Editing Interstate 24 (section)

==History==
A controlled-access highway between Nashville and Chattanooga was first included in the National Interregional Highway Committee's 1944 report, titled ''Interregional Highways'', and a subsequent 1947 plan produced by the Public Roads Administration of the now-defunct [[Federal Works Agency]].<ref>{{cite web |last=Weingroff |first=Richard F. |title=Designating the Urban Interstates |url=https://www.fhwa.dot.gov/infrastructure/fairbank.cfm |publisher=Federal Highway Administration |access-date=August 5, 2018}}</ref><ref>{{cite map |url = http://commons.wikimedia.org/wiki/File:Interstate_Highway_plan_August_2,_1947_big_text.jpg |title = National System of Interstate Highways |author = [[Public Roads Administration]] |scale = Scale not given |location = Washington, DC |publisher = Public Roads Administration |date = August 2, 1947 |access-date = September 4, 2010 |via = [[Wikimedia Commons]] }}</ref>
The route was subsequently part of the original {{convert|1,047.6|mi|km}} of Interstate Highways authorized for Tennessee by the [[Federal-Aid Highway Act of 1956]], commonly known as the Interstate Highway Act.<ref>{{cite book |type = Report |author1 = Tennessee State Highway Department Highway Planning Survey Division |author1-link = Tennessee Department of Transportation |author2 = Bureau of Public Roads |author2-link = Federal Highway Administration |year = 1959 |title = History of the Tennessee Highway Department |url = https://www.tn.gov/content/dam/tn/tdot/documents/100years/History_of_the_TN_Highway_Department.pdf |location = Nashville |publisher = Tennessee State Highway Department |access-date = April 26, 2020 |pages = 51–52 |archive-date = January 23, 2020 |archive-url = https://web.archive.org/web/20200123205613/https://www.tn.gov/content/dam/tn/tdot/documents/100years/History_of_the_TN_Highway_Department.pdf |url-status = live }}</ref> The numbering was approved by the [[American Association of State Highway and Transportation Officials]] (AASHTO) on August 14, 1957.<ref name="AASHO-1957">{{cite map |author = Public Roads Administration |author-link = Public Roads Administration |date = August 14, 1957 |title = Official Route Numbering for the National System of Interstate and Defense Highways as Adopted by the American Association of State Highway Officials |url = https://commons.wikimedia.org/wiki/File:Interstate_Highway_plan_August_14,_1957.jpg |location = Washington, DC |publisher = Public Roads Administration |access-date = June 14, 2018 |via = [[Wikimedia Commons]] }}</ref> While most of the routing of I-24 proved was chosen without difficulty, the mountainous topography of the Chattanooga area posed a challenged to planners. The route was initially slated to pass near 38th Street through the Alton Park and East Lake neighborhoods, but was moved approximately {{convert|1.5|mi|km}} north in August 1955. The route was also planned to pass through a tunnel under Missionary Ridge until October 1960, when planners announced that a {{convert|120|ft|m|adj=on}} deep and {{convert|850|ft|m|adj=on}} wide cut would be made through the ridge.<ref name="Ridge Cut"/> Engineers also initially recommended that the Interstate cross the Tennessee River onto Moccasin Bend south of downtown, and then again cross the river into Lookout Valley a short distance beyond, but this was rejected by the Bureau of Public Roads in April 1958 as too expensive.<ref>{{cite news |title=Bend Road Is Out In View Of Leech |url=https://www.newspapers.com/article/chattanooga-daily-times-bend-road-is-out/136189325/ |access-date=December 3, 2023 |work=Chattanooga Daily Times |date=April 15, 1958 |page=1}}</ref><ref name="Bend"/>

[[File:Nashville, Tennessee 1955 Yellow Book.jpg|thumb|right|1955 Bureau of Public Roads highway plan for Nashville, showing the highway that became I-24 terminating there]]
In 1957, officials in Tennessee, [[Kentucky]], [[Illinois]], and [[Missouri]] began an effort to extend I-24 west of its allocated western terminus in Nashville to [[St. Louis]]; however, each of the states had difficulty reaching an agreement on the proposed routing.<ref name=Kovach1/> Eventually, the debate evolved into two proposed alignments for the extension in Tennessee. The first alignment extended I-24 west of Nashville into Kentucky near Clarksville, and the second would have had I-24 run concurrent with I-40 west of Nashville for about {{Convert|40|mi|km}} to near [[Dickson, Tennessee|Dickson]], before splitting off to the northwest and crossing the [[Kentucky Lake]] impoundment of the Tennessee River a few miles before entering Kentucky.<ref name=Kovach1>{{cite news |last1 = Kovach |first1 = Bill |title = State Fighting Blocks I-24 |url = https://tennessean.newspapers.com/clip/97304204/state-fighting-blocks-i-24/ |access-date = March 10, 2022 |work = The Nashville Tennessean |date = August 11, 1963 |page = 2B |via = [[Newspapers.com]] }}</ref> This latter alignment was favored by many officials in Tennessee and Western Kentucky, but the federal government preferred the former, due to its proximity to [[Fort Campbell]].

