ADDISON — The cost for replacing the Champlain Bridge will be a minimum of $67 million and take at least 22 months to build, according to a preliminary report released last week by an engineering firm for the New York State Department of Transportation.
The assessment by HNTB New York Engineering and Architecture also analyzed the pros and cons of providing a temporary fix for the 2,187-foot span, and of rehabilitating the 80-year-old landmark.
Officials from New York and Vermont closed the bridge between Addison, Vt., and Crown Point, N.Y., on Oct. 16 after inspection revealed deterioration in two of its piers. Since then, drivers who had used the bridge for 3,400 trips a day across Lake Champlain have either used vehicle ferries at Shoreham and Charlotte or a pedestrian ferry at Basin Harbor in Ferrisburgh.
HNTB in its report said the bridge piers could be replaced in only nine months at a cost of more than $20 million. But this solution would still require an additional $14 million to repair the structural steel and paint the bridge, and a complete rehabilitation or replacement of the bridge would be necessary in five year.
Another option, complete rehabilitation, would maintain an historic landmark. But the engineers said it would cost $84 million and disrupt traffic for 30 months. In addition, this option would mean the bridge in the future would require expensive maintenance and would last an estimated 50 years.
The $67 million fix would have the benefits of improved safety and reliability, lower future maintenance costs and it would give access to pedestrians and bicycles. It would also last 75 years.
“Given the risks associated with rehabilitation, together with the reduced level of safety of the rehabilitated structure as compared to a new bridge after completion, we recommend that rehabilitation options be dismissed and a permanent on-site replacement be advanced,” HNTB concluded.
“Given the long detour lengths, the importance of the bridge to the regional economy, and the need for a safe reliable crossing at this location for many years to come, both temporary and permanent rehabilitation strategies are inadequate for this crossing.”
The engineering firm also recommended that the remaining superstructure be demolished “in a controlled manner as soon as practical to eliminate the risk of sudden, potentially catastrophic, failure. Piece by piece superstructure demolition with water or structure-based cranes is inappropriate, given the overall fragility of the structure.”
In the meantime, transportation officials last week said they are moving with all due speed to set up a new temporary ferry service about 1,000 yards south of the Champlain Bridge.
On Friday, the NYSDOT said it has determined that the site just south of the existing bridge where temporary ferry service is being developed is a more feasible site for a temporary bridge than the site at the hamlet of Crown Point.
“Future assessment of a temporary bridge will focus on the temporary ferry site,” said a note on the department’s Web site. “This will not conflict with the proposed ferry service.”
A toll-free hotline for information about the bridge closure (1-888-769-7243) will remain open, Monday through Friday, from 9 a.m. to 5 p.m. Those calling from the 518 area code in New York may dial 518-485-1159. Further, regular e-mail updates are being sent to residents of both states who have signed up to receive them. These updates can be accessed by visiting the respective state transportation agency Web sites at www.lcbclosure.org in New York and www.aot.state.vt.us in Vermont.
The full engineering report on the condition of the Champlain Bridge is available at www.nysdot.gov.