cargo.
These draught restrictions are for the planning purposes only and its final number depends upon the actual rainfall and the lake’s water levels. These draught restrictions are imposed on every 15-centimetre increments at a time. These changes are announced at least five weeks in advance to allow vessels to comply with the restriction.
El Nino refers to the ocean-atmosphere complex weather phenomenon consisting of a cycle of warm and cold temperatures patterns resulting from variations in ocean temperatures in the Equatorial Pacific. In the Panama Canal, this phenomenon is characterised by the reduction in rainfall in the Canal watershed, which causes a fall in the water levels below the average of Gatun and Madden lakes.
Source: Gard
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