In 1939, World War II began, LaGuardia Airport opened in New York and the Wizard of Oz premiered.
It's also the same year that more than two miles of transmission lines were installed to power downtown Providence.
Eighty-two years later, those lines, as well as subsequent lines installed in 1946, have experienced an increasing number of failures due to the gradual deterioration of the cables and accessories.
This spring, National Grid's working around the clock on infrastructure upgrades to power the downtown area.
'The Power4Tomorrow Downtown Electric Reliability Project in Providence is replacing approximately two miles of existing 115kV underground transmission lines to power the downtown area and to maintain a reliable electric supply for our Providence customers,' said National Grid Project Manager George Maximovich.
The project is located entirely within existing rights-of-way including travel lanes and sidewalks, along South Main Street, North Main Street, Charles Street and Admiral Street. The transmission lines being replaced are located between the corner of Clarkson Street and Admiral Street to the north and Dollar Street and South Main Street to the south, all in Providence.
Many of the existing manhole locations are being replaced with duct bank (underground conduit), meaning approximately 40 less manholes along the project route. The existing manholes are being phased out because they are not compatible in size and layout for modern cables. Eight new manhole installations now grace Dollar Street, North Main at Steeple, North Main at Cady, Charles Street at Mill and Randall Streets, and Admiral Street at Whipple Street. Modern underground cables are being installed by re-using roughly 60 percent of the existing duct bank.
'There are a host of benefits with the Power4Tomorrow Downtown Electric Reliability Project,' said Maximovich 'The installation of modern cables typically requires less maintenance, increasing the capacity of the transmission lines provides a wider swath of transmission flexibility in Providence and it retires 70 percent of the manholes along the project route.'
It's a complex project and the team has encountered many challenges along the way. Originally, crews planned to pull new cable through the existing duct bank that runs under Route 146, the point at which the underground lines meet the overhead transmission that runs parallel to the highway. Unfortunately, National Grid cannot reuse the existing duct bank, so the engineering team has designed a new approach to use directional drilling under the highway for this portion of the project. Currently National Grid is in the permitting phase for the new design and should begin this piece of the construction late this summer.
The project route runs along some of the oldest streets in the city. Consequently, the gas infrastructure in this area was installed in the late 1800's and early 1920's. Since final road restoration requires curb to curb paving, the gas side of the business is replacing the gas main in this area before final paving. National Grid is currently working on North Main Street near Steeple Street and will be continuing to the intersection of Mill Street.
Concurrently, the Company is completing electric distribution work on Charles Street from Orms to the on-ramp to I-95. Community and Customer Manager, Marisa Albanese said 'I can only compare our efforts on these three discreet projects to the choreography required of a carefully orchestrated dance. There are a series of moving targets and unknown variables that arise every day. Kudos to the project teams for their flexibility and constant communication with each other. While the work is disruptive right now, we should not need to excavate in these areas for years.' Extensive equipment upgrades are also taking place inside of the Admiral Street Cable terminal and we already concluded the equipment upgrades at Franklin Square Substation.
As the project route gets closer to completion, the project route will be repaved, and sidewalks will be restored. Construction is expected to be complete in the winter of this year (2021) and the new underground cables will be in operation in the earlier months of 2022. Some restoration started this spring and the rest will occur next summer.
National Grid plc published this content on 14 June 2021 and is solely responsible for the information contained therein. Distributed by Public, unedited and unaltered, on 14 June 2021 15:07:02 UTC.