BY MIKE HUDSON
Greenman Pedersen, the Albany based engineering and construction firm overseeing the Peace Bridge project in Buffalo, is also in line to receive a healthy chunk of the $4.9 million design contract for the Goat Island bridge replacement project.
The firm signed off on a 131-page preliminary Design Report and Environmental Assessment on the project, which cost $2.4 million, and states that the final design report will cost another $2.5 million. The project itself is estimated at between $21.37 million and $37.32 million, and will involve halting the flow of water over the American Falls for at least five and perhaps as long as nine months.
The longer of the two bridges is 424 feet while the shorter span measures 245 feet in length, the report states. Several alternatives are listed, ranging from doing nothing but ongoing maintenance to keep the bridges open to building two completely new spans.
The report states that the American Falls must be dewatered to allow for the demolition of the existing bridges and construction of the replacements. It does not say if engineers and construction workers managed, 115 years ago in 1901, to build the current bridges without dewatering the falls.
In fact, the flow of water over the falls was much greater in 1901, prior to the hydroelectric diversions associated with the Niagara Power Project.
“Dewatering is expected initially (to) be a tourism draw (a once in a lifetime opportunity to see the falls and river channel without water), but after some period of time could negatively impact park attendance, particularly during the summer tourist season,” the report states.
No alternative to dewatering is considered, other than localized dewatering around the pilings and piers as they are constructed, which the report says would be cost prohibitive.
And the reality is that a dewatered falls is not a “once in a lifetime” event, since the falls were shut off in 1969 so that geologists could examine the condition of the underlying bedrock.
At that time, human skeletons, thousands of coins, guns and other weapons were recovered by workers.
Ultimately, the report recommends construction of a large cofferdam at the upstream tip of Goat Island to shut off the flow of water to the American and Bridal Veil falls and diverting it to the Canadian Falls.
According to the report, planning for the project began in 2005, after the bridges were closed and the temporary bridges opened. At that time, a study conducted by Cannon Design recommended the bridges be replaced, based on the deteriorating condition of the arches and the concrete piers that support the spans.
In 2009, Bergmann Associates and L.P. Ciminelli undertook another study to determine what kind of bridges would make for suitable replacements, along with an assessment of various dewatering options to be used during construction.
Finally, in 2012, State Parks signed a memorandum of understanding with the state Department of Transportation to provide for scoping, management, bidding and administration.