On September 17, 1963, the governors of the four states in a meeting with President [[John F. Kennedy]] reached an agreement on the alignment, which included the Nashville-to-Clarksville alignment in Tennessee and extended the route's western terminus to [[Pulleys Mill, Illinois]].<ref>{{cite news |last1 = Laycook |first1 = Lois |title = 4 Governors Agree on I-24; Campbell, Paducah on Route |url = https://tennessean.newspapers.com/clip/97304699/4-governors-agree-on-i-24-campbell/ |access-date = March 10, 2022 |work = The Nashville Tennessean |date = September 18, 1963 |pages = 1, [https://tennessean.newspapers.com/clip/97304735/compromise-i-24-route/ 4] |via = Newspapers.com }}</ref> The four governors also urged the approval of a new east–west Interstate Highway to run between [[Hayti, Missouri]], and [[Jackson, Tennessee]], incorporating a [[Caruthersville Bridge|then-unbuilt bridge]] across the [[Mississippi River]] that had been proposed since the early 1940s.<ref>{{cite news |title = U.S. Offered I-24 Routing |url = https://tennessean.newspapers.com/clip/97304380/us-offered-i-24-routing/ |access-date = March 10, 2022 |work = The Nashville Tennessean |agency = [[Associated Press]] |date = September 29, 1963 |page = 6A |via = Newspapers.com }}</ref> On August 18, 1964, the Bureau of Public Roads, the predecessor agency to the [[Federal Highway Administration]], approved the I-24 extension; however, they only authorized the westernmost {{Convert|27|mi|km}} of the route between Missouri and Tennessee, which was designated as [[Interstate 155 (Missouri–Tennessee)|I-155]] and terminates in [[Dyersburg, Tennessee]].<ref>{{cite news |last1 = Laycook |first1 = Lois |title = U.S. Approves I-24 to Illinois, Bridge in Dyer |url = https://tennessean.newspapers.com/clip/97305134/us-approves-i-24-to-illinois-bridge/ |access-date = March 10, 2022 |work = The Nashville Tennessean |date = August 19, 1964 |pages = 1, [https://tennessean.newspapers.com/clip/97305344/us-approves-i-24-to-illinois/ 2] |via = Newspapers.com }}</ref><ref>{{cite web |url = https://highways.dot.gov/highway-history/interstate-system/50th-anniversary |title = Eisenhower Interstate Highway System, Previous Facts of the Day |author = <!--Not stated--> |date = 2010 |publisher = Federal Highway Administration |access-date = July 5, 2020 |archive-date = August 8, 2020 |archive-url = https://web.archive.org/web/20200808130349/https://www.fhwa.dot.gov/interstate/previousfacts.cfm |url-status = live }}</ref>

[[File:VISUAL POLLUTION ALONG INTERSTATE 24 - NARA - 543878.jpg|thumb|left|Sign for I-24 westbound in [[South Pittsburg, Tennessee]], in September 1972]]
The first section of I-24 to be completed was the section in Chattanooga between SR 58 (Market Street) and east of the railyard overpass, which was let to contract on September 18, 1957, and dedicated and opened on December 23, 1958. This was the first section of freeway in Chattanooga and the first section of Interstate in East Tennessee constructed under the Interstate Highway System.<ref>{{cite news |title = New Road Links Pushed in State |url = https://www.newspapers.com/clip/97301884/new-road-links-pushed-in-state/ |access-date = March 10, 2022 |work = [[The Chattanooga Times]] |date = December 14, 1958 |page = 10 |via = Newspapers.com }}</ref><ref>{{cite news |last1=Gibson |first1=Springer |title=23rd Street Freeway Work Ahead of Schedule |url=https://www.newspapers.com/article/chattanooga-daily-times-23rd-street-free/136183360/ |access-date=December 3, 2023 |work=Chattanooga Daily Times |date=September 4, 1958 |page=3}}</ref><ref>{{cite news |last1=Schneider |first1=Fred |title=Interstate Link On 23rd Opened |url=https://www.newspapers.com/article/chattanooga-daily-times-interstate-link/136182913/ |access-date=December 3, 2023 |work=Chattanooga Daily Times |date=December 24, 1958 |page=3}}</ref> The interchange with I-75, along with the segment of I-75 extending to the Georgia state line, were let to contract on July 26, 1959, and dedicated on May 31, 1961.