In the fall of 2015, we completed the massive Interior to Lower Mainland Project (ILM) on time and on budget. The transmission line crosses 150 miles of rugged terrain that includes four mountain ranges, much of which is covered in snow pack for up to ten months of the year.
The new, 4 bundle 500 kV line parallels an existing line allowing the use of some existing right of ways. But, this also creates the potential for a high induction corridor and its inherent difficulties with electrical grounding.
The expansion of that line’s power capacity did bring very needed electricity from Merritt in the B.C. interior, near where it is generated, to the three million people in Vancouver, Canada and the Lower Mainland area.
We erected 590 steel lattice towers, weighing more than 20,000 tons, in 17 different configurations designed to deal with extremely challenging locations. Cable was strung at elevations up to 6000 feet and heavy lift helicopters were used greatly.
We pride ourselves on the use of helicopter hoist techniques (Sky Transfer) that limited the time period where workers were at risk under the helicopter. The Sikorsky S64F was used for flying steel while 14 other helicopters were used for conductor sagging, dead-ending, clipping, spacing and cable stringing.
For our crews the ILM Project was particularly challenging, with extensive climbing and helicopter flying at high altitudes. All our safety practices were strictly adhered to and as always, our company and our employees demonstrated an uncompromising regard for the environment and local communities.
- Multiple Elevation Changes to 6000', traversing four mountain ranges.
- Areas with snow pack for ten months per year.
- Three river crossings greater than 0.5 miles in length.
- Parallel to existing 500 kV Lines – High Induction corridor.
- 35% of the project was completed by use of a helicopter.