Honda’s Thailand assembly plant in Ayutthaya, which was submerged when floodwaters inundated the factory on October 9, may be out of action for up to six months, according to reports.

The automaker will need to replace a range of equipment damaged by the flood, and is still attempting to determine the full extent of the damage at its factory in the Rojana Industrial Park, where it produces its Civic and City models – the area remains submerged under two to three metres of water, and most of the flood-hit equipment remains inaccessible. The floodwaters are expected to recede in mid-November at the earliest.

The firm’s suppliers in Thailand have also been affected by the extensive flooding, as roads and other key infrastructure have been severely disrupted. “We will be forced to revamp the plant,” one Honda official was quoted as saying.

The reports add that the automaker has apparently told some of its suppliers that it will probably take six months before it can resume operations at the facility, and will likely not reopen the plant until next spring.

The company’s total production loss is expected to exceed 100,000 units, accounting for about 3% of the automaker’s planned global output for fiscal 2011. While Japan’s eight automakers have operations in the Southeast Asian nation, Honda is the only manufacturer whose facilities have been directly damaged by the floods. Honda Malaysia had last week announced a temporary halt to its production in Melaka as a result of parts shortages caused by the Thai floods.

In related news, Toyota has begun cutting output in seven countries – Japan, the US, Canada, South Africa, Indonesia, Vietnam and the Philippines – from today until November 5 as a result of the flooding in Thailand. While its facilities in the Kingdom have not been directly hit by the floods, operation at its three factories in the country have been halted since October 10, and potential delays in the procurement of parts are expected.

Elsewhere, Mazda halted production at its AutoAlliance JV plant with Ford in Rayong from Wednesday to Friday last week, as parts shortages came into play. The company said it was considering shipping parts to the facility from China and Japan.