<ref name=1960report>{{cite book |type = Report |author1 =  |year = 1960 |title = Report of the State Highway Commissioner of Tennessee for the Biennium Ending June 30, 1960 |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3031573&seq=86 |location = Nashville |publisher = Tennessee Department of Highways |access-date = November 12, 2023 |page = 80 |oclc = |via=[[HathiTrust|HathiTrust Digital Library]] }}</ref><ref>{{cite news |author=<!--not stated--> |date=May 30, 1961 |title=Program Is Set At Spring Creek |url=https://www.newspapers.com/clip/119732916/program-is-set-at-spring-creek/ |page=3 |work=The Chattanooga Times |access-date=February 26, 2023 |via=Newspapers.com}}</ref><ref>{{cite news |last=Munck |first=Hal  |date=June 1, 1961 |title=Spring Creek Interchange Dedicated by Road Chief |url=https://www.newspapers.com/clip/119732814/spring-creek-interchange-dedicated-by/ |pages=3, [https://www.newspapers.com/clip/119732880/dedication-held-at-interchange/ 14] |work=The Chattanooga Times |access-date=February 26, 2023 |via=Newspapers.com}}</ref> The first major section to be completed was the western ascent of Monteagle Mountain, which stretched from US&nbsp;64 near Pelham to US&nbsp;41 in Monteagle and eliminated a stretch of US&nbsp;41 with several hazardous hairpin curves.<ref>{{cite news |title = '$3 Million Horseshoe' Completed on U.S. Route 41 near Monteagle |url = https://www.newspapers.com/clip/97302813/3-million-horseshoe-completed-on/ |access-date = March 10, 2022 |work = The Chattanooga Times |date = February 25, 1962 |page = 11 |via = Newspapers.com }}</ref> Work began in September 1958,<ref>{{cite news |last1 = Peters |first1 = Mouzon |title = $1.5 Million Freeway Job to Take at Least Another Year to Complete |url = https://www.newspapers.com/clip/97302395/15-million-freeway-job-to-take-at/ |access-date = March 10, 2022 |work = The Chattanooga Times |date = August 19, 1959 |page = 14 |via = Newspapers.com }}</ref> and the stretch opened to traffic on February 6, 1962.<ref>{{cite news |last1 = Morrell |first1 = Ken |title = Monteagle Highway Opened |url = https://www.newspapers.com/clip/97303197/monteagle-highway-opened/ |access-date = March 10, 2022 |work = [[The Nashville Banner]] |date = February 6, 1962 |pages = 1, [https://www.newspapers.com/clip/97303160/monteagle-highway-is-opened/ 8] |via = Newspapers.com }}</ref> The short segment in Chattanooga between Belvoir Avenue and I-75 opened in late October 1962.<ref>{{cite news |author=<!--not stated--> |date=October 27, 1962 |title=One Section of Freeway Opened, Another Soon to Be (photos) |url=https://www.newspapers.com/clip/119733571/one-section-of-freeway-opened-another/ |page=3 |work=Chattanooga Daily Times |access-date=February 26, 2023 |via=Newspapers.com}}</ref> This was followed by the short stretch between east of the railyard and Fourth Avenue on January 3, 1963.<ref>{{cite news |title=Freeway Section Is Opened (photo) |url=https://www.newspapers.com/article/chattanooga-daily-times-freeway-section/136186240/ |access-date=December 3, 2023 |work=Chattanooga Daily Times |date=January 4, 1963 |page=1 |via=Newspapers.com}}</ref><ref>{{cite news |title=Freeways Aiding City Motorists |url=https://www.newspapers.com/article/chattanooga-daily-times-freeways-aiding/136186270/ |access-date=December 3, 2023 |work=Chattanooga Daily Times |date=January 16, 1963 |page=20 |via=Newspapers.com}}</ref> 

