Interstate 69 in Indiana
The original plan (in a DEIS prepared by INDOT in 2004, but later dropped) was for I-69 to leave the now-former I-164 alignment somewhere just east of Green River Road (exit 3) and head south (instead of turning west with I-164) for approximately before crossing the Ohio at a point near the mouth of the Green River. This portion of the route had not then been funded, as construction of the new Ohio River crossing and its approaches in both states was expected to cost approximately $800 million. Indiana and Kentucky officials had said construction on the new Ohio River Bridge would not begin until at least 2020, after two new crossings near Louisville were completed. With Indiana then preparing to break ground on SIU 3, Kentucky officials indicated that collecting tolls might be the only feasible option for completing the I-69 bridge, as traditional federal and state funding for such projects were drying up. , neither Kentucky nor Indiana officials had yet come up with the money to plan and construct this I-69 bridge.
Interstate 69 in Michigan
A discontinuous section of M-78 freeway east of Flint was completed in 1969. The same year, I-475 was named the David Dunbar Buick Freeway, after the founder of Buick Motor Company in Flint; the same legislation, House Concurrent Resolution 22 of 1969 named the M-78 freeway through Flint for Louis Chevrolet. In 1970, the I-496 freeway was completed and the Bus. M-78 designation was removed through Lansing. A freeway segment between Flint and Lapeer opened in 1971. M-21 was routed down M-13 to the new freeway where it joined the M-78 designation from M-13 east. The section of M-21 formerly between M-13 and Bus. M-54 was redesignated M-56. The M-78 designation was replaced by I-69 in 1973 after a Temporary I-69 (Temp. I-69) designation was extended northward from Charlotte through Lansing to Perry. On September 4 of that year, I-69's designation was officially extended by Congress to end at I-475 on the east side of Flint; this extension, and all subsequent ones, was of "non-chargeable mileage", or segments not financed through the Interstate Highway fund.
In 1980, a Flint-area politician wanted to dedicate a highway after the United Auto Workers (UAW). As a result, the David Dunbar Buick Freeway name was moved off I-475 and applied to I-69 in Flint. The American Association of State Highway and Transportation Officials (AASHTO) approved the extension of the I-69 designation eastward in 1983 so that it would terminate at the international boundary at Port Huron; this approval was contingent on construction of the roadway to Interstate Highway standards and other appropriate approvals at the federal government level. The remaining segment of freeway connecting Lapeer with Wadhams opened in 1984 as I-69 and several additional changes were made to the highway system at the same time. M-21 was shortened to Flint and replaced M-56 through the city. The former route of M-21 in Port Huron became BL I-69, and the remainder of that highway was turned back to local control. The I-69 designation was officially extended once more under Congressional legislation on February 10, 1987; this last extension designated I-69 all the way to I-94 in Port Huron to reflect the 1984 openings.