Norwalk Harbor Management Commission Application Review Committee Chairman John Pinto talks about plans for the Walk Bridge reconstruction on Sept. 27 in City Hall.
A diagram showing the planned location of transmission lines under the Norwalk River.NORWALK, Conn. — The planned route for underwater high voltage electrical cables goes right under the newly reconstructed Veterans Park visitor docks, Harbor Management Commission members said.
This will limit how the dock can be rebuilt in the future, John Pinto said, questioning the effect of steel pilings in close proximity to cables carrying 115 Kilovolts. Another concern is the possible effect of magnetic fields on marine flora and fauna in the harbor.
“It may be of minor concern but according to current literature, many marine species not only detect but also respond to electromagnetic fields. Given our current circumstance, I don’t know whether this would be a good or bad thing or even to what extend an electromagnetic field would be generated,” Pinto said in a Monday email.
The Commission on Sept. 27 discussed the plans developed by Eversource and the city in conjunction with the state’s planned reconstruction of the Walk Bridge, the aged railroad bridge over the Norwalk River, which caused chaos for thousands of commuters when it malfunctioned in 2014.
Before construction can begin, the Connecticut Department of Transportation (ConnDOT) needs to remove the transmission lines that run over the Walk Bridge. Various routes were considered, with Norwalk officials rejecting the idea of running the cables on monopoles from the bridge to Oyster Shell Park, as it was thought to ruin the view of the harbor.
Eversource plans to dig a trench from the Norwalk Police station on Monroe Street, up Elizabeth Street and over to 90 Water St., Pinto and other officials said. The cables will go through that trench and then under the Norwalk River, under Veterans Park, down the road and surface at the railroad tracks at Van Zant Street.
Pinto, Professor of Biochemistry and Molecular Biology at New York Medical College in Valhalla, N.Y., on Sept. 27 said that there had been a recent discussion with Eversource about this plan.
“The main concern, that certainly we had, was what is going to happen under the harbor,” Pinto said. “The boring is going to have to be more of an art. They are going to go down from the harbor edge… They are going to come up close to the visitor’s dock. The concern that we had was how do we prepare for that? We are going to be limited by what we can do in that area and where their eventual pilings are going to be. Because they are reconstructing that.”
A plan to bore under the Norwalk River.Pinto expressed admiration for the planned construction techniques, as the cable would be more than 40 feet down in the middle of the river, in a bow-shape. A horizontal directional drill would create a pilot hole, then a larger tunnel would be reamed for the pipe. The cables would be pulled through once the pipe is installed.
There were seven designs considered, Pinto said. The cable needs to go in a straight line.
“There are going to be two conduits side by side,” he said. “The positioning of those pilings are going to be critical. It’s going to be limited to what design we can have there.”
Eversource might say there will be no problems in the future, but that’s what the Harbor Commission was told in the mid-90s when NorthEast Utilities got permission to place three new power lines from Manresa Island to Long Island, in a trench six feet below the harbor bottom, he said.
“They assured us, ‘no problem.’ Now we have a problem,” Pinto said.
On Monday, Pinto explained, “Recently, Eversource, who owns the cables came to the Commission claiming they are having a ‘scouring’ problem caused by shellfisherman scraping their nets over the surface close to where the cables are located. Eversource has an application pending with DEEP to install marker buoys to warn fishermen of the location of these cable lines. At the time these cables were to be installed, NorthEast Utilities (owner at that time), assured the NHM Commission that there would be no future problems with these cables once they were submerged under the harbor. Fast forward to today, now we’re having an issue with them….All be it, a minor one, provided a series of marker buoys are installed across Norwalk Harbor in the Manresa area.”
“I used the previous issue to illustrate a point of them telling us one thing and finding out later there is a problem,” he said. “I think we need to know the future impacts on the harbor and future ability to replace/refurbish the Visitor’s Docks within this area. High powered transmission lines are one of the major sources of magnetic fields. I think we need to know the impacts of these lines on the marine flora and fauna in the harbor as well as the impacts on future construction and boating within the area.”
On Sept. 27, Pinto said the Environmental Protection Agency has an issue with high tension wires going underneath the water.
“Hopefully water won’t touch that but there is still a high tension current going through there that very well may affect the environment in that area,” he said.
Pinto described a thick EPA document on the topic; asked about that he provided two smaller documents, including a 2012 study of the effects of high voltage transmission lines on humans and plants.
“The electromagnetic field from high power transmission lines affects the growth of plants,” the 2012 study states.
High voltage lines effect on human and plants 2014
Transmission line EMF interference with buried pipeline 2003
Eversource will need approval from the Connecticut Siting Council; Mayor Harry Rilling said Monday that he plans to request a public hearing on the plan.
Construction is expected in late 2018, according to an Eversource document.
Eversource cable Norwalk River 17-0927
“Regarding the placement of piles to secure the visitor’s docks, we need to know what distance these pilings (which will be steel construction, not wood) have to be away from these buried cables,” Pinto wrote Monday. “If they list or move as a result of wind and wave action or as a result of unforeseen dock movement, we should know what the impacts would be. … As always, to be continued.”
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