In Nashville, a short segment of the concurrent segment with I-40, located between Fesslers Lane and the eastern interchange with that route, was declared complete on January 11, 1965.<ref>{{cite news |title = Second Access to I-40 Opens |url = https://tennessean.newspapers.com/clip/86540083/the-tennessean/ |access-date = February 20, 2022 |work = The Nashville Tennessean |date = January 12, 1965 |page = 13 |via = Newspapers.com }}</ref> The section between the western  interchange with I-40 (then also I-65) and Fesslers Lane was partially opened in late December 1963<ref name="Kovach">{{cite news |last = Kovach |first = Bill |title = Evans Bridge Handling 10,000 Cars a Day |url = https://www.newspapers.com/clip/34066022/downtown-interstate-december-1963/ |page = 8A |work = The Nashville Tennessean |date = December 29, 1963 |access-date = July 15, 2020 |via = Newspapers.com }}</ref> and fully opened on April 19, 1965.<ref>{{cite news |author = <!--Staff writer(s)/no by-line.--> |date = April 16, 1965 |title = Sections to Open on I-40, I-65 |url = https://www.newspapers.com/clip/88906739/sections-to-open-on-i-40-i-65/ |page = 19 |work = The Nashville Tennessean |access-date = November 15, 2021 |via = Newspapers.com }}</ref> The Silliman Evans Bridge, along with the stretch extending from US 41 (First Street) and I-40 was dedicated on January 14, 1964.<ref>{{cite news |last = Caldwell |first = Nat |title = Silliman Evans Bridge Dedicated |url = https://www.newspapers.com/clip/14626522/the-tennessean/ |page = 1 |work = The Nashville Tennessean |date = January 15, 1964 |access-date = March 15, 2020 |via = Newspapers.com }}</ref> On July 27, 1965, the short section between US&nbsp;431 (Trinity Lane) and US 41 (First Street) was opened.<ref>{{cite news |author = <!--not stated--> |date = July 24, 1965 |title = Road to Open |url = https://www.newspapers.com/clip/98067136/road-to-open/ |work = The Nashville Tennessean |access-date = March 21, 2022 |via = Newspapers.com }}</ref> This section included provisions for the southern interchange with I-65 (then I-265), which had not been built yet. The Ridge Cut section in Chattanooga, which spanned between Fourth Avenue and Germantown Road, was dedicated on December 1, 1965.<ref name="Ridge Cut">{{cite news |last = Jolley |first = Harmon |date = April 2, 2003 |title = Your Tax Dollars at Work: Ridge Cut |url = http://www.chattanoogan.com/2003/4/2/34671/Your-Tax-Dollars-At-Work---Ridge-Cut.aspx |work = [[The Chattanoogan]] |access-date = June 25, 2018 |archive-date = June 26, 2018 |archive-url = https://web.archive.org/web/20180626054528/http://www.chattanoogan.com/2003/4/2/34671/Your-Tax-Dollars-At-Work---Ridge-Cut.aspx |url-status = live }}</ref><ref>{{cite news |last1=Davis |first1=Michael |title=50 years later ...Interstate network transformed U.S. transportation system |url=https://digital.olivesoftware.com/olive/apa/timesfreepress/sharedview.article.aspx?href=CHATTFPRESS%2F2006%2F06%2F29&id=Ar00105&sk=3881BC07&viewMode=text |access-date=December 3, 2023 |work=Chattanooga Times Free Press |date=June 29, 2006}}</ref> To construct the segment at the foot of Lookout Mountain west of downtown Chattanooga, engineers shifted the river channel to the north in order to avoid impeding the flow. This was accomplished by dredging out the north bank and filling in along the south bank with approximately {{Convert|250000|ST|t LT}} of rock from a nearby quarry.