For Immediate Release - December 12, 2005

DTE Orders Utilities To Upgrade Manhole And Stray Voltage Safety

DTE Orders Utilities To Upgrade Manhole And Stray Voltage Safety

The Massachusetts Department of Telecommunications and Energy ("DTE") today ordered the state's four electric utilities to begin implementing recommendations to bolster manhole and stray voltage safety and detection practices this winter.

The DTE directive comes as two consulting firms hired by the regulator issued their final reports today on these critical public safety concerns. "This is a blueprint for enhanced safety and integrity of our electric underground distribution systems. We need to immediately begin introducing these best practices to mitigate stray voltage and manhole incidents in order to better protect our citizens and their pets from unsafe conditions. State-of-the-art testing equipment, increased frequency of inspections and improved management procedures will help us better ensure the safe delivery of electric utility service," said DTE Chairman Paul G. Afonso.

The DTE ordered the utilities to file Distribution System Safety Plans incorporating each consultant's recommendations by January 10, 2006.Prompted by a series of reports of stray voltage and dislodged manhole covers over the past year and a half, some causing serious injury and extensive property damage, the DTE retained two expert engineering consulting firms, Navigant and Siemens, to review these incidents and make recommendations for corrective actions.

Siemens recommends a more active and anticipatory program to inspect, test and maintain manhole and underground facilities safety that includes:

  • Expanding the definition of manhole events to include smoke, fire, and explosions with or without dislodged manhole covers;
  • Implementing a program for the inspection of all manholes over a five-year period beginning January 1, 2006;
  • Maintaining a database for splice repairs to monitor for possible workmanship issues and related training needs;
  • Performing field failure analysis for all manhole events and preparing annual trend assessments of root-cause failures;
  • Instituting standardized manhole inspection and manhole event data collection forms;
  • Formation of a working group comprised of representatives from the four electric utilities and DTE staff for sharing information on manhole event trends, root cause analyses, results of pilot programs, new technologies and lessons learned.

Navigant recommends targeted stray voltage inspections and testing programs and enhanced reporting of known or potential hazards that includes:

  • Upgrading preventive maintenance plans to include inspection and testing of low voltage, secondary equipment and facilities susceptible to stray voltage. These plans should include voltage testing on a five-year basis at a minimum; inspections scheduled during periods where equipment may have greater susceptibility to stray voltage; a mitigation and remediation plan that includes immediate repair when readings exceed 20 volts and one day repair when readings are between eight and 20 volts
  • Implementation of consistent monitoring and tracking systems that record and document stray voltage events;
  • Submission of reports to the DTE that document and summarize information from the tracking system, including annual reports and event reports;
  • Monitoring and assessing alternative testing methods, including new equipment that will improve inspection efficiency and cost;
  • Promoting safety awareness to the public via mail, bill inserts and contractor bulletins; and
  • Exploring the development of protective equipment with electric equipment suppliers.