Project Highlights

The VELCO Middlebury Substation was originally built in 1969 with various modifications and improvements occurring over the nearly fifty years of service. VELCO conducted a condition assessment of the Substation and identified the need to replace some of the equipment due to condition. The primary deficiency is the control building. 

To correct this deficiency, VELCO proposes to replace the existing control building with a larger control building, and replace and expand a portion of the existing fence to accommodate the new control building on the northeast side of the existing facility. This work will require VELCO to expand the fence by approximately 30 feet on the east side, and approximately 72 feet on the north side to accommodate the new control building. VELCO will address other elements of the Substation by in-kind replacement and modifications of the existing equipment. 

The following upgrades to the VELCO Middlebury Substation will improve reliability of electric facilities serving portions of Vermont. 

  • Replace the existing control building with a larger control building that can accommodate a new protection and control system, redundant AC & DC station services, communication equipment, security systems and new bathroom facilities 
  • Replace the existing perimeter fence and expand the northeast substation yard area to accommodate new control building 
  • Replace water supply & wastewater systems for control building facilities 
  • Installation of a temporary substation and associated temporary access road and temporary fenced in yard to maintain electrical transmission for the Project’s duration (to be returned to existing conditions upon commissioning of the permanent substation) 
  • Redesign existing access road 
  • Replacement of the oil containment system at the transformer (typically maintenance work that does not require any regulatory procedures but is included as a component of this project


  1. Public Outreach

    VELCO project team hosted a public meeting and met with the Town Selectboard to answer questions about the project and listen to community concerns.

  2. Application for Regulatory Approval

    VELCO expects to submit an application for regulatory approval.

  3. Construction

    VELCO anticipates construction to begin Summer 2023.

  4. Commission

    VELCO anticipates the upgraded substation to be commissioned by Winter 2024.

Project Features
Asset Maintenance
Asset Maintenance

Upgrades to existing electric transmission infrastructure.


Transmission additions or upgrades, necessary to ensure the system’s continued reliability. 

Resources & Documents
Advance Notice

The 45-Day Notice package is a detailed project description sent 45 days before filing with the Public Utility Commission to local select boards and other officials to enable community leaders to review and discuss the project’s impacts with residents, and to provide input before the start of formal proceedings before the Commission. The 45-day notice is a requirement of Vermont law and Public Utility Commission rules.

Download the Middlebury Substation Project 45-day notice package. 

Permitting Documents

VELCO filed a petition for Certificate of Public Good (CPG) and supporting documents, seeking approval of the Middlebury Substation Project on January 17, 2023. This library contains all of the public documents filed with the Public Utility Commission as part of VELCO’s petition for a CPG for the Highgate Substation Project. Materials that contain Critical Energy Infrastructure Information are listed but are not available for download. For more information about CEII please contact us.

Public Utility Commission Orders

Middlebury Substation Project: