Re: The Boston Arch (Aquarium parking garage)
I think Chiofaro said it would cost $75 million construction costs to build an underground garage at Harbor Towers with 1400/1450 spaces. Because you are digging deeper, right next to the Harbor, the hydrostatic loads increase, and it might cost another $75 million for an additional 1,000 spaces.
Underground parking costs, of the high side, $50,000 per space. 2400 spaces = $120 million, so an additional $30 million because of the harbor site.
$150,000,000 financed at 4.75 percents for 20 years costs $970,000 a month (principal and interest.) Every space in the garage would have to generate $13.50 in gross receipts daily simply for the financing costs. Add to that taxes, insurances, operating costs, maintenance, etc, Chiofaro would be in debtor's prison before the year was out.