Ronkonkoma Substation Upgrades and New Distribution Feeders

Project Specifics

PSEG Long Island continues to make improvements to its energy infrastructure in order to increase reliability and minimize outages affecting our customers. We are committed to making every effort to ensure our grid is resilient during storms. Over the coming months, you will see workers strengthening the transmission and distribution lines in your area. While this work is being performed, traffic and parking may be impacted along the route.

Project Timeline

Construction is expected to begin in the end of September and take several months to complete. 

Project Scope

PSEG Long Island is planning the installation of three underground 13kV feeders that will originate at the Long Island Power Authority’s (LIPA's) Ronkonkoma Substation. In addition, electrical equipment will be installed within the limits of the Ronkonkoma Substation to accommodate the necessary electrical connections and supply. Wood transmission poles within the substation will be replaced with steel poles of similar size.

In addition to the underground distribution feeder installation, electrical equipment will be installed within the limits of the Ronkonkoma Substation and on the west side of the LIRR Ronkonkoma Station on Railroad Avenue, and underground interconnections will be made as needed. Equipment installations will include the installation of new transformers, switchgears, a control house containing battery enclosures, switching equipment and support structures. Supporting work comprised of in-kind pole replacements and reconductoring will also occur within the project area.

Transmission Work
Three (3) transmission poles will be replaced and two (2) transmission poles will be removed. The three existing wood transmission poles to be replaced are all located within the Ronkonkoma Substation. The three transmission poles will be replaced with steel poles and result in height increases of less than 10 feet after embedment. New equipment to be installed within the existing Ronkonkoma Substation will be one (1) 138-13kV transformer, one (1) control house that includes two (2) battery enclosures, one (1) 13 kV switchgear, three (3) 138kV gas circuit breakers, four (4) gang operated disconnect switches, two (2) motor operated circuit switches, two (2) potential transformers and one (1) control potential transformers. A series of trenches will connect the new equipment to the existing equipment within the substation.

Location of the site or right-of-way:
Transmission work and distribution feeders: Within the Ronkonkoma Substation, Hawkins Avenue, in the hamlet of Lake Ronkonkoma, Town of Brookhaven.

C&R work:
Pole replacements and reconductoring in hamlet of Ronkonkoma, Town of Islip and hamlet of Lake Ronkonkoma, Town of Brookhaven.

Description of the utility transmission facilities to be built:
This work includes the replacement and removal of transmission poles within the Ronkonkoma Substation on Hawkins Avenue, hamlet of Lake Ronkonkoma, Town of Brookhaven.  

Why does PSEG Long Island need to perform this work? 
In order to ensure sufficient and reliable power supply to the Long Island Railroad (LIRR) facility expansion, Ronkonkoma Hub and a proposed mixed-use development, and to prevent potential overloads on existing banks and feeders, PSEG Long Island is planning the installation of three underground 13kV feeders that will originate at the Long Island Power Authority’s (LIPA's) Ronkonkoma Substation.

Alternative overhead transmission line routes were assessed:
No alternative transmission routes were assessed.

Why is the proposed location best suited for the facility? 
The transmission line and substation already exist at this location.

SEQRA Environmental Assessment 

Distribution Work
Two new 13kV distribution feeder cables will exit the east side of the Ronkonkoma Substation and will each be approximately 4,840 linear feet in length. The feeders will exit east from the existing Ronkonkoma Substation on to Hawkins Avenue, then will travel east on Thorne Street, south on Carroll Avenue, then continue south beneath the Long Island Expressway, will proceed south on Carroll Avenue, will then travel through the intersection of Carroll Avenue and Railroad Avenue, turn west on Railroad Avenue, turn south on the west side of the LIRR Ronkonkoma station, and will terminate south of the LIRR tracks at one new and one existing padmount switchgear.

The new 13kV distribution feeder that exits the north side of the Ronkonkoma Substation will be approximately 1,320 linear feet in length. The feeder will exit to the north through the LIPA owned right-of-way (ROW) and on to Church Street, then continue west on Church Street, will then turn right onto Ronkonkoma Avenue, and will terminate at Pole 82 on the east side of Ronkonkoma Avenue at a riser connecting to the existing overhead circuit.

The three distribution exit feeders will be installed in 6” conduits. The distribution feeders will be installed via horizontal directional drilling (HDD), with the exception of select portions within the limits of the Ronkonkoma Substation that will be installed via open trench. A total of 17 manholes will be installed along the feeder routes. All drill pits will be completed within paved areas. Supporting work comprised of in-kind pole replacements and reconductoring will occur on Smithtown Avenue, Long Island Motor Parkway, Belle Avenue, Fir Grove Road, Michigan Street, Pond Road, Ronkonkoma Avenue, Union Avenue and Carroll Avenue.

Frequently Asked Questions

  • What are the work hours?
    Crews will work Monday – Friday, 7 a.m. – 3 p.m.
  • Will there be tree trimming?
    Trees growing near power lines significantly increase the chance of power outages and pose safety risks. As we expand and improve our electric circuits, we will trim trees, where necessary, following our utility best practice model (ANSI A300 standards as well as the Best Management Practices Tree Pruning publication): 8 feet to each side; 12 feet above; and 10 feet below the line.
  • Will there be any power outages?
    PSEG Long Island does not anticipate any power outages associated with this project. However, if the need for an outage arises, customers will be notified in advance.
  • Will there be any traffic interruptions?
    There will be some traffic disruptions along the route when work is in progress. To ensure traffic moves safely, PSEG Long Island will provide cones, flagmen and signage at the work sites.
  • A brief note on COVID-19
    PSEG Long Island is deeply committed to the health, safety and wellbeing of our customers, employees and our communities. We ask that customers remain in their homes while crews are working nearby. If customers must speak with our crews, we ask that they practice responsible “social distancing” and remain at least 6 feet away to ensure the health of everyone involved. Any contractors that may be used for this project has provided PSEG Long Island with its safety plan, which meets current regulatory requirements with respect to COVID-19, including social distancing measures. PSEG Long Island, like many companies, has robust business continuity plans and planning processes that predate the COVID-19 outbreak. We continuously review those plans to ensure their effectiveness in this situation and are implementing them accordingly. In addition, we are leveraging the guidance of the CDC and state and local authorities in the areas we operate. At PSEG Long Island, we know that our customers rely on us to power their lives and businesses. We are doing our part in fulfilling this commitment. For more information, please visit:
  • How can I get more information or leave feedback?
    If you have further questions, please contact PSEG Long Island Customer Service at 1-800-490-0025 between the hours of 8 a.m. and 8 p.m. If you would like to share your comments on the project, please email them to:

As always, customer and employee safety is our primary concern. Please be cautious when traveling near our construction work zones.

Posted Date: 09/25/20