Epcor drainage project on 105 Street finishes more than a year late

Work delayed after underground borer was trapped once and broke down twice

An Epcor drainage project that snarled traffic on 105 Street south of Jasper Avenue for months was finished Thursday, more than a year behind schedule.

Work began in November 2017 and was initially expected to be completed by last May.

The project involved drilling an underground 1,500 millimetre storm tunnel north under 105 Street to a point beside Beaver Hills House Park, to upgrade the stormwater system after an explosion of condos and office buildings in the area. It was part of the Downtown Intensification Storm Tunnel project.

Traffic disruptions included reducing parts of 105 Street south of Jasper to a single lane, partially eliminating street parking and restricting left turns.

In March last year, the project was delayed by an anticipated seven months after the borer struck “tougher clay” than expected.

An access shaft had to be drilled 24 metres below ground to reach the trapped borer, which then had to be serviced and its hydraulics upgraded to allow it to bore through the tough clay.

Then, in August 2018, the boring machine was damaged by underground metal material, which required it to be repaired in proximity to the LRT.

“This proximity of the repair location to the LRT presented additional risk, which required engineering considerations to ensure the safety and protection of the underground infrastructure,” said Kelly Struski, spokeswoman for Epcor in an email Thursday.

In May of this year, the boring machine broke for a second time when it again encountered metal material. It damaged the machine and stopped tunnelling temporarily under 105 Street, with approximately 15 metres of tunnelling left to complete.

The hand tunnelling of the final 15 metres and pipe installation have been completed.

Struski said the next step is to fully connect the tunnel to the drainage system and then work on the chamber inside the shaft to prepare for the manhole installation to begin.

Lane closures will continue to be in place on 105 Street north of Jasper Avenue until work is complete, however, no additional traffic impacts are expected.

That work is scheduled to be completed by the end of September.