Cass CountyPower Outage History
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.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Apr 10, 2023 | <1 hr | 4,486 (55%) | Unnamed event |
| Nov 28, 2016 | 2 hrs | 1,930 (24%) | Unnamed event |
| Nov 1, 2024 | <1 hr | 1,919 (24%) | Unnamed event |
| Dec 1, 2018 | 5 hrs | 1,631 (20%) | Tornado |
| May 15, 2015 | 1 hrs | 1,523 (19%) | Unnamed event |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Cass County, Illinois that day.
Over the 11 years from 2015 to 2025, Cass County recorded 115 distinct power outage events, averaging 2.3 hours per event.
The single worst outage on record in Cass County started April 10, 2023, lasting less than 1 hour and leaving up to 4,486 customers without power (55% of the county) at its peak.
June has historically been the worst month for outages in Cass County, with 22 events recorded during that month across the dataset.
Based on this history, Cass County earns a Reliability Grade of A, placing it in the 92nd percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Illinois
Counties with the closest reliability grade and national percentile to Cass County.
| County | Grade | National percentile |
|---|---|---|
| Lake County | A | 92nd |
| Kendall County | A | 93rd |
| Clay County | A | 91st |
| Edwards County | A | 91st |
| Schuyler County | A | 91st |
Most reliable counties nationally
The top 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | South Dakota | A | 100th |
| Clearwater County | Minnesota | A | 99th |
| Limestone County | Alabama | A | 99th |
Least reliable counties nationally
The bottom 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | West Virginia | F | 0th |
| Lincoln County | West Virginia | F | 0th |
| Cameron Parish | Louisiana | F | 0th |
FAQ
How often does power go out in Cass County?
Between 2015 and 2025, Cass County recorded 115 outage events, averaging 2.3 hours each.
What is Cass County's reliability grade?
Cass County has a Reliability Grade of A, in the 92nd national percentile.
What was the worst power outage in Cass County?
The worst outage on record started April 10, 2023, lasting less than 1 hour and affecting up to 4,486 customers.