Tunneling on the Ottawa LRT project have resumed following a sinkhole that halted construction on June 8. The sinkhole spanned three lanes of traffic and broken water mains caused flooding in the tunnel.
Utility and street repairs have been completed and the sinkhole filled with concrete. Rideau Transit Group (RTG) has approximately 50 m left to complete the tunnel.
According to Steve Cripps, Director of the city’s Rail Implementation Office, Ottawa and RTG personnel will on-site, above ground and in the tunnel, to monitor construction activities. Additionally, SEM mining will be conducted in small segments in an effort to mitigate risks. Additional supports (pipe roofing, lattice girders, face bolts, etc.) will be used in conjunction with grouting to help improve the ground. Monitoring of the ground and adjacent buildings is ongoing, while monitoring of water mains has been increased.
The Confederation Line is $2.1 billion project that includes 12.5 km of rail between Blair Station in the east and Tunney’s Pasture in the west. The route includes 13 stations and a 2.5-km tunnel that will alleviate congestion through the downtown core.