Cables to be rerouted as part of Walk Bridge project
Eversource electric cables won’t be the only utility lines needing relocation due to the Connecticut Department of Transportation’s upcoming replacement of the Walk Bridge over the Norwalk River in Norwalk.
This month, the Norwalk Common Council authorized Mayor Harry Rilling to write the U.S. Army Corps of Engineers and Connecticut Department of Transportation, expressing the city’s support for the temporary and permanent relocation of Metro-North Railroad’s transmission, communication and signal cables.
“They’re going to put in temporaries now — one for the communications for Metro-North, the other for power of the bridge so it will continue to work,” said Norwalk Director of Public Works Bruce Chimento. Afterward “the temporary cables will be removed, except for power to the bridge. That will stay to the north (of the bridge).”
As part of the MetroNorth communications-and-signal systems upgrades along the New Haven Line, a new submarine cable crossing the Norwalk River will be installed. The project is part of the CP243 project, an upgrade to track and signals being done in advance of the Walk Bridge replacement.
“Like the overarching Walk Bridge program, the installation of this submarine cable is one more element of the project designed to enhance reliability along the New Haven Line corridor,” said Judd Everhart, DOT spokesman. “We have learned the hard way what happens when this bridge fails to open and close properly. Our customers expect good service and we want them to have confidence that we’re working hard to improve the overall customer experience. This is one small piece of that effort.”
The proposed submarine cable will comprise seven 4-inch diameter individual cables that will be bundled and placed within a trench, excavated seven feet below the riverbed, north of the Walk Bridge.
Maps provided to the council show the proposed new submarine cables placed in the same location as the existing cable — just north of the bridge.
The anticipated construction schedule is between Dec. 1, 2018, and Jan. 31, 2019, or alternatively, between Dec. 1, 2019, and Jan. 31, 2020. Dredging is restricted to those periods under U.S. Army Corps guidelines.
During the construction, the contractor will block one or more navigation channels. Emergency vessels, including police and fire along with small boats, will be able to pass through the one open channel. Any vessels requiring opening of the Walk Bridge will require four hours advance notice, according to a summary of the project provided to the council.
The trench excavation and cable laying will occur only during incoming and slack flood tides as requested by the Norwalk Shellfish and Norwalk Harbor commissions.
“That was the principle concern of the Shellfish Commission and the Harbor Commission — to avoid any contaminated sediment being carried downstream,” said Geoffrey Steadman, planning consultant for the Harbor Commission. “The DOT adjusted their plan to do that.”
The estimated $1.24 million submarine cable project is separate from Eversource Energy’s plan to relocate 115,000-volt transmission lines that now run atop the Walk Bridge. The plan to run those below the riverbed, south of the bridge and through the area of the Norwalk Visitors Docks at Veterans Memorial Park has caused concern among harbor commissioners.