County annual report · FIPS 04019
2018 Pima County, AZ Power Outage Report
In 2018, customers in Pima County, AZ went without power for an average of 0.7 hours, a total of 325K customer-hours (Arizona average 1.9 hours). That ranks 10th worst of 13 Arizona counties and 2444th of 2,798 nationally.
Compared with AZ, the US and 2017
Coverage line is EAGLE-I's share of Arizona customers tracked each year.
Biggest outages in Pima 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 | July 27, 2018 15:00 | July 28, 2018 17:00 | 1d 2h | 12,332 | 23K |
| 2 | January 15, 2018 13:30 | January 15, 2018 13:45 | 15m | 6,427 | 1,607 |
| 3 | August 7, 2018 18:15 | August 8, 2018 04:15 | 10h | 6,148 | 32K |
| 4 | May 29, 2018 21:15 | May 29, 2018 23:15 | 2h | 6,072 | 6,100 |
| 5 | February 20, 2018 06:30 | February 20, 2018 07:45 | 1h 15m | 6,065 | 7,512 |
| 6 | January 25, 2018 03:30 | January 25, 2018 04:00 | 30m | 6,063 | 3,032 |
| 7 | July 5, 2018 21:00 | July 6, 2018 02:45 | 5h 45m | 5,921 | 7,099 |
| 8 | June 16, 2018 05:45 | June 18, 2018 02:30 | 1d 20h | 5,128 | 16K |
| 9 | February 28, 2018 11:15 | February 28, 2018 19:15 | 8h | 4,607 | 4,426 |
| 10 | November 13, 2018 13:45 | November 14, 2018 13:00 | 23h 15m | 4,515 | 5,520 |
Outage episodes by size in 2018: 168 reached 100+ customers, 76 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 Pima 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 |
|---|---|---|---|---|---|
| Arizona Public Service Co | 2018 | 2.6 hrs | 1.08 | 86 min | 0.84 |
| Sulphur Springs Valley E C Inc | 2018 | 73 min | 0.93 | 73 min | 0.93 |
| Trico Electric Cooperative Inc | 2018 | 1.5 hrs | 0.66 | 28 min | 0.25 |
| Tucson Electric Power Co | 2018 | 51 min | 0.78 | 0 min | 0.00 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| USBIA-San Carlos Project | - | - | - | - | - |
| Tohono O'Odham Utility Authority | - | - | - | - | - |
| Ajo Improvement Co | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 87% of Arizona's customers in 2018; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 492,744 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. Pima County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Pima County, AZ 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/arizona/pima-county