MONTREAL - Months after one span of the Mercier Bridge was abruptly closed for emergency repairs, Quebec's Ministry of Transportation finally revealed several reports into the safety of the structure.

This summer CTV News requested those reports under the Access to Information act, but our request was denied.

The Mercier Bridge is actually two structures, one built in the 1930s, with the second, inbound span built in the 1960s, and it was the older span that was suddenly closed on June 14, 2011.

That was when Transportation officials said that about 10 gusset plates, which secure the bottom of beams arranged in an interlocking X-shaped pattern, were severely eroded.

However the inspection report that detected the rust was completed in December 2010, and officials did not say why it took six months for them to act.

They did proclaim that the bridge was structurally sound and not in danger of collapse when it was closed in June.

A 2008 inspection revealed that 347 out of 4,000 pieces of the bridge were in critical condition. 

Repair work on that damage was completed in 2010, but it was only because officials then considered strengthening the guardrails that they found damage that did not exist three years earlier.

In essence, the bridge deteriorated much faster than anticipated.

The outbound side of the Mercier Bridge was reopened on Sept. 6, 2011, although only one of the two lanes is open to traffic.