When it comes to power distribution for homes and businesses, there are two main options for service feeders – underground and overhead. Both have advantages and disadvantages that determine which is the better choice depending on the situation. This article will examine the differences between underground and overhead service feeders to help understand when each one is preferable.

What are Service Feeders

Service feeders are the final leg of electricity delivery that connects the main power lines from the utility company to the consumer’s home or building. They carry electricity at voltages below 600 volts to power a residence or business.

Service feeders can either run overhead, mounted on poles and power lines above ground, or underground, through buried cables and conduits under the surface. The feeder line runs from the transformer on the pole to the meter and electrical panel of the building being served.

Choosing between underground and overhead service feeders depends on several factors:

Cost Differences

One of the biggest considerations when choosing between underground and overhead service feeders is cost. Installing underground service lines costs significantly more than overhead in most cases:

Overhead feeders: Attaching wires to utility poles is the most affordable option for most residential connections. Overhead installation costs range from $1,500-$5,000 on average.
Underground feeders: Burying utility lines underground ranges from $5,000 for a basic residential hookup to over $20,000 for a long line. Materials and labor for excavation make underground more expensive.

Overhead service is generally the most economical choice for standard residential connections. However, for commercial buildings and upscale housing developments, the visual appeal of buried lines often makes underground service the preferred choice, despite the higher costs.

Aesthetic Differences

One of the biggest differences between overhead and underground service feeders is appearance:

Overhead feeders involve wires strung between utility poles. This can clutter the view with criss-crossing lines and poles along the streets and over buildings.
Underground feeders keep utility lines buried and out of sight for a cleaner look. No above ground wires or obstructive poles are necessary.

Burying utility lines improves curb appeal and aesthetics especially in higher end communities or commercial areas. Although more expensive, many homeowners and business owners consider the visual improvement worth the added cost.

Reliability Factors

Reliability is another key difference between overhead and underground service feeders:

Overhead – More exposed to weather events like wind, ice, snow, and storms. Trees, animals, accidents and other threats can potentially disrupt overhead lines.
Underground – Buried power lines are more protected from weather events and outside forces. Underground service is generally more reliable.

According to data from the Energy Information Administration, underground lines experience around 1.5 outages per year on average compared to 2.5 outages annually for overhead lines. Faults and disruptions are more common with overhead feeders.

However, when outages do occur, repairs take longer for underground service. The process of locating, accessing and fixing buried line issues is more complex than repairing overhead wires.

Maintenance Considerations

Overhead and underground service feeders also differ in terms of maintenance:

Overhead – Easier to inspect visually and perform repairs. Costs are lower for ongoing maintenance.
Underground – More difficult to monitor buried lines. Excavation is required for periodic maintenance and repairs at greater expense.

The visibility of overhead lines allows for easier regular maintenance checks. Issues can be spotted through visual inspections and repairs completed without digging. In contrast, maintenance of buried power lines requires underground cable locating, excavation, and greater manpower for a single repair.

Installation Factors

Several factors related to the installation process help determine whether overhead or underground service feeders work better:

Overhead – Poles must be installed to carry overhead wires. Requires proper pole spacing, wire heights and following safety codes.
Underground – Trenching or boring is needed to bury conduits and cables. Underground hazards like rocks must be avoided. Restoration of surfaces and landscaping adds costs.
Pre-existing infrastructure – If poles and overhead lines are already present from the utility provider, overhead service is simpler to add. Lacking underground infrastructure makes underground feeders more complex and disruptive to install.
Geography – Boring underground lines is more difficult in areas with hard bedrock close to the surface. Overhead lines may be better suited.

The specifics of the setting and what previous utility infrastructure exists impact whether overhead or underground installation is more feasible. Both options have their own unique process and equipment requirements.

Safety Factors

Another consideration when choosing between overhead vs. underground service feeders is safety:

Overhead – Energized lines located high off the ground are largely out of reach. But risks include falling poles/wires during storms. Proper height clearances must be maintained.
Underground – Buried lines avoid most electrical risks to people and property above ground. But hitting buried lines when excavating can be dangerous. Electrocutions still occur rarely with underground lines.

