How We Restore Power

What causes an Outage?

An outage can happen at any moment due to unforeseen circumstances. Any time an outage occurs, our aim is to work quickly and safely to restore power to all customers affected.

Common Causes of Outages

Natural Causes Wind, heavy snow, ice, trees, or branches falling on powerlines.

Human or Animal Error Humans and animals can cause damage to poles and powerlines.

Equipment or Technology Failures Essential equipment, such as feeders, transformers, cables, or switches, sometimes are in need of repair or replacement.

Scheduled Interruptions Periodic maintenance or equipment upgrades.

How does City Light prioritize an outage?

1. Life Safety Crews are dispatched immediately to fix downed powerlines that pose any immediate safety threats to the vicinity.

2. Emergency Services Crews are dispatched to emergency services and facilities critical to public health and safety, such as hospitals, police, and fire.

3. Customers and Residents Crews repair areas that will restore power to the largest number of customers and continue working until all customers are back in service.

What is an Estimated Time of Restoration (ETOR)?

When an outage first occurs, an initial Estimated Time of Restoration (ETOR) is auto populated by our system. An ETOR, is a high-level average based upon the various types of outages (example: overhead lateral fuse vs. overhead transformer failure). Initial ETOR’s are designed to inform customers that we are aware of trouble in their location, and that an ETOR has been established and will be updated as the situation progresses. Many factors drive actual restoration times, these include access, weather, assessment of the exact cause, securing the resources, hardware, and equipment needed, and personnel mobilization.

Any ETOR changes that are made after the initial estimate are done by our operations staff. These are based on any available information they have at that time. The more information we have - such as location (address or at least close proximity) or cause (car has collided with a pole) - the better we can estimate the time needed to make the necessary repairs. However, there are times when we don’t have enough information and need to rely on our line service crews out in the field to investigate further.

Our hope is always to get as many customers’ power restored as quickly as possible, but there are times when additional staff, specialized teams, or multiple repairs are needed before we can fully restore an outage. At all times, the safety of our crews is our utmost priority. We will never endanger personnel for expediency.

How does City Light restore power?

City Light crews begin the process of power restoration with safety top of mind. They begin by first ensuring that power lines do not pose a threat to themselves or others. Then, working systematically they begin restoring power as quickly and efficiently as possible. Bear in mind, if adverse conditions are present such as high winds or icy roadway, this may delay crews from being able to successfully access equipment.

Transmission Towers Crews begin repairing any damage that may be present at the largest source of power, our high-voltage transmission lines that carry power to our substations throughout our service territory.

Substations As junctions for transmission lines meant to maintain reliability of power, when there is a malfunction in a switch, we quickly repair this with the least amount of disruption by isolating the problem.

Feeder Lines Feeder lines bring power into neighborhoods and business districts. Power is then distributed by local lateral lines. We quickly repair these lines to restore service to the largest number of customers in the least amount of time by isolating the source of the outage.

Lateral Lines If a neighbor has power and you don't, there may be damage to lateral lines that feed power to your home and not your neighbors. If the line that carries power from the lateral to your home meter is damaged, we will find the source and repair it as quickly as possible.

How does City Light prevent outages?

Keeping Trees Trimmed Keeping vegetation trimmed where needed to reduce the risk of electrical fires and injuries from downed powerlines. Every day, our team of professional arborists works to ensure the reliability of our electricity and safety of our communities, while protecting the health of our urban forest. Learn more about our approach to vegetation management.

Ensuring the Safety and Reliability of Our Service In addition to repairing downed powerlines and maintaining grid infrastructure, we’re always working to improve safety and reliability through streetlight repair and other safety programs across the region. Learn more about the ongoing work we’re doing to keep you safe and the power on.

Applying Advanced Grid Analytics Grid analytics and advanced metering technology provide us with critical data about equipment, power quality, voltage regularity, and more. This data helps us better anticipate a possible outage and fix it before it becomes an issue.