<ref name="Bend">{{cite news |last = Jolley |first = Harmon |date = April 6, 2003 |title = Your Tax Dollars at Work: I-24 Around Moccasin Bend |url = https://www.chattanoogan.com/2003/4/6/34843/Your-Tax-Dollars-At-Work---I-24-Around.aspx |work = The Chattanoogan |access-date = August 11, 2020 |archive-date = September 21, 2021 |archive-url = https://web.archive.org/web/20210921233507/https://www.chattanoogan.com/2003/4/6/34843/Your-Tax-Dollars-At-Work---I-24-Around.aspx |url-status = live }}</ref> This stretch of I-24, which spanned from US&nbsp;41 in Lookout Valley to 23rd Street near downtown Chattanooga, was completed on December 16, 1966, at a cost of approximately $15&nbsp;million (equivalent to ${{formatprice|{{inflation|US-GDP|15000000|1966}}}} in {{inflation-year|US-GDP}}{{inflation-fn|index=US-GDP}}), making it one of the most expensive highway projects, per mile, at the time.<ref>{{cite news |title = Gov. Frank Clement Dedicates What Is Probably State's Costliest Road |url = https://www.newspapers.com/clip/97301200/gov-frank-clement-dedicates-what-is/ |access-date = March 10, 2022 |work = [[Johnson City Press-Chronicle]] |agency = [[United Press International]] |date = December 17, 1966 |page = 2 |via = Newspapers.com }}</ref> 

I-24 was complete in Marion County to Monteagle Mountain in late 1966 and between US&nbsp;41 in Manchester and US&nbsp;64 near Pelham on July 27, 1967.<ref>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = 12 Miles of I-24 to Open Today |url = https://www.newspapers.com/clip/56532644/12-miles-of-i-24-to-open-today/ |page = 46 |work = The Nashville Tennessean |date = July 27, 1967 |access-date = July 31, 2020 |via = Newspapers.com }}</ref> The short segment between SR&nbsp;27 and SR&nbsp;156 in Marion County, including the bridge over Nickajack Lake, opened on December 18, 1967.<ref>{{cite news |author = <!--Staff writer(s)/no by-line.--> |title = I-24 Span Opened South of Jasper |url = https://tennessean.newspapers.com/clip/69451789/i-24-span-opened-south-of-jasper/ |page = 4 |work = [[The Tennessean]] |location = Nashville |date = December 19, 1967 |access-date = February 5, 2021 |via = Newspapers.com }}</ref> The stretch between US&nbsp;41 in Lookout Valley and the interchange with I-59 in Dade County, Georgia, was jointly opened to traffic by both states on September 10, 1968, along with the {{convert|8|mi|km|adj=pre|-northernmost-|spell=in}} of I-59.<ref>{{cite news |author = <!--Staff writer(s)/no by-line.--> |title = Federal Freeze to Delay Funds for Georgia Highways |url = https://www.newspapers.com/clip/69453595/federal-freeze-to-delay-funds-for/ |page = 18 |work = The Atlanta Constitution |agency = United Press International |date = September 12, 1968 |access-date = February 5, 2021 |via = Newspapers.com }}</ref> This was followed by the adjacent section extending west to SR 156 in early November 1968.<ref>{{cite news |title=New Interstate Links To Open |url=https://www.newspapers.com/article/the-jackson-sun-new-interstate-links-to/136187590/ |access-date=December 3, 2023 |work=The Jackson Sun |date=October 20, 1968 |page=3}}</ref><ref>{{cite news |title=Three Interstate Sections To Open In Next Few Weeks |url=https://www.newspapers.com/article/elizabethton-star-three-interstate-secti/136187011/ |access-date=December 3, 2023 |work=Elizabethton Star |agency=United Press International |date=October 21, 1968 |pages=1, [https://www.newspapers.com/article/elizabethton-star-three-interstate/136187031/ 6]}}</ref> In Nashville, the short section between US&nbsp;431 and the northern interchange with I-65, along with a short stretch of I-65 north of this section, opened to traffic on December 23, 1968.