(New throughout, adds details, comments from shipping agent)
SAO PAULO, Sept 28 (Reuters) - Brazil's Santos port authority has decided to reduce the drafts on some terminals, including ones operated by a subsidiary of Asian commodities trader Noble Group and sugar trader Copersucar, due to excess sediment, two shipping agencies said on Monday.
The reductions vary from 0.3 to 2 meters, possibly reducing ship loading capacity at the terminals, the agencies said.
Shipping Agency Williams said in a note to clients that local port authority Codesp in Santos, Latin America's largest port, had confirmed new drafts at Barnabe Island's terminal, Noble Agri's terminal and Copersucar's terminal.
Santos' Codesp was not immediately available for comment.
A second shipping agency, who asked not to be named, also confirmed the reductions.
"Small changes always happen, but this time it took us by surprise. Noble suffered a sharp reduction," said an agent at the second shipping company.
According to the note from Williams, the maximum allowed draft now on the Noble terminal is 10.10 meters at low tide, from 12.10 meters previously.
At Copersucar berths, allowed draft fell to 11.70 at low tide, compared to 12.50 meters before.
"This will impact loadings for sure," said the agent, estimating a reduction of 800 tonnes of capacity for each 0.10 meter reduction on the draft.
The reductions are likely to increase operation costs for the affected terminals.
Brazil is in the peak period for sugar exports and is also shipping large amounts of its second corn crop.
Line-up data shows that four ships with corn and seven with sugar should leave Copersucar's terminal in the coming days.
At Noble's terminal, the line-up shows movement of eight ships carrying corn and soymeal.
The Barnabé Island terminal moves mainly fuels.
Noble and Copersucar did not reply to requests for comment. (Reporting by Gustavo Bonato; Writing by Marcelo Teixeira; Editing by David Gregorio)