The Challenge
Trimet needed noise and vibration consulting services for the South/North Transit Corridor Study DEIS. The Light Rail line was proposed to run approximately eighteen miles from Clackamas, Oregon through the Portland Central Business District and ending in Vancouver, Washington.
The Strategy
HMMH services on this project included:
- Ground-borne vibration propagation testing
- Noise and vibration tests of the Trimet LRT vehicle
- Noise and vibration predictions and assessment
- Design of mitigation measures
- Preparation of the noise and vibration sections of the DEIS
The noise and vibration impacts were carefully evaluated to minimize the costs of mitigation measures.