<ref>{{cite news |last = Fontenay |first = Charles |date = January 12, 1969 |title = Interstate Traffic Still Stalls in Metropolitan Nashville |url = https://www.newspapers.com/clip/6341112/christmas-68-enashville-portion-of/ |page = 86 |work = The Nashville Tennessean |access-date = March 26, 2020 |via = Newspapers.com }}</ref> The section between US 41 in northwestern Coffee County and US 41 in Manchester opened on December 3, 1969.<ref>{{cite news |author=<!--not stated--> |date=December 4, 1969 |title=I-24 Bypass Opened Around Manchester |url=https://www.newspapers.com/article/the-tennessean-i-24-bypass-opened-around/131538176/ |page=66 |work=The Nashville Tennessean |access-date=September 10, 2023 |via=Newspapers.com}}</ref> On December 9, 1970, I-24 opened between US&nbsp;231 in Murfreesboro and SR&nbsp;64 near Beechgrove.<ref>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = I-24 Section Opened Today |url = https://www.newspapers.com/clip/63071950/i-24-section-opened-today/ |page = 1 |work = The Daily News-Journal |location = Murfreesboro, Tennessee |date = December 9, 1970 |access-date = November 12, 2020 |via = Newspapers.com }}</ref> The route was opened between SR&nbsp;171 in Nashville and US&nbsp;231 in Murfreesboro on December 31, 1970.<ref>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = New I-24 Section to Open |url = https://www.newspapers.com/clip/56532693/new-i-24-section-to-open/ |page = 14 |work = The Nashville Tennessean |date = December 31, 1970 |access-date = June 27, 2020 |via = Newspapers.com }}</ref> The last segment of I-24 between Nashville and Chattanooga, the segment located between SR&nbsp;64 near Beechgrove and US&nbsp;41 northwest of Manchester, was let to contract on January 31, 1969,<ref>{{cite news |title=I-24 Linkage Contracts Let |url=https://www.newspapers.com/article/the-tennessean-i-24-linkage-contracts-le/136190116/ |access-date=December 3, 2023 |work=The Nashville Tennessean |date=February 1, 1969 |page=16}}</ref> and opened and dedicated on December 16, 1971.<ref>{{cite news |last = Kollar |first = Robert |date = December 17, 1971 |title = It'll Be Clear Sailing to Chattanooga Now |url = https://www.newspapers.com/clip/56532780/itll-be-clear-sailing-to-chattanooga/ |page = 21 |work = The Nashville Tennessean |access-date = July 31, 2020 |via = Newspapers.com }}</ref>

Construction began on I-24 between the Kentucky line and SR 48 in Clarksville on April 12, 1971.<ref>{{cite news |author=<!--not stated--> |date=April 18, 1971 |title=Work Rapid On 24 |url=https://www.newspapers.com/article/the-leaf-chronicle-work-rapid-on-24/133804862/ |pages=1, [https://www.newspapers.com/article/the-leaf-chronicle-work-rapid/133804895/ 8] |work=Clarksville Leaf-Chronicle |access-date=November 28, 2023 |via=Newspapers.com}}</ref> In February 1972, the FHWA announced that it was redistributing funds that had been budgeted for Interstate construction in Tennessee to other states which were further behind on their Interstates. I-24 between Nashville and Kentucky was one of the sections affected by this cutback, which threatened to delay completion.<ref>{{cite news |last=Charlet |first=Jim |date=February 9, 1972 |title=Lid Clamped On I-24 Construction |url=https://www.newspapers.com/article/the-leaf-chronicle-lid-clamped-on-i-24-c/135941631/ |pages=1, [https://www.newspapers.com/article/the-leaf-chronicle-lid-clamped-on-i-24/135942435/ 2] |work=Clarksville Leaf-Chronicle |access-date=November 28, 2023 |via=Newspapers.com}}</ref> In response, the state legislature authorized the issuance of $100 million (equivalent to ${{formatprice|{{inflation|US-GDP|100000000|1972}}}} in {{inflation-year|US-GDP}}{{inflation-fn|US-GDP}}) in bonds to finance the completion of I-24.