Neither option completely eliminates risks. But because overhead lines are exposed and accessible, they tend to cause the most electrical accidents and deaths overall each year. Underground locations reduce exposure to hazards from live wires and equipment for improved safety.

Right-of-Way Issues

Right-of-way needs also differ between overhead and underground service feeders:

Overhead – Lines can cross over most private or public properties. However, regular right-of-way clearance is needed so trees and structures do not interfere with lines.
Underground – No above ground right-of-way is needed. But easements for buried line corridors are required. Space on each property must be made accessible 24/7 for underground facilities.

Overhead lines only need clearance rights for suspended wires, allowing more flexibility crossing properties. Underground lines require perpetual access rights anywhere that buried facilities run, limiting land use more.

Environmental Impact

Another consideration is the environmental impact of overhead vs. underground power lines:

Overhead – More visually disruptive to landscapes. Can interfere with bird and animal habitats on utility poles. Lead to more tree trimming.
Underground – Less visibility leads to less disruption of natural settings. But trenching to bury lines causes temporary ground disturbance during installation.

In general, buried power lines preserve more natural aesthetic by keeping equipment and wires out of view. But underground installation involves heavy machinery and digging that can temporarily disrupt animal ecosystems and vegetation until restoration is completed.

Project Scale Differences

Finally, the size and scale of the electrical service project makes underground or overhead feeders more practical:

Overhead – Often better suited for standard single family homes or small projects. More cost effective and faster to install for small scale needs.
Underground – The expense of underground lines makes this option more practical for large-scale development projects where cost can be spread over multiple buildings and connections.

Although buried lines keep feeders out of view, the considerable added cost usually makes underground service prohibitive for individual residential consumers. But when a housing development involves installing feeders to dozens of units, underground lines become more feasible.

When to Choose Underground Service Feeders

Now that we’ve compared the main differences, in what situations should underground service feeders be chosen over overhead lines?

New Higher-End Homes/Subdivisions

For new construction of premium homes or subdivisions, underground service feeders are often the preferred choice. Although more expensive, the aesthetic appeal of avoiding overhead lines matches the quality of luxury new construction. Homebuyer perception also adds value.

High Property Value Homes

Similarly, for high property value homes, the curb appeal and “upscale” impression from buried utility lines makes underground service feeders a sound investment. Even when retrofitting existing properties, the boosted home value perception makes underground service advantageous.

Scenic/Historic Areas

In locations where maintaining a beautiful landscape or historic ambience is important, such as parks, trails, tourist areas, or historic districts, underground lines are ideal for keeping views unencumbered by overhead wires and poles.

Environmental Motivations

For properties where the owner prioritizes environmental motivations and preserving natural aesthetics, underground service keeps the landscape free of visible utility infrastructure.

Coastal Regions Prone to Storms

In hurricane-prone coastal areas, underground service feeders reduce risks of overhead line disruption and electrical hazards during severe storms when poles can topple.

Areas Where Underground Infrastructure Already Exists

Where underground power infrastructure already exists nearby, extending underground service feeders to additional buildings is preferable for consistency.

Tight Urban Settings

In dense urban environments where space is limited, avoiding above-ground poles and wires helps preserve usable space for buildings, people, parking, etc at ground level.

Service Reliability is Paramount

For properties where maintaining continuous electrical service is crucial – like hospitals, data centers, emergency response facilities – buried lines offer added reliability and protection.

When Overhead Service Feeders Are Preferable

Overhead service feeders also remain a good choice in many situations:

Rural/Remote Regions

For electrifying rural or remote areas where wide utility line spans are needed to cover distances between small populations, overhead service remains the affordable option.

Outlying Residential Buildings

For standalone homes in suburban or semi-rural settings, overhead service from existing utility poles is usually the most economical choice.

Cost-Sensitive Projects

For basic residential service where reducing costs are the highest priority, overhead feeders provide the most affordable solution in most cases.

