Air Lake Empire Frequently Asked Questions

What is being proposed?

There are three parts to the proposed project: a substation, a re-built transmission line and a new transmission line.

Here are more details of the project:

Who is proposing the transmission line?

Great River Energy and Xcel Energy are proposing a transmission line that would connect Dakota Electric Association’s new proposed substation from the east and west. Great River Energy’s line would run from the Empire Substation (east of Farmington) to the new substation. Xcel Energy’s line would run from their Air Lake substation (west of Farmington) to the new substation.

Why is this project needed?

The substation and transmission lines are needed to ensure reliability in the growing area. The existing 69kV transmission system is becoming overloaded. Farmington residents would benefit from this improved reliability. The facilities are being shared by utilities in order to keep costs down.

What is the timeline for the project?

A route permit application was submitted to the Minnesota Environmental Quality Board (EQB) in March, 2004. A public information meeting was held on March 30, 2004 in Farmington.

On May 7, 2004, the EQB chair accepted the application as substantially complete.

The EQB conducted a public information meeting on June 24, 2004 at the Dakota County Extension Office.

Upon approval of the permit application, engineering work and easement acquisition will occur January to August 2005 and construction is slated for fall 2005 to spring of 2006.

See map included on the project fact sheet.

Why did you choose this route?

Routes are considered based on a variety of considerations such as social (proximity to residences, structures, businesses and public facilities), environmental (woodland, wetlands, stream and lake buffers) and engineering (existing rights-of-way, minimize large structures, constructability and maintainability).

Proposed transmission lines longer than 10 miles also require a certificate of need from the Minnesota Public Utilities Commission.

Can I view the presentation I saw at the public meetings?

Here’s a copy of the presentation.

Copies of the application and other relevant documents are publicly available at the EQB website.

What type of transmission structures will be used?

The transmission structures used for this project will be determined by the characteristics of the final route, including terrain and existing infrastructure. The appearance of individual structures will vary with the final route and design but in general the structures will be a single wood pole with horizontal insulators. Some locations may require larger steel poles.

There are three different types of transmission towers that could be used in the project. Here's a comparison of a possible new transmission line with an existing one.

Although we try to keep construction damage to a minimum, some may occur. Any damage will be repaired.

Constructing long-distance, high-voltage transmission lines underground is feasible but not practical because of electrical losses, reliability and cost factors. Locating and repairing line failures also takes longer on underground systems. The reactive losses of the cable are substantially higher than overhead lines. Installation requires lengthy disruptive construction techniques. Design concerns such as ampacity and heat dissipation are frequent limitations. Underground systems are justified primarily in heavily populated downtown urban centers, where right-of-way is severely limited for overhead lines.

Will the new line cause radio or television interference?

Radio or TV interference is a function of the signal strength and transmission line induced noise. Noise with respect to interference is typically caused by loose hardware on the pole. This is easily corrected by tightening the loose part.

Will the new line be safe?

Every effort is made to ensure safety in construction, operation and maintenance of transmission lines. Great River Energy's practices meet or exceed standards set by recognized electric national safety codes and safety codes adopted by local governing units. Lines and line structures are designed to withstand extreme weather conditions. Protective devices at the source of the lines stop the flow of electricity under abnormal operating conditions.

What about EMF?

Electric and magnetic fields (EMF) are created by any wire conducting electricity, including transmission lines, household appliances and business equipment. These fields are strongest close to the source (wires) and rapidly diminish as you move away from the source. EMF levels from transmission lines diminish rapidly with distance.

EMF is a function of the amount of current or amps that flow on the line, and therefore EMF varies hour to hour. With the same circumstances the EMF levels from the new 115 kV line will be about two-thirds that of the existing 69 kV line.

For more information about EMF, contact the Environmental Health Division, Minnesota Dept. of Health at 651-215-0699 or visit their EMF website. The National Institute of Environmental Health Sciences provides another helpful website.

List of additional EMF resources

Where can I go for more information?

Please call Dale Aukee at Great River Energy, 763-241-2229, if you have more specific questions about this transmission project.