TTC CEO Andy Byford has issued a letter to members of the Commission and to Council advising that a planned shutdown of the subway for major reconstruction in the vicinity of Davisville Station has been put off until 2016. In the meantime, sufficient repairs will be done to keep trains moving at a reasonable speed through this section.
The underlying problem, quite literally, is that the foundation and drainage below the track have failed causing the track to be unstable. The condition has been addressed off-and-on for a few years with slow orders, but this does not solve the problem.
This and other areas of the subway system with wood tie/stone ballast track will be 60 years old in 2014. This is well past the normal operating life for such systems.
Detailed investigations have determined that in addition to normal wear and tear, the area below the stone ballast and the associated subgrade drainage systems have both failed, allowing enough movement of the track system to cause abnormal track movement which, in turn, can cause the signal system to fail safe. Subway service in the area is safe, but reliability on our busiest line is not where it needs to be.
The TTC will have to dig down substantially below track level, and this is the sort of maintenance that cannot be carried out overnight of on a weekend. The number of buses and operators needed to bridge this section of the line is well into the hundreds, and the TTC does not have these resources. Short shutdowns may be attempted and these will be co-ordinated with other work in the same section of the route.
If ever there were a need to demonstrate that subways do not last 100 years, as some short-sighted advocates claim, this is a perfect example. The Yonge line is now 60 years old and parts of it are showing their age. Indeed, another section at Lawrence Station also requires major repairs even though it is barely 40 years old.
Read the full memo.