PowerOutageHistory
Reliability Grade
A
Top tier
2014-2025
Iowa

Dubuque 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
Nationwide91st pct
In Iowa#5 of 99
See full Iowa rankings →
Total events
307
Recorded 2014–2025
Avg duration
1.6 hrs
Per outage event
Longest outage
22 hrs
Single worst event on record
Customers served
58,082
Utility customers in county

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Jul 12, 20178 hrs9,599 (17%)Thunderstorm Wind
Jun 30, 201922 hrs8,367 (14%)Thunderstorm Wind
Jul 15, 202422 hrs7,974 (14%)Flood
Jul 12, 201713 hrs7,770 (13%)Thunderstorm Wind
Jun 24, 20164 hrs6,156 (11%)Unnamed event

Was There an Outage on a Specific Date?

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

Over the 12 years from 2014 to 2025, Dubuque County recorded 307 distinct power outage events, averaging 1.6 hours per event.

The single worst outage on record in Dubuque County started July 12, 2017 (Thunderstorm Wind), lasting 8 hours and leaving up to 9,599 customers without power (17% of the county) at its peak.

June has historically been the worst month for outages in Dubuque County, with 48 events recorded during that month across the dataset.

Based on this history, Dubuque County earns a Reliability Grade of A, placing it in the 91st percentile nationally for grid reliability (higher percentile = more reliable).

Similar counties in Iowa

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

CountyGradeNational percentile
Muscatine CountyA92nd
Adair CountyA90th
Cass CountyA89th
Marion CountyA89th
Carroll CountyA88th

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 Dubuque County?

Between 2014 and 2025, Dubuque County recorded 307 outage events, averaging 1.6 hours each.

What is Dubuque County's reliability grade?

Dubuque County has a Reliability Grade of A, in the 91st national percentile.

What was the worst power outage in Dubuque County?

The worst outage on record started July 12, 2017 (Thunderstorm Wind), lasting 8 hours and affecting up to 9,599 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.