PowerOutageHistory
Reliability Grade
F
Least reliable
2014-2025
New Hampshire

Belknap CountyPower Outage History

20142025 · New Hampshire
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What this grade means

Bottom 20% least reliable nationally — frequent and/or long outages. This county ranks in the least reliable fifth of all US counties in our dataset: some combination of frequent outages, long restoration times, or customers affected puts it near the bottom nationally. Backup power is worth prioritizing here rather than treating it as optional.

Takeaway
High outage risk
Reliability Rank
Fuller bar = more reliable
Nationwide9th pct
In New HampshireLeast reliable of 10
See full New Hampshire rankings →
Total events
793
Recorded 2014–2025
Avg duration
4.6 hrs
Per outage event
Longest outage
206 hrs
Single worst event on record
Customers served
32,610
Utility customers in county

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Oct 30, 2017112 hrs20,394 (63%)Tropical Storm Philippe
Apr 4, 202497 hrs20,092 (62%)Winter Storm
Dec 23, 2022206 hrs19,985 (61%)Winter Storm
Nov 26, 201449 hrs13,688 (42%)Winter Storm
Aug 4, 202067 hrs9,254 (28%)Tropical Storm Isaias

Was There an Outage on a Specific Date?

Pick a date to see whether a power outage was recorded for Belknap County, New Hampshire that day.

Over the 12 years from 2014 to 2025, Belknap County recorded 793 distinct power outage events, averaging 4.6 hours per event.

The single worst outage on record in Belknap County started October 30, 2017 (Tropical Storm Philippe), lasting 112 hours and leaving up to 20,394 customers without power (63% of the county) at its peak.

March has historically been the worst month for outages in Belknap County, with 81 events recorded during that month across the dataset.

Based on this history, Belknap County earns a Reliability Grade of F, placing it in the 9th percentile nationally for grid reliability (higher percentile = more reliable).

Similar counties in New Hampshire

Counties with the closest reliability grade and national percentile to Belknap County.

CountyGradeNational percentile
Carroll CountyF11th
Sullivan CountyF16th
Cheshire CountyF18th
Grafton CountyD26th
Rockingham CountyD27th

Most reliable counties nationally

The top 3 counties nationally by reliability grade and percentile.

CountyStateGradeNational percentile
Clay CountySouth DakotaA100th
Clearwater CountyMinnesotaA99th
Limestone CountyAlabamaA99th

Least reliable counties nationally

The bottom 3 counties nationally by reliability grade and percentile.

FAQ

How often does power go out in Belknap County?

Between 2014 and 2025, Belknap County recorded 793 outage events, averaging 4.6 hours each.

What is Belknap County's reliability grade?

Belknap County has a Reliability Grade of F, in the 9th national percentile.

What was the worst power outage in Belknap County?

The worst outage on record started October 30, 2017 (Tropical Storm Philippe), lasting 112 hours and affecting up to 20,394 customers.

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Data: ORNL EAGLE-I Recorded Electricity Outages (2014–2025), CC BY 4.0. Storm names: NOAA Storm Events Database. Last data refresh: 2025. See methodology.