Commuters in Ottawa's east end got a small reprieve from traffic congestion as the city reopened one eastbound lane of Highway 174 Wednesday during the afternoon rush hour.

The highway has been closed since the afternoon of Sept. 4, when a large sinkhole formed in the eastbound lane near the Jeanne d'Arc Boulevard exit.

Workers continue to work around the clock to assemble a storm drain underneath the ground to replace one that failed last Tuesday and caused the sinkhole.

The lane opening was revealed in update provided Wednesday from Mayor Jim Watson, councillors and city staff.

Council also revealed the cost to fix the sinkhole is now projected at $4.9 million, not the $1.5 million that was first estimated.

With nine of the 18 storm drain pipes in place, the city has decided to open one eastbound lane from 3 p.m. to 8 p.m. at the Montreal Road exit during the week. The work on the sewer and the sinkhole is scheduled to be completed on Monday.

The city has added two new double-decker buses to help with express routes to and from the east end and more buses for Route 95. Some 360 new parking spots will be added at the Trim Road Park and Ride parking lot.

'Less sexy' projects a focus

The sinkhole has raised debate over not only the original work schedule on the storm drain, but also the funding for other local projects.

The mayor said Wednesday he requested an immediate inspection of similar city infrastructure located along critical roads as of Sept. 30. Also, Watson said he wants "an independent investigation to identify the root cause of the Highway 174 failure and to determine what, if anything, the city could have done differently," within 90 days.

An engineer also says old steel pipes, such as the one that caused the sinkhole, need to be replaced by concrete pipes.

Gerry Mulhern, who is also the executive director of the Ontario Concrete Pipe Association, has called for the public release of inspection reports of the Hwy. 174 culvert.