Sites With Space Limitations

Where lack of space makes underground trenching impractical or impossible, overhead service utilizing existing poles makes sense.

Locations Where Overhead Utilities Already Exist

If above-ground power lines are already in place overhead, matching new service connections to the existing infrastructure avoids redundant buried lines.

Temporary Service Sites

For temporary power at sites like construction projects, festivals, or emergency setups where underground lines would be unnecessary after use, overhead feeders offer versatility.

Areas With Shallow Bedrock

Where shallow bedrock complicates underground boring/digging, overhead service is often better suited as an affordable alternative without excavation obstacles.

Key Takeaways – Choosing Service Feeders

When weighing underground vs. overhead service feeders, there are a few key takeaways to keep in mind:

For most standard residential service, overhead is generally the most economical choice. But underground lines provide added property value.
Higher installation costs for underground lines are offset by better aesthetics and improved reliability.
There is no universally superior option – location specifics and project goals determine the better choice.
New developments trend toward buried lines while individual rural/suburban homes commonly use overhead feeders.
Matching existing infrastructure consistency usually makes sense.

By understanding the costs, benefits, and differences between each type of service feeder, both homeowners and utility providers can make informed decisions on the best option. While overhead lines are prevalent for affordability, underground service offers advantages that make the additional investment worthwhile for the right applications. Carefully weighing the options for a given property ensures the best long-term power distribution solution.

Frequently Asked Questions About Underground vs. Overhead Service Feeders

Underground and overhead service feeders both have pros and cons depending on the situation. Here are answers to some common questions about choosing between them:

Is underground or overhead service more reliable?

Underground service feeders are generally more reliable, with fewer outages from external damage or weather disruption. However, repairs take longer when underground lines do fail. So there is a trade-off to consider between each option’s reliability.

Is it cheaper to install overhead or underground power lines?

Overhead service installation costs significantly less in most cases, averaging $1,500-$5,000. Underground service feeders cost two to five times more on average due to materials and labor involved with trenching and conduit installation.

Can you convert overhead to underground service?

Yes, it is possible to convert existing overhead service feeds to underground lines. However, the extensive construction and costs involved limit conversions to cases where the improvement is worth the substantial investment.

Does underground power lines affect property value?

Underground lines can increase property value, especially for high-end homes where aesthetics matter more. The clean look boosts curb appeal. But added value does not always outweigh the higher installation costs unless preferred by buyers.

Is one type of service feeder safer than the other?

Underground lines reduce electrical risks by keeping energized wires and equipment out of reach. But overhead lines allow for easier inspection and repairs. Neither completely eliminates risks. Underground is perceived as safer overall.

Are permits and inspection required?

Electrical permits and inspection are required for both overhead and underground service feeders to ensure proper code compliance and safety. Underground projects may require additional permits for excavation and restoration.

Who is responsible for repairs and maintenance?

The utility provider is generally responsible for repairs and maintenance on service feeder lines up to the connection at the building. Homeowners must maintain electrical infrastructure on their side.

What determines the type of feeder used?

Factors like costs, aesthetics, existing infrastructure, project scale, geography, tree/landscaping impact, and continuity with other lines in the area are considered when determining whether underground or overhead feeders are better suited to a site.

Can overhead lines be converted to underground?

Overhead power and service lines can be converted to underground lines, but the complex process is very expensive. Unless existing overhead lines obstruct new construction, converting is usually not pursued solely for aesthetic reasons due to the high costs.

Does underground service preclude above ground meters and boxes?

Even with underground service feeders, external meter boxes, transformer boxes, and other equipment may still be visible on building exteriors. Only the main distribution lines are buried, while some connections remain above ground.

Conclusion

Underground and overhead service feeders both have key advantages contingent on the application. While overhead lines are cost-effective and common for standard residential connections, underground feeders provide added value and reliability that makes the extra investment worthwhile for particular projects. Carefully weighing all factors allows the most ideal service installation solution to be determined based on the scenario. With proper planning, either underground or overhead feeders can effectively and safely deliver power to homes and businesses.