<ref>{{cite news |author=<!--not stated--> |date=July 5, 1972 |title=State Will Have 828 Miles Of Interstate By Jan. 1 |url=https://theleafchronicle.newspapers.com/article/the-leaf-chronicle-state-will-have-828-m/135942938/ |page=2  |work=Clarksville Leaf-Chronicle |agency=Associated Press |access-date=November 28, 2023 |via=Newspapers.com}}</ref><ref>{{cite news |last=Rawlins |first=Bill |date=July 6, 1972 |title=I-24 Bid Call Set This Fall |url=https://theleafchronicle.newspapers.com/article/the-leaf-chronicle-i-24-bid-call-set-thi/135943456/ |pages=1, [https://theleafchronicle.newspapers.com/article/the-leaf-chronicle-i-24-bid/135943478/ 2] |work=Clarksville Leaf-Chronicle |agency=Associated Press |access-date=November 28, 2023 |via=Newspapers.com}}</ref> This allowed for TDOT to let contracts for the remaining sections between Nashville and Clarksville from  September to November 1972.<ref>{{cite news |author=<!--not stated--> |date=August 27, 1972 |title=Bidding Begins Next Month For Portions Of I-24 |url=https://www.newspapers.com/article/the-leaf-chronicle-bidding-begins-next-m/135941777/ |page=5 |work=Clarksville Leaf-Chronicle |access-date=November 28, 2023 |via=Newspapers.com}}</ref><ref>{{cite news |author=<!--not stated--> |date=September 27, 1972 |title=Bridge Bids Proposed |url=https://www.newspapers.com/article/the-leaf-chronicle-bridge-bids-proposed/135944072/ |work=Clarksville Leaf-Chronicle |access-date=November 28, 2023 |via=Newspapers.com}}</ref><ref>{{cite news |author=<!--not stated--> |date=October 20, 1972 |title=Bids Nov. 17 On I-24 Work |url=https://www.newspapers.com/article/the-memphis-press-scimitar-bids-nov-17/135944265/ |page=15  |work=Memphis Press-Scimitar |agency=United Press International |access-date=November 28, 2023 |via=Newspapers.com}}</ref> Once construction on the remainder of I-24 between Clarksville and Nashville was underway, the route was projected to be completed in late 1974 or early 1975, but would experience further delays as a result of geological problems.<ref name=leaf78/> Construction on this approximately {{convert|44|mi|km|adj=on}} segment, the last segment of mainline Interstate Highway completed in Tennessee, proved to be difficult due to the rugged and hilly terrain.<ref>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = Interstate Completion by New Year? Maybe |url = https://www.newspapers.com/clip/56532894/interstate-completion-by-new-year-maybe/ |work = Clarksville Leaf-Chronicle |date = December 28, 1977 |access-date = April 27, 2019 |via = Newspapers.com }}</ref> The approximately {{convert|32|mi|km|adj=on}} segment between US&nbsp;68 in Hopkinsville, Kentucky, and US&nbsp;79 in Clarksville, Tennessee, was jointly opened to traffic by both states on September 12, 1975.<ref>{{cite news |title = Carroll to Open Section of Interstate 24 Friday |work = Kentucky New Era |date = September 11, 1975 }}{{page needed|date=June 2022}}</ref><ref>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = First I-24 Section Opens |url = https://www.newspapers.com/clip/56532959/first-i-24-section-opens/ |work = Clarksville Leaf-Chronicle |date = September 14, 1975 |access-date = April 27, 2019 |via = Newspapers.com }}</ref> The {{convert|15|mi|km|adj=on}} section between US&nbsp;79 and SR&nbsp;49 in Robertson County was completed in September 1976.<ref>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = Local News Notes  |url = https://www.newspapers.com/clip/56533010/i-24-progress/ |work = Clarksville Leaf-Chronicle |date = December 8, 1976 |access-date = April 27, 2019 |via = Newspapers.com }}</ref> The last segment of I-24 in Tennessee, between SR&nbsp;49 and I-65 in Nashville, was opened to traffic on January 5, 1978, more than two years behind schedule.