County annual report · FIPS 17163
2018 St. Clair County, IL Power Outage Report
In 2018, customers in St. Clair County, IL went without power for an average of 8.1 hours, a total of 763K customer-hours (Illinois average 2.5 hours). That ranks 10th worst of 102 Illinois counties and 683rd of 2,798 nationally.
Compared with IL, the US and 2017
Coverage line is EAGLE-I's share of Illinois customers tracked each year.
Biggest outages in St. Clair County, 2018
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | June 26, 2018 09:45 | July 5, 2018 04:00 | 8d 18h | 28,750 | 562K |
| 2 | July 14, 2018 18:30 | July 18, 2018 23:15 | 4d 4h | 5,927 | 24K |
| 3 | January 6, 2018 11:00 | January 8, 2018 13:15 | 2d 2h | 4,896 | 9,787 |
| 4 | February 14, 2018 07:30 | February 14, 2018 18:30 | 11h | 3,093 | 7,070 |
| 5 | January 1, 2018 06:15 | January 1, 2018 23:15 | 17h | 2,509 | 15K |
| 6 | April 10, 2018 13:00 | April 11, 2018 22:00 | 1d 9h | 2,476 | 3,147 |
| 7 | June 8, 2018 14:00 | June 9, 2018 08:30 | 18h 30m | 2,381 | 708 |
| 8 | April 22, 2018 12:00 | April 22, 2018 22:00 | 10h | 2,127 | 8,418 |
| 9 | November 15, 2018 11:00 | November 15, 2018 20:15 | 9h 15m | 2,099 | 12K |
| 10 | May 31, 2018 04:15 | May 31, 2018 08:15 | 4h | 1,921 | 6,293 |
Outage episodes by size in 2018: 79 reached 100+ customers, 16 reached 1,000+ customers, 1 reached 10,000+ customers.
Utility reliability filed with the EIA
SAIDI (average outage time per customer) and SAIFI (average interruptions per customer) that utilities serving St. Clair County reported on EIA Form 861 for 2018, or their most recent earlier filing. Utility-wide figures, not county-specific.
| Utility | EIA year | SAIDI | SAIFI | SAIDI excl. major events | SAIFI excl. major events |
|---|---|---|---|---|---|
| Ameren Illinois Company | 2018 | 3.5 hrs | 1.06 | 1.8 hrs | 0.90 |
| Southwestern Electric Coop Inc - (IL) | 2018 | 4.6 hrs | 1.89 | 4.6 hrs | 1.89 |
| Tri-County Electric Coop, Inc (IL) | 2018 | 4.7 hrs | 1.74 | 83 min | 0.81 |
| Monroe County Elec Coop, Inc | 2018 | 1.6 hrs | 0.84 | 1.6 hrs | 0.84 |
| Ameren | - | - | - | - | - |
| Egyptian Electric Coop Assn | - | - | - | - | - |
| Clinton County Elec Coop, Inc | - | - | - | - | - |
| City of Highland | - | - | - | - | - |
| City of Mascoutah - (IL) | - | - | - | - | - |
| Village of Freeburg - (IL) | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 92% of Illinois's customers in 2018; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 94,355 customers (ORNL modeled county customer count), including major storm days. It is comparable across counties but is not the SAIDI a utility files.
- An outage event is a continuous stretch with customers out; counts at 100, 1,000 and 10,000+ use its peak.
- Years loaded: 2015–2025. St. Clair County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), St. Clair County, IL annual power outage report, 2018, data as of Oct 3, 2026 02:41 UTC, sources: DOE EAGLE-I (https://eagle-i.doe.gov/); EAGLE-I modeled customer counts (MCC) (https://figshare.com/); EIA Form 861 (utility reliability) (https://www.eia.gov/electricity/data/eia861/). https://massoutage.com/reports/2018/illinois/st-clair-county