Underground transformer explosion closes street in Norwalk
Jan 2020Published 25 Sept 2026Responsible editor: Chief Editor
- Where
- Sidewalk electrical vault, 44 North Main Street, Norwalk
- Operator
- SNEW
- What
- Underground transformer fire and explosion
- Injuries
- None reported
- Response
- Norwalk firefighters and SNEW crews contained the fire
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Companies named in the reporting of this entry (being named is not a finding of fault): SNEW
What happened
An underground transformer fire and explosion occurred at about 9:35 a.m. on 21 January 2020 in front of 44 North Main Street in Norwalk. The blast blew open the doors of a sidewalk electrical vault and sent thick black smoke into the air. It caused a power outage in South Norwalk and North Main Street was closed for about two hours. Norwalk firefighters and SNEW crews contained the fire after power to the area was cut.
No buildings were damaged and there were no injuries, although one person nearby had a close call and was uninjured. By about 11:30 a.m. SNEW said most customers had been restored by isolation and switching. Some customers on and around North Main Street were to remain without power while the damaged transformer was temporarily replaced, and no time was given. Buildings along North Main Street were expected to be without power for at least the rest of the day. A reported water main cutoff was later corrected as a planned event unrelated to the explosion.
Contributing factors
The cause of the explosion was not reported.
Lessons learned
- An underground transformer failure in a sidewalk vault can blow the doors and force a street closure, so operators must isolate the area and exclude the public at once.
- Isolation and switching can restore supply to most customers while the damaged unit stays off, so operators must state clearly which customers remain without power.
More lessons on electrical protection and isolation, from every incident on the register.
Not yet known
- Cause of the explosion
- Transformer model and age
- Time to replace the damaged unit
- Cost of the damage and outage
This entry is updated when these are reported. Get an alert for the next one like it.
Source
Other entries that name Norwalk
Published 2026-09-25. Written from public reporting. Descriptive, not investigative. See the data accuracy disclaimer.
