Dear editor:
I think that Chris Jennings has a good and valid reason to be very concerned about the underground parking garage proposed by Mr. Hummel for his Queen Street hotel, (letter, June 13, “Serious concerns about planned hotel’s underground parking“).
Without the benefit of a proper geotechnical site investigation and analysis, it is not known whether the groundwater level he refers to is perched, or at the nearby lake level, although it is probably at the latter. Moreover it is not known how pervious to groundwater inflow the underlying subsoils are.
Site dewatering will probably be required, as Mr. Jennings has pointed out, with the inherent risk of damage to adjacent properties.
There may also be a need for a steel sheet pile cofferdam with some vibration risk to adjacent properties during installation or even a concrete slurry wall.
This would be an expensive undertaking, making an above-grade solution an attractive cost alternative to the developer. A geotechnical investigation (if one does not already exist ) would likely provide answers to many of the unknowns.
The only indication at this point is the potential for it being a serious and expensive issue and as such should be examined carefully by town staff and council alike so they are fully aware of any resulting consequences.
This, of course, is in addition to the historical and heritage aspects of NOTL that are of great interest and concern to residents in public debate, but are ignored by this developer and others.
Derek Collins
NOTL