To the editor:
I now feel very comfortable again about the construction of our new Pickering Middle School, and I want to pass the word to my neighbors so they’ll now know the facts and hopefully feel comfortable too.
Last Wednesday I was sure to make time to attend the new Pickering Middle School Public Forum in the current Pickering gym. The assembled panel consisted of senior leadership of the school department, the mayor, senior leadership of the project management team, the architect, the project engineer and the project construction superintendent.
I attended the forum not only to stay informed about such a huge neighborhood/school project (the City Council had just approved, the night before, an additional $9M bond on top of the base cost of $175M), but I needed to know the facts about the initial foundation issue that caused some cracking in the existing Sisson School walls months ago, and what they are doing about it.
The big question in my mind, and I know in many other’s minds, was “is this building going to sink” like one of new high schools did? What better forum to ask these questions than this.
I waited patiently for my turn, approached the microphone and asked the following questions:
1) What was the original method used for the foundation base, and why did it cause interaction with the Sisson building?
2) What is the re-design and what new methods are being used now?
3) Are you pinning to bedrock, and if not, how are the new methods equivalent or better?
All my questions were answered satisfactorily. Basically, the original method induced some vibration that affected the Sisson building. Some hairline cracks, but nothing was sinking. I think they stopped immediately, and a re-design and search for new methods started after the root cause was found.
They described in the forum that two new methods were employed – rigid inclusions and earthquake drains. The quantity, locations and depths of these rigid inclusions and earthquake drains all account for the adequate foundation base needed, equivalent to pinning to bedrock. Pinning to bedrock was said to be cost-prohibitive because of it’s excessive depth, even on the hill in the old Sisson school yard.
What made me feel fully comfortable was the fact that engineering peer reviews took place. Outside engineering companies were hired to thoroughly review all aspects of the redesigns of the foundation base and the exact soil conditions and layering of the site. I believe there was more than one engineering firm brought into to double check everything before work proceeded again. This is what I was looking for.
I was also fortunate enough to quickly tour the construction site after the forum. There I saw blue-toothed vibration monitors attached to the Sisson building. I also saw attached to Sisson, all along it’s end walls, three types of laser reflectors. A central construction site laser near Magnolia Ave laser-checks the Sisson building every 30 minutes to monitor even the slightest movement.
Lastly, kudos to the Consigli Construction team for doing all this work while having to step over the super important MWRA water supply pipe that runs through the middle of the construction site.
I feel good about this project, and I hope my neighbors now feel good about too.
Paul Gouthro
Lynn
