American Transmission Co.

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Blog | American Transmission Co. - Part 40

Why do power lines sag on hot days?

SaggingSpan_cropIn hot weather, power lines can overheat just as people and animals do. The lines are often heavily loaded because of increased power consumption, and the conductors, which are generally made of copper or aluminum, expand when heated. That expansion increases the slack between transmission line structures, causing them to sag.

Transmission lines are designed to meet the requirements of state electrical codes. State codes provide minimum distances between wires, poles, the ground and buildings. Industry standards are often more strict and are incorporated in transmission line design, construction and maintenance. As a precaution, no one should be on an object or in contact with an object taller than 15 to 17 feet while under a high-voltage line.

ATC Interns dig in for Day of Action to support United Way

ATC interns enjoyed giving back to the community at Green Power Garden in Waukesha, Wis.

ATC interns enjoyed giving back to the community at Green Power Garden in Waukesha, Wis.

Interns from American Transmission Co. joined 700 others for an Intern Day of Action to benefit the United Way of Greater Milwaukee & Waukesha County. Forty ATC interns volunteered to help with garden maintenance, picking and planting at Green Power Garden. The garden primarily provides fresh vegetables and fruit to guests of the Hope Center, an organization that serves people in need in Waukesha County, Wis., sharing surplus harvest with the Food Pantry of Waukesha.

Here is what our interns had to say about the experience:

“Participating in the Intern Day of Action was a rewarding experience … It brought us all together, and for a great cause!  I am proud to have Lived United … and to know that what we did will help to make a difference once the produce is harvested in autumn.” – Whitney C., project engineering intern

“The Intern Day of Action was a great way to connect with the community through ATC. It was wonderful to see the impact we made at the end of the day and to know that we were helping people in need.  Being a part of ATC’s presence in the community was a very fun and rewarding experience.” – Eden W., EMS intern

“I’d say that the best part about it was being able to get some time outside the office to really feel like we were making a difference … It also felt like a very unique way to give back to the community which made me enjoy it personally.” – Noah F., information management analyst intern

The Intern Day of Action was a great opportunity for our employees to help support the United Way.

ATC, MJ Electric collaborate on donation to Heritage Hill State Park

MJ crew setting pole at HHOld Glory is flying proudly over the refurbished Fort Howard area of Heritage Hill State Park in Green Bay this summer, thanks in part to the efforts of American Transmission Co. and our construction partner, M.J. Electric.

Earlier this year, park managers asked if we could provide a transmission structure from one of our construction projects to use as a flag pole on the park grounds. We provided a cedar pole from a transmission line rebuilding project near Shawano, and M.J. Electric furnished a crew and the equipment to set the pole in June.

A flag raising was one of many events during the grand opening weekend of a $2.1 million addition to the Fort Howard display.

Heritage Hill is a living history museum dedicated to preservation of buildings and artifacts as well as the interpretation of history on northeastern Wisconsin. It contains 24 original and reproduction buildings from 1672 to 1940.

PowerForward: A changing utility landscape

ATC was created to resolve a number of electric reliability problems caused, in part, by the operation of a balkanized transmission system. In 2001, when we combined the transmission assets of our owners, the local distribution companies, we began to link the assets together to create a much larger, more robust interconnected system. While many of those “seams” issues between the individual utilities have been addressed in recent years, we continue to face a changing landscape in our planning and operations. Public policy changes — including new air quality rules that result in the retirement of old generators and construction of new, cleaner facilities, as well as renewable energy mandates — influence how we plan and operate our system. A competitive energy marketplace introduced in the region in 2005 also affects our plans and system design.

Learn more about the continuing need for reliable, affordable and environmentally responsible electricity at

ATC ranked number 4 on the Milwaukee Journal Sentinel’s Top Workplaces list

It’s exciting times at American Transmission Co. ATC has once again been selected as a 2015 Top Workplace in southeastern Wisconsin by the Milwaukee Journal Sentinel.


Managers had fun thanking employees with delicious ice cream treats.

The top workplaces are determined based on feedback from an employee survey, conducted by WorkplaceDynamics, LLP, an organizational health and employee engagement research firm. This is the sixth year the Milwaukee Journal Sentinel has worked with Workplace Dynamics, LLP to develop and publish the list of top 150 area workplaces, and it’s the third time ATC has been named to the list. This year, ATC is number 4 on the list of midsize companies, up from its number 12 position last year.

Approximately 80 percent of ATC’s Milwaukee-area employees responded to the survey, which asked questions about ATC’s values, execution, leadership, culture, job satisfaction and overall feelings about working at the company.

Last fall, ATC also ranked among the nation’s top-25 medium-sized Great Places to Work as published in FORTUNE magazine.

Click here for the entire list and here for ATC’s company profile.