Overview
Appalachian Power plans to construct approximately two miles of 138-kilovolt (kV) transmission line and a new electric station near a growing load center in southern Botetourt County. The transmission line and distribution station are needed to reliably serve nearby Botetourt County customers. The line will be constructed using single-pole steel structures. Planning and siting will take place in 2007. Engineering, surveying and right-of-way acquisition will take place in 2008. Construction is slated to start January 2009, with an in-service date of June 2009. The total project is estimated to cost about $8 million.
Why are these new facilities needed?
The Lake Forest Project is needed to maintain reliable electric service for nearby Botetourt County customers. Currently, customers in this area are served by 138 kV transmission stations located in Bonsack and Cloverdale and one 34.5 kV station at Blue Ridge. Due to growth in electric demand in the southern Botetourt and eastern Roanoke County areas, some of the electric equipment serving the area is expected to be beyond its rated loading capacity by summer 2008. Adding the new project allows Appalachian Power to balance the customer load among three key 138 kV substations, rather than the two now serving the area. More importantly, it provides switching capabilities to find alternate feeds for customers when an outage does occur.
Are there other facilities that are part of this project beyond the station and line? Appalachian will use existing pole lines to convert the single-phase service to three-phase service between Rt. 220 and Rt. 460., along Mountain Pass Road and the northern end of Laymantown Road. In addition, there are upgrades planned to the 12 kV system along Rt. 460 west of Blue Ridge Station. This enhancement will improve reliability of all customers served by Blue Ridge Station.
How many customers are served by these overloaded facilities?
Approximately 7,100 customers in Botetourt and Roanoke counties are in the area that will be reinforced with the new project.
How will these facilities increase electric reliability?
The new line and station will prevent overloads of critical electric facilities and provide adequate capacity levels for future growth and development in the area. Without this construction, electric demand will outpace the electric infrastructure jeopardizing the reliability of electric service for customers in the area. Specifically, the line and station will:
- Improve the reliability of service for customers in Botetourt County by reducing the length and thus the exposure of the distribution lines.
- Provide alternate ways to serve customers during power outages.
- Alleviate thermal overload conditions at the Bonsack Station, which can cause power outages.
- Allow scheduled station maintenance without interrupting service to customers in the area.
Have there been any problems with reliability?
Due to the number of customers fed from these circuits, the outage frequency and duration for customers in the area is higher than normal when compared to other Appalachian Power customers. In normal circumstances, when a power outage occurs the company can often isolate the location of the outage and find alternate sources of electricity for customers. That is not the case in this area. For example, in the last three years, customers in this area have experienced more than 10 outages that could have been shortened had the company had an alternate source of 138 kV power supply.
How will the line route be chosen?
Appalachian Power has developed preliminary 500-foot-wide proposed corridors for the Lake Forest Project. These preliminary corridors will be reviewed by the public, local government, and state and federal agencies. Ultimately, the company will develop a preferred 500-foot wide corridor (or corridors), and a preferred 100-foot wide right of way within that corridor and take that to its regulators, the Virginia State Corporation Commission. Throughout the state process, and by working with property owners, Appalachian will identify the best 100-foot-wide right of way for the power line.
What kind of structures will the line use?
The line will be built using weathered single steel poles, rust in color and ranging from 70 to 120 feet tall. The average pole height will be 100 feet tall.
What is the timeline for the line?
Right of way acquisition and line design are scheduled for 2008. Right of way clearing and construction of the line is expected to begin in January 2009, and the line is scheduled to be complete by the end of June 2009.
How much will the line cost?
We estimate the total project will cost approximately $8 million.
How much right of way is needed for a 138kV line?
Typically a 138kV line needs 100 feet of right of way.
What will be the environmental impact of this line?
A 138kV line requires a relatively small footprint. Therefore, the disturbance caused by the project will be limited to moderate tree removal and other line-clearing activities.
Are there any alternatives to building this line?
The last major reinforcement to the 138 kV system in this area came in 1989 when the Bonsack Station was put in service. In the years since, Appalachian has made incremental improvements. Before proposing the Lake Forest Project the company evaluated other options including increasing transformer sizes at existing stations, transferring loads to other areas, adding circuits to existing stations, for example. In the end, none of the alternatives provided the increased reliability compared to the Lake Forest Project.
Can the line be built underground?
Appalachian Power does not support the practice of putting electric transmission lines underground, except when extenuating circumstances exist, and then, only for a short distance. Building transmission lines under ground cause problems and delayed repairs when equipment fails. With overhead facilities, crews can see problems, assess problems and make repairs quickly. When equipment is buried the response time, and in turn the reliability of the equipment suffer. In addition to being less reliable than overhead power lines, underground facilities are much more expensive to build, costing two or three times more than overhead construction. In some cases the cost can be 10 times more. Utility commissions typically only allow utilities to recoup costs of overhead construction.
Are there health risks from exposure to magnetic fields near high voltage power lines? All electrical equipment carrying a current generates electric and magnetic fields (EMF). This pertains as much to the electrical appliances in our homes as it does to power lines, power stations and their related equipment. Questions have been raised over the past 20 years about a possible link between exposure to EMF and certain kinds of health effects. While numerous studies have been conducted, as a body of work they have failed to link EMF to specific health effects. More recent studies have cast further doubt on the hypothesized link.
Lake Forest Information
