A JCP&L crew working outside RBC at about 4:35 Monday morning. (Photo by John T. Ward. Click to enlarge)

By JOHN T. WARD

Utility workers restored electrical power to downtown Red Bank Sunday night following a series of underground transformer explosions that sent manhole covers and bricks flying at mid-afternoon.

No one was reported injured in the blasts, which occurred in two curbside service pits located about 100 feet apart outside the Red Bank Catholic High School/Saint James Church complex on Broad Street, with the first of four explosions reported at about 3:06 p.m.

Smoke poured from a transformer pit outside the high school and church Sunday afternoon. Authorities said the first explosion occurred in the pit, followed by three blasts in a second pit 100 feet to the south. (Photo by John T. Ward. Click to enlarge)

Shortly before 10 p.m., only two customers of Jersey Central Power & Light remained without electrical service, borough police said in an announcement. The high school and adjoining St. James Elementary School, however, were to remain closed Monday “so as not to impede the progress of repair crews,” the announcement said.

The blasts occurred on a quiet Sunday afternoon at the end of a holiday weekend. But numerous restaurants and other businesses were open, including a hair salon next door to the high school. St. James Church had a mass scheduled for 5:30 p.m. The explosions occurred just feet away from the church steps.

The announcement attributed the cause of the explosions to “transformer failures.”

According to the website of Popular Mechanics magazine, “all it takes is a trigger, a corroded or faulty wire” to create a short-circuit inside a transformer, which regulates voltage between the power grid and customer equipment. In the event of a short circuit, mineral oil stored inside the transformer to keep circuits cool can ignite, causing an explosion, according to the report.

In underground transformer pits, equipment degradation may be caused by salt used to keep streets and sidewalks ice-free in winter, the magazine said.

According to website  of Transformer Protector, a company that manufactures safety equipment for the utility industry, transformers “can only withstand a small overpressure and are not designed as pressure vessels according to ASME Codes and Controls. Consequently, transformers have proven to be very dangerous. Because transformer standards describe electrical requirements but do not cover mechanical design.”

Five years ago, an underground electrical transformer exploded in the Chelsea section of Manhattan, sending a fireball seven stories into the air, according to the New York Times. No one was injured.

The downtown portion of Broad Street is free of utility poles because all the electrical service is underground, according to borough officials.

The borough recently won a key ruling in a longstanding dispute with New Jersey Natural Gas Company over the company’s decision to move gas regulators from underground pits to above-ground placements adjoining storefronts, which the town objected to. The electrical utilities were not part of that dispute.