Construction is underway on the Trans Mountain Expansion Project which means additional activity at our facilities and along our right-of-way. We aim to minimize disruption to our neighbours during construction and have developed plans to reduce impacts, including those from noise, light, dust and traffic disruptions.

Trans Mountain has completed studies to better understand the impacts of construction related activities. Those studies, along with feedback from local residents, have led to planned mitigation measures to help reduce the impact of our work.

One of the impacts our neighbours may experience during construction is vibration. Vibration can be experienced as shaking of structures or physical sensations. It can be caused by either the airborne component of sound – low frequency noise (LFN) – or by ground-borne vibration.

There are various stages of pipeline construction that have the potential to generate vibration, including clearing and grading the right-of-way, digging trenches, stringing and lowering pipe into the trench, backfilling and final reclamation. This vibration will be temporary in nature and levels will depend on the type of work being done.

For the Project, measurements were conducted at several locations to capture typical noise and vibration levels during construction along the right-of-way. Specific measurements were also conducted for noise caused by major equipment on site.

Vibration is often present in our surroundings, but when vibration levels are elevated they can become “felt” or “noticeable”.

LOW FREQUENCY NOISE (LFN)

LFN has the potential to cause perceptible rattling in light fixtures, doors, windows, etc. Our assessment found that residences adjacent to or near our right-of-way construction will most likely experience some perceptible vibrations associated with LFN.

Although LFN from our construction activities could result in the movement of objects, such as a picture hung on the wall becoming crooked, the noise levels measured are not significant enough to cause structural damage.

By managing noise, the related vibration can also be managed. To this end, Trans Mountain has developed noise management plans to manage construction noise. A number of mitigations outlined in our plans are effective in also limiting this type of vibration.

GROUND-BORNE VIBRATION

Our assessment found that residences adjacent or near our right-of-way construction will most likely experience some perceptible ground-borne vibrations, however the predicted levels are not significant enough to cause any structural damage.

As we move forward with construction, our plans will be refined based on additional data collected and feedback received from neighbours.