When an outage is reported, a supervisor can evaluate the condition in the suspected manhole on a web-based app, eliminating the need to put the crew at risk by going inside the manhole.

Data Collection in the Capitol’s Underground

July 12, 2021
Pepco rolls out a comprehensive inspection program to safely assess more than 60,000 manholes and vaults in the nation’s capital.

Pepco’s history dates to the late 1800s and today it serves nearly 900,000 customers in Washington, D.C., and parts of Maryland. Like that of many U.S. cities, infrastructure in the cities Pepco serves has gone through many developmental updates through the years. Underground asset information is either inefficiently housed in multiple databases or does not meet the updated scope Pepco requires now.

With the merger of Pepco Holdings Inc. (PHI) into the Exelon family of utilities, distribution preventative maintenance inspection programs were transitioned from being owned by the construction and maintenance operations team to the technical services team within PHI central engineering. Using industry research and best practices benchmarking, the engineering team identified opportunities for improvement in the data collection and rigor of inspection process within the manhole assessment program. A new scope of work for a proof-of-concept pilot program was developed in 2018 to test the feasibility of a more rigorous inspection process within the Pepco service territory for the approximately 60,000 underground structures in the Washington, D.C.-Maryland metropolitan area.

Pepco’s investment in an assessment program of this scale has enabled the utility to develop a preventative maintenance strategy, focus on reliability improvements, create a transactional history of targeted assets and increase safety training on enclosed spaces. An added benefit of this program has been real-time reporting that provides access to 360-degree and thermal photography for crews to review during emergency conditions. For example, when an outage is reported, a supervisor can evaluate the condition in the suspected manhole on a web-based app, eliminating the need to put the crew at risk by going inside the manhole.

Data Collection Platform

The focus of Pepco’s pilot program was to prove accurate inspection data could be collected and shared through different departments with minimal effort. Additionally, the pilot served as a proof of concept for digital photography and 360-degree photography collection, making it possible to see inside structures previously limited to the individuals entering them at the time of inspection. The work required for this program included a comprehensive assessment of the electrical equipment in Pepco-owned manholes and vaults, including but not limited to secondary and primary cables, conduits, manhole structural and hardware accessories, transformers, switches and other equipment. Efforts to support this work included enclosed-space entry of all facilities, occasional pumping of manholes to gain access, comprehensive visual assessments, thermal and conventional digital photography, 360-degree photography and occasional traffic control procedures.

After a successful pilot program, Pepco and Aldridge Electric Inc. entered year two of a multiyear project to assess more than 60,000 manholes and vaults across the nation’s capital. This scope of work was awarded in late 2019 and has led to the expansion of the local workforce and collaboration with community stakeholders and programs to represent the region’s diverse demographic.

The project uses a web-based app to assist in the immediate transfer of information. This new technology was specifically developed by Aldridge’s information technology team based on the needs of Pepco’s request for proposal (RFP). While enclosed-space inspections were not new, the enhanced assessments eliminated the need for paper copies and allowed easy access to equipment records.

The assessment includes general information such as location, size and type as well as expanded information like cable mapping and existing asset condition. A corrective maintenance program was developed from this information to target underperforming feeders, with a focus on the most urgent needs. One of the most recent areas of improvement was the ability to filter the database for joint types. The result is Pepco now has a system of record where certain types and sizes of joints are located, in the event they ever need to be replaced or upgraded.

One of the program’s most significant accomplishments has been the ability to use crews to participate in assessments for feeders that provide power to critical infrastructure. In the early months of the COVID-19 pandemic, the Pepco team identified multiple locations where reliable power was needed in case the role of hospitals was expanded. The assessments enabled Aldridge to review the condition of Pepco’s manholes and feeders as well as make immediate improvements to ensure safe and reliable energy service.

Safety First

Safety is paramount when dealing with underground infrastructure. For use in Pepco’s manhole and vault inspections, a site-specific safety plan was developed so the project team could identify and address project-specific risks and hazards.

Because of the hazardous nature of the work, crews use Pepco’s four key questions during morning briefs as well as Aldridge’s enclosed-space entry checklist to identify hazards and critical tasks. Some of the hazards inside enclosed spaces include exposed conductors, deteriorated structural concerns and the presence of atmospheric gases. The four key safety questions are as follows:

  • What are the critical steps? Discuss the scope of work and sequence of events.
  • What are the error-likely situations?
  • Consider the abilities of the individuals, the changing environment and the time pressure. What is the worst thing that could happen? (For each step, discuss and consider specific problems that could occur if something goes wrong. Speak up if any issues are not addressed.)
  • What defenses are in place? Discuss plans and safety nets based on the answers to the first three questions. Highlight critical inspection and hold points. Speak up if the roles and responsibilities are not clear.

