PowerOutageHistory
Reliability Grade
A
Top tier
2014-2025
Iowa

Clayton CountyPower Outage History

20142025 · Iowa
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What this grade means

Top 20% most reliable nationally — infrequent, short outages. This county ranks in the most reliable fifth of all US counties in our dataset, based on 12 years of real DOE outage records: outages happen less often here, and when they do occur they tend to be resolved quickly compared to the rest of the country. Baseline outage risk is low, though a severe local storm can still occasionally cause a longer-than-usual outage regardless of the long-term track record.

Takeaway
Low outage risk
Reliability Rank
Fuller bar = more reliable
Nationwide80th pct
In Iowa#29 of 99
See full Iowa rankings →
Total events
253
Recorded 2014–2025
Avg duration
2.5 hrs
Per outage event
Longest outage
27 hrs
Single worst event on record
Customers served
10,667
Utility customers in county

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Jul 19, 201727 hrs4,994 (47%)Thunderstorm Wind
Jun 22, 201512 hrs3,186 (30%)Hail
Jan 18, 20201 hrs2,876 (27%)Winter Storm
Jan 25, 20192 hrs2,712 (25%)Heavy Snow
Mar 6, 20182 hrs1,941 (18%)Unnamed event

Was There an Outage on a Specific Date?

Pick a date to see whether a power outage was recorded for Clayton County, Iowa that day.

Over the 12 years from 2014 to 2025, Clayton County recorded 253 distinct power outage events, averaging 2.5 hours per event.

The single worst outage on record in Clayton County started July 19, 2017 (Thunderstorm Wind), lasting 27 hours and leaving up to 4,994 customers without power (47% of the county) at its peak.

July has historically been the worst month for outages in Clayton County, with 47 events recorded during that month across the dataset.

Based on this history, Clayton County earns a Reliability Grade of A, placing it in the 80th percentile nationally for grid reliability (higher percentile = more reliable).

Similar counties in Iowa

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

CountyGradeNational percentile
Clarke CountyA80th
Cerro Gordo CountyA80th
Hamilton CountyB80th
Madison CountyA81st
Decatur CountyB79th

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 Clayton County?

Between 2014 and 2025, Clayton County recorded 253 outage events, averaging 2.5 hours each.

What is Clayton County's reliability grade?

Clayton County has a Reliability Grade of A, in the 80th national percentile.

What was the worst power outage in Clayton County?

The worst outage on record started July 19, 2017 (Thunderstorm Wind), lasting 27 hours and affecting up to 4,994 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.