About oil and gas in Illinois

Oil and gas facts

Illinois has 23,402 oil and gas production wells, 6,535 Class II injection wells, and 1,078 gas storage wells in Illinois. Furthermore, there are 3,991 production and injection wells in the Plugging and Restoration Fund.
These wells are controlled by 1,135 operators.
Oil production occurs in 40 of Illinois' 102 counties. Most of the production is located in the southern part of the state.
The oil-producing region of Illinois is part of a geologic structure or province known as the Illinois Basin. The basin covers southern Illinois, western Kentucky and western Indiana.
Between 2015 and 2023, an average of 435 drilling permits for oil, gas and injection wells were issued per year.
The IDNR Office of Oil and Gas Resource Management conducts about 30,000 inspections each year and initiates about 3,000 enforcement actions annually.
Most wells in Illinois are stripper wells with a daily production of 1.5 barrels per day.

The first attempt at drilling oil wells in Illinois occurred in 1853 near Champaign. These wells produced "swamp gas" or "drift gas" from glacial till but no oil.
Since 1853, about 155,000 oil, gas and injection wells have been drilled in Illinois.
The first oil wells were drilled in Clark and Montgomery counties in the early 1860s.
Commercial oil production began in Illinois in 1905. That year, 181,000 barrels of oil were produced.
Most oil produced in Illinois between 1894 and 1937 came from shallow zones (formations less than 1,000 feet). In 1937 deeper zones were discovered (formations between 2,500 and 3,500 feet).
The deepest well ever drilled in Illinois was more than 13,000 feet deep.
The State of Illinois has had a program regulating the oil and gas industry since 1939.