Meeting Date: March 26, 2008
 
Subject:  Nightly Early Closure Of Portions Of North Yonge Subway To Accommodate Tunnel Liner Repairs
 
Action Item: X  

Recommendation

It is recommended that the Commission approve the 12:30 a.m. shutdown of revenue service on portions of the North Yonge Subway, Sunday through Friday, for 25 months commencing June 2008 board period, to accommodate the rehabilitation of structural pre-cast concrete tunnel liners, as identified for repair by the third party consultant. 

Discussion

Working within the current maintenance window, after revenue subway service has ended, repair crews have been unable to maintain a production rate that will meet the revised completion date of July 31, 2010. At the current rate of production, the estimated completion date for this project is January 1, 2013.  This is undesirable.  As the current rate of deterioration of the structural tunnel liners is uncertain, a scheduled completion date beyond July 31, 2010 may necessitate a complete closure of the North Yonge Subway north of Eglinton Station should the condition of the structural tunnel liners worsen.  
 
If approved, a staged early shutdown of portions of the North Yonge Subway over the next 25 months would enable crews to bring the project back on schedule for a July 31, 2010 completion date.
 
Repair work would be concentrated on the tunnel liners between York Mills to Sheppard for the first eight months.  The remaining liners will be completed in the following 17 months in the areas between Eglinton and Lawrence Stations and between Lawrence to York Mills Stations. 
 
The requested early closures would be scheduled as follows; 

  • Lawrence Station to Finch Station -  June 2008 to February 2009
  • Davisville Station to Sheppard/Yonge Station - March 2009 to July 2010  

During the periods of closure, a bus shuttle will be implemented over the affected areas for customer accommodation. 
 
This work may impact production on other unrelated capital rehabilitation projects in this area. Track & Structure staff will monitor the production on these unrelated projects and make every effort to maintain established schedules.
 
A presentation will be made regarding this request. 
 
February 27, 2008
6-261
Attachment