Beginning on the effective date of this Act, the Fourth Judicial District consists of the counties of Jo Daviess, Stephenson, Carroll, Ogle, Lee, Winnebago, Boone, Mercer, Rock Island, Whiteside, Henry, Stark, Putnam, Marshall, Peoria, Tazewell, Adams, Pike, Calhoun, Schuyler, Brown, Cass, Mason, Menard, Morgan, Scott, Greene, Jersey, Macoupin, Sangamon, Logan, McLean, Woodford, Livingston, Ford, Henderson, Warren, Knox, Fulton, McDonough and Hancock.