The City of Manassas is planning a reliability assessment of its electric system following recent outages and three years in which equipment failure remained the largest reported outage category.
The review comes as three City reliability measures finished slightly outside their stated targets in 2025. Equipment failure accounted for 58 of 131 reported outages that year, while the City is also spending $3.465 million on substation maintenance and improvements.
The assessment is expected to cost about $25,000 and take eight to 12 weeks. Public materials do not yet identify when it will begin, what parts of the system it will examine or when it will be completed.
2-Minute Brief
WHAT’S HAPPENING: The City of Manassas is planning an assessment of the condition and reliability of its electric system.
WHY IT MATTERS: Equipment failure has been the largest single reported outage category for three consecutive years, and three reliability measures finished slightly outside City targets in 2025.
WHAT THE CITY IS DOING: The City has $3.465 million programmed for substation maintenance and improvements and also addresses vegetation and animal contact through tree trimming and animal-protection measures.
RECENT OUTAGE: A City outage map showed about 2,090 customers affected across two areas on Sept. 17 at one point. The final cause, customer count and restoration time have not been publicly identified.
WHAT’S NEXT: The planned reliability assessment is expected to take eight to 12 weeks. Its detailed scope, start date and completion date have not yet been made public.
What the Outage Records Show
City of Manassas operating reports show equipment failure was the largest single reported outage category for three consecutive years:
| Year | Total reported outages | Equipment-failure outages |
|---|---|---|
| 2023 | 142 | 63 |
| 2024 | 151 | 58 |
| 2025 | 131 | 58 |
Equipment failure accounted for about 44% of reported outages in 2023, 38% in 2024 and 44% in 2025.
Other outages came from causes outside that category. City planning documents specifically address vegetation and animal contact through regular tree trimming and animal-protection equipment on parts of the overhead system.
The annual reports do not show which equipment failed, how old it was or whether failures were concentrated on particular circuits or substations.
How the City Measures Reliability
The City tracks several measures showing how often customers lose power and how long interruptions last.
For 2025, the City’s System Average Interruption Duration Index, or SAIDI, was 56.939 minutes. That means the average customer experienced about 57 minutes of sustained power interruptions during the year, about five minutes above the City’s target of less than 52 minutes.
Service availability was 99.989%, compared with a target of 99.99%, a difference of 0.001 percentage points.
For customers who experienced a sustained interruption, average restoration time was 167.611 minutes, or about two hours and 48 minutes. That was about 12 minutes longer than the City’s target of less than 156 minutes, or two hours and 36 minutes.
All three measures were slightly outside the City’s stated targets. They measure different parts of reliability and do not, by themselves, explain why outages occurred.
Maintenance and Capital Work
The City of Manassas capital plan lists $3.465 million for Substation Maintenance and Improvements.
The program covers work at City-owned distribution substations, facilities that reduce higher-voltage electricity to levels that can be distributed through the local system.
The work includes transformer maintenance; replacement of voltage regulators, which help keep electricity flowing at a steady voltage; battery maintenance; lightning protection; and possible capacity improvements.
The program is funded through the City Electric Fund and supports infrastructure already serving the municipal electric system.
The City of Manassas owns its local electric distribution system, while much of the electricity delivered to customers is purchased through the Virginia Municipal Electric Association, which obtains power through a larger system connected to Dominion Energy and PJM Interconnection. The Journal’s earlier reporting on Manassas utility bills explains how local electric rates and the Power Cost Adjustment can affect what customers ultimately pay.
The Planned Reliability Assessment
Utility Commission records describe an asset-management and reliability assessment expected to take approximately eight to 12 weeks and cost about $25,000.
Public materials do not yet identify when the work will begin, its expected completion date or exactly which equipment, circuits or substations will be examined.
The City has also not yet detailed what recommendations or final report are expected from the review.
The Sept. 17 Outage
A City of Manassas outage map captured Sept. 17 showed two outage areas beginning around 9:24 p.m., with about 1,600 customers affected in one area and 490 in another at that time.
The map did not identify the cause. The Manassas Journal found no subsequent City public report establishing the final number of customers affected, the cause or the restoration time.
The Journal has asked the City for those details.
Existing System and New Customer Infrastructure
The City of Manassas is also expanding electric infrastructure to serve new development and large business customers.
One example is the dedicated AWS/BCG substation. Earlier City capital plans placed that project at approximately $43.7 million. City documents state that construction costs for the dedicated substation are to be paid directly by the developer.
That differs from the City’s $3.465 million Substation Maintenance and Improvements program, which is funded through the Electric Fund and supports the existing municipal electric system.
Sources / Reference Links
- City of Manassas Utility Commission packet, January 8, 2026, including December 2025 outage and reliability reports
- City of Manassas Utility Commission packet, February 2026 electric operating report
- City of Manassas Utility Commission meeting materials, Aug. 13 and Sept. 10, 2026
- City of Manassas capital plan, Substation Maintenance and Improvements program
- City of Manassas capital planning documents, AWS/BCG substation
- City of Manassas Comprehensive Plan, electric-system tree trimming and animal-protection measures
- Manassas Journal: Manassas Utility Commission to Review AWS Substation Delay, Electric Rates and System Reliability
- Manassas Journal: Utility Bills Spike: Higher Rates Hit Manassas Households Across the Board
- Manassas Journal: PJM Takes Emergency Action as September Heat Strains Regional Power Grid
