Phase 1A Electrical Upgrade and Construction Administration Services


Phase 1A Electrical Upgrade and Construction Administration Services

Oakdale Facility, MWRA

About this Project

The original structure at the Oakdale Facility did not contain equipment for the generation of electric power.  In 1949, the facility was modified to include the installation of a turbine and controls, designed to utilize the head differential between the Quabbin and Wachusett Reservoirs, to generate electric power.  Today, the Oakdale facility comprises a hydroelectric power station and its associated 66 kV and 13.8 kV substation.  The facility is located at the outlet of the Quabbin Aqueduct, a 24-mile tunnel that transfers water from the Quabbin Reservoir to the Wachusett Reservoir. The facility is typically operated between March and October.  Power from the generator is provided to an outdoor switchyard which steps the 6.9 kV power up to 66 kV by use of a 4375 KVA transformer.

FST designed a completely new 7.2 kV generator switchgear replacement and completely new 480 volt station service electrical system.  The challenge in designing the replacement was that the new switchgear needed to be located over the floor penetrations to allow the use of existing power cables and control wires.  Since the size of the gear was larger and required additional operational space around it to meet today’s electrical code, FST worked with the gear manufacturer to configure the footprint to meet all requirements.  The station was provided with the operating power that was obtained from the secondary windings of the 66 kV transformer and used when the facility was generating power.  FST also designed a backup 480 volt power service from the local utility for those times when power from the facility is not available.  New energy efficient lighting was also provided.

A new 72 kV oil filled circuit breaker was provided in the substation ahead of the transformer to replace the existing switch. Also included was the replacement of the hook stick isolation switches that were mount above the transformer.

This facility is an historic building and therefore all work required the approval of the Massachusetts Historical Commission.  Meyer & Meyer assisted FST with the architectural improvements required for this project.  LEED elements investigated as part of this project included upgrades to lighting and windows.

More Information

Owner: Massachusetts Water Resources Authority

Location: West Boylston, Massachusetts

Highlights: As a historic structure, all exterior upgrades needed to be approved by the Massachusetts Historical Commission.