When a crew mobilizes to a jobsite, they set up advanced signage and traffic control, where needed. The streets of any urban environment present multiple challenges, from inquisitive pedestrians to distracted drivers. Setting up a proper jobsite requires minimal disruption to the public while ensuring crews can safely perform their work. Throughout this program, employees perform the same task thousands of times. Therefore, constant interaction occurs between the craft and project management teams to combat potential complacency from repetitive work and keep focused on the importance of the work. Crews engage the office staff’s support for information regarding neighborhoods, parking limitations, pumping restrictions and any access concerns.

Because personal protective equipment (PPE) is the last line of defense, additional steps are taken to review jobsite safety. These include atmospheric measurement of the air space inside the hole prior to removal of the lid, stray voltage detection of the lid and setting up the fall protection railing (manhole guard), including a retrieval system. Crews then open the lid and continuously monitor for harmful gases. A manhole entrant performs a thermographic and visual assessment of the space to detect any hot spots or other abnormal conditions. The proper PPE for crew members starts with two layers of arc-rated clothing, including a fire-retardant balaclava and an arc-rated full-face shield upon initial entry. Other PPE requirements include a safety helmet, safety glasses, approved footwear, hand protection and a full-body harness.

The field’s input into the program’s safety culture has been best demonstrated through project-specific Craft Voice in Safety (CVIS) meetings. Once a month, the craft team meets to discuss leading indicators, review notable safety occurrences and share lessons learned. For instance, because the team uses tablets for the assessment inputs, the need to remove safety gloves was identified as a safety concern. When the group convened, they suggested a glove that met project requirements and could be used with touch-screen devices.

Underground Training Program

Since the pilot program, safety has been more than a priority; it has been a value and the driving force behind safe project execution. All crew members undergo extensive enclosed-space training to mimic real-life conditions in an isolated, safe environment.

Developed for Pepco’s manhole and vault inspections initiative, the Aldridge underground distribution training trailer combines classroom training with hands-on applications in a controlled environment. This mobile facility, along with a trailer used for safe-entry training, is one of a kind and allows a team of subject matter experts (SMEs), each with decades of underground experience, to be certified and provide continuing education to all workers before entry into a Pepco manhole.

In 2020 alone, crew members in the program worked 52,000 hours incident free. This is a testament to the safety culture and the group’s SMEs who emphasize training, career development and implementing best-in-class safety equipment. The need for skilled labor in the Mid-Atlantic has risen significantly during recent years. The enclosed-space training course is often an employee’s first exposure to the dangers of working in a manhole or vault. This innovative training approach and the reinforcement by Pepco’s leadership have enabled the utility to maintain an incident- and injury-free project.

Long-Term Benefits

The long-term benefits of Pepco’s assessment program include a safer, more reliable energy grid with the ability to review manhole content on a web-based platform. The comprehensive assessment of electrical equipment uses the newest technologies to provide an easily searchable database, including photo documentation and real-time deficiency tracking.

The ability to use a predefined defect list ensures reporting is consistent and will aid Pepco in creating future preventative maintenance programs. In addition to collecting large data samples, Pepco now has what it needs to trend data for priority spending projections and planning.

Kyle Arndt is a division manager at Aldridge Electric Inc. He has over 12 years of experience managing electrical infrastructure projects, with the last several years focused on underground infrastructure. He has safely managed projects and programs valued at more than $50 million throughout his career for various utilities across the U.S. Arndt is a graduate of the University of Illinois.

Robert Spelman is supervisor of underground distribution standards at Pepco Holdings Inc. His team is responsible for the specification of distribution equipment, the development and review of construction standards, the analysis of underground equipment failure analysis and the governance and oversight of distribution equipment preventative maintenance programs. Spelman holds a bachelor’s degree in engineering from James Madison University and a master’s degree in power systems engineering from Worcester Polytechnic Institute. He is a registered professional engineer in the District of Columbia.

For More Information:

Aldridge Electric Inc. | www.aldridgegroup.com

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