NEW head gates were finally lifted into place at Grafton Lock on Wednesday, after flooding delayed the replacement of the structures.
The Environment Agency aimed to have all of the work completed before the boating season starts on the River Thames next month, but will now wait until the season is over in November to replace the tail gates.
Water was pumped out and fish were rescued in early January when the gates were first removed, but soon afterwards, long bouts of heavy rainfall and severe flooding caused work to come to a halt.
Throughout the rest of March the Environment Agency will be clearing the West Oxfordshire site, beween Kelmscott and Radcot, and draining it again.
Operations leader Al Wells said: “We were forced to stop work on the site due to the exceptional rainfall.
“Water levels are now falling and work has restarted.
“Given that the boating season is only a month away, we have decided to replace the head gates and then demobilise the site.
“The tail gates will be stored until November, when they will be replaced during the next closure.”
The timber gates being replaced were first installed in 1970 and the ones set for a change in November in were put in during 1989.
Both sets were in poor condition, said the Environment Agency, and needed to be replaced.
The tropical hardwood replacements were constructed by carpenters in Oxford at the agency's Osney Yard in September and October of last year.
The work is part of a £3m scheme to refurbish locks and weirs across Oxfordshire.
The work has been funded through a combination of boat registration charges and navigation-related commercial activity, such as mooring fees with a top-up of Government funding.
Other locks which have undertaken work include Iffley lock, Osney lock, Abingdon lock and Culham lock.