The CTA wants GO to use quieter pile-driving technology and limit work to 40 hours a week between 8 a.m. and 4 p.m. It also recommends GO create a website updating residents about the noise and vibration.

The transportation agency acknowledges that GO must rebuild the diamond to expand transit services in the Greater Toronto Area, but it must also balance that need against the rights of the community.

GO has already implemented many of the recommendations, but using quieter techniques mean the project — which it would have finished by the end of this year — will continue until next summer. The construction, which involves driving watertight steel caissons into the ground, is part of GO’s project to build a bridge to separate GO commuter trains operating along GO’s 31 Georgetown line from Canadian Pacific Railway freight trains.

The $277-million project will reduce the travel time for commuters by lowering the Canadian National Railways’ Weston Subdivision tracks to run below CP’s North Toronto line, rather than across it. This eliminates scheduling conflicts between CP freight trains and GO trains, increasing the frequency of GO service to Brampton and Georgetown. The project is a major component of GO and Metrolinx project to expand the Georgetown South corridor.

The West Toronto Diamond Community Group complained to the CTA about the noise and vibration resulting from GO’s project. The City of Toronto supported the residents.

The CTA found that exposing local residents to the noise and vibration resulting from piledriving is unreasonable, since some of the nearby area is residential and that GO had failed to set up adequate measures to reduce the effects.

It proposed that GO use a number of different techniques for driving the piles and to muffle the effect on the neighbourhood. It ordered GO to negotiate with the City to close down nearby streets and with other railways to block trains from the area while work is going on. (The City closed Old Weston Road south of Davenport Road on October 22.) It also requires GO to monitor noise and vibration levels, develop a website to communicate better with residents about current construction activities and the equipment it will use.

GO must also provide at least two weeks’ notice of any change to the project plans, including the schedule for pile-driving activities and any projected periods of inactivity, an e-mail address and telephone line for residents to communicate particular concerns about the current and projected pile-driving activities.

The agency ordered GO to investigate and respond within 48 hours to any inquiries about the project. It must also post on its website a weekly report containing noise and vibration measurements and assessing the effectiveness of measures it has set up to reduce noise and vibration, details of any complaints it has received and how it has resolved the complaints.