PowerOutageHistory
Reliability Grade
C
Average
2015-2025
Illinois

Clark CountyPower Outage History

20152025 · Illinois
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What this grade means

Average — typical outage frequency and duration nationally. This county sits in the middle of the national distribution — its outage frequency and duration over the past 12 years are close to the nationwide median, neither notably better nor worse than most other US counties. A typical amount of backup-power preparedness is reasonable here.

Takeaway
Typical outage risk
Reliability Rank
Fuller bar = more reliable
Nationwide42nd pct
In Illinois#90 of 102
See full Illinois rankings →
Total events
430
Recorded 2015–2025
Avg duration
2.4 hrs
Per outage event
Longest outage
60 hrs
Single worst event on record
Customers served
7,829
Utility customers in county

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Jun 29, 202360 hrs4,592 (59%)Drought
Jun 18, 202526 hrs2,658 (34%)Thunderstorm Wind
Apr 9, 20205 hrs2,376 (30%)Thunderstorm Wind
Jun 1, 20202 hrs2,340 (30%)Unnamed event
Nov 5, 20228 hrs1,788 (23%)Unnamed event

Was There an Outage on a Specific Date?

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

Over the 11 years from 2015 to 2025, Clark County recorded 430 distinct power outage events, averaging 2.4 hours per event.

The single worst outage on record in Clark County started June 29, 2023 (Drought), lasting 60 hours and leaving up to 4,592 customers without power (59% of the county) at its peak.

June has historically been the worst month for outages in Clark County, with 54 events recorded during that month across the dataset.

Based on this history, Clark County earns a Reliability Grade of C, placing it in the 42nd percentile nationally for grid reliability (higher percentile = more reliable).

Similar counties in Illinois

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

CountyGradeNational percentile
Rock Island CountyC41st
Perry CountyC44th
Carroll CountyC45th
Pope CountyC45th
Fayette CountyC46th

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 Clark County?

Between 2015 and 2025, Clark County recorded 430 outage events, averaging 2.4 hours each.

What is Clark County's reliability grade?

Clark County has a Reliability Grade of C, in the 42nd national percentile.

What was the worst power outage in Clark County?

The worst outage on record started June 29, 2023 (Drought), lasting 60 hours and affecting up to 4,592 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.