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Nicor's History

Celebrating 60 Years

In the early 1950s, excess summertime supplies were diverted into limited storage facilities or sold for low priority uses. While northern Illinois doesn’t have sandy beaches our mountain views, what it does have are vast underground sandstone formations, which proved to be perfect for storing natural gas.

By 1958, company engineers and geologists discovered an underground dome-shaped reservoir or “aquifer” near Troy Grove in LaSalle County. Taking full advantage of this geography, Nicor Gas established its first storage field which revolutionized the company’s storage capabilities.

Today, Nicor Gas has eight underground storage facilities that, combined, have about 150 billion cubic feet of annual storage capacity. However, as Nicor Gas’ largest storage facility, Troy Grove accounts for approximately one-third of that. It’s estimated that the facility has enough natural gas in storage to manage the heating needs of residential customers in Mendota for the next 148 years.

Troy Grove is also home to Nicor Gas’ Fire School, where natural gas fire training is given to firefighters throughout its northern Illinois service territory. The 10-acre site has more than a dozen unique scenarios designed to test and expand participants' knowledge on how to effectively and safely extinguish natural gas-fueled fires.

During the training, which is provided at no cost to participating departments, firefighters can test the use of water and dry chemicals, used separately and together, to extinguish natural gas and various other types of fires. The training is hosted in conjunction with the Illinois Fire Services Institute.

The fire school is not only offered to first responders in the communities served by Nicor Gas, but also to its employees, from field operations to human resources. Our safety training, operating standards and around-the-clock monitoring meet and exceed all state and federal regulations. That’s because nothing is more important than the safety of our customers and our communities.

Keeping Gas Prices Down
Nicor Gas customers are connected to a 34,000-mile distribution system that is part of a network of eight interstate pipelines. We purchase gas during the summer months when it is normally less expensive and store it for use throughout the year. This helps keep winter costs down and our year-round supply up. Our gas purchasing strategies, coupled with our underground storage facilities, ensure that Nicor Gas customers receive reliable, competitively-priced service.

Regional Offices
Our corporate office is in Naperville, Illinois, with regional offices located throughout our service territory





Nicor Gas is a direct descendant of Ottawa Gas Light and Coke Company, the company that
lit up the historic Lincoln-Douglas debate in Ottawa on Aug. 21, 1858. 


More than 70 gas companies eventually merge into three, including the Illinois Northern Utilities Company.

1950 - 1953  

Illinois Northern Utilities Company becomes part of Public Service, and Public Service merges into Commonwealth Edison.


Com Ed cuts ties with its gas properties. Northern Illinois Gas is formed from several companies in and around Ottawa.

Mid 1950s

In 1955 Union Gas and Electric is acquired. Several years later, the groundwork is laid for the world's largest underground gas storage system.


We expand our service area and begin drilling for natural gas. We also increase our natural gas storage capacity by developing underground storage.


Northern Illinois Gas begins operating its natural gas business as Nicor Gas.


Nicor Gas becomes a subsidiary of AGL Resources Inc., an Atlanta-based energy holding company.

July 2016

AGL Resources becomes Southern Company Gas, a wholly-owned subsidiary of Southern Company.


As part of the Southern Company Gas family, we continue to deliver safe and reliable natural gas.