<ref name=leaf78>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = I-24 Opens |url = https://www.newspapers.com/clip/56532840/i-24-opens/ |work = [[Clarksville Leaf-Chronicle]] |date = January 6, 1978 |access-date = April 27, 2019 |via = Newspapers.com }}</ref><ref>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = Motorists Wait as Final Link of I-24 Opens |url = https://www.newspapers.com/clip/56533053/motorists-wait-as-final-link-of-i-24/ |work = The Tennessean |location = Nashville |date = January 8, 1978 |access-date = April 27, 2019 |via = Newspapers.com }}</ref>

The Silliman Evans Bridge was widened from six to eight lanes in a project that completely closed the northbound span between January 20, 1974, and April 6, 1975, and the southbound span from April 6, 1975, to November 16, 1975.<ref name="Lewis">{{cite news |last = Lewis |first = Dwight |date = January 18, 1974 |title = Northbound Evans Bridge to Close for Year Sunday |url = https://www.newspapers.com/clip/70378910/northbound-evans-bridge-to-close-for/ |page = 20 |work = The Tennessean |location = Nashville |access-date = February 13, 2021 |via = Newspapers.com }}</ref><ref>{{cite news |date = April 9, 1975 |title = Silliman Evans Bridge Span Open |url = https://www.newspapers.com/clip/70384378/silliman-evans-bridge-span-open/ |page = 1 |work = The Tennessean |location = Nashville |access-date = February 13, 2021 |via = Newspapers.com }}</ref><ref>{{cite news |date = November 14, 1975 |title = Lanes Open Sunday |url = https://www.newspapers.com/clip/70382759/lanes-open-sunday/ |page = 1 |work = The Tennessean |location = Nashville |access-date = February 13, 2021 |via = Newspapers.com }}</ref> This project also added shoulders to the bridge and removed railings that had been deemed unsafe and were believed to have played a role in multiple fatal accidents on the bridge.<ref name="Lewis"/> 

[[File:I24 bridge.jpg|thumb|upright=2|[[I-24 Bridge]] connecting Illinois with Kentucky across the [[Ohio River]]]]
A groundbreaking ceremony for the first stretch of I-24 in Kentucky was held on December 6, 1967, in Lyon County.<ref>{{cite news |last1 = Powell |first1 = Bill |title = Breathitt to Break Ground for Well-Advanced Interstate 24 |url = https://www.newspapers.com/clip/102947130/breathitt-to-break-ground-for/ |access-date = June 1, 2022 |work = Sun-Democrat |date = December 4, 1967 |location = Paducah, Kentucky |pages = 1, [https://www.newspapers.com/clip/102947224/breathitt/ 2] |via = Newspapers.com }}</ref><ref>{{cite news |title = I-24 Work Is Started Without Gov. Breathitt |url = https://www.newspapers.com/clip/102946931/i-24-work-is-started-without-gov/ |access-date = June 1, 2022 |work = [[The Courier-Journal]] |agency = Associated Press |date = December 7, 1967 |location = Louisville, Kentucky |page = A29 |via = Newspapers.com }}</ref> The section of I-24 in Illinois was authorized for engineering by 1966 and authorized for construction by 1968.<ref name="67bluebook">{{cite book |author = Office of Secretary of State |title = Illinois Blue Book, 1967–1968 |year = 1967 |publisher = State of Illinois |url = http://www.idaillinois.org/cdm/compoundobject/collection/bb/id/20934 |access-date = January 9, 2011 |page = 746 |via = Illinois Digital Archives |archive-date = February 1, 2014 |archive-url = https://web.archive.org/web/20140201175330/http://www.idaillinois.org/cdm/compoundobject/collection/bb/id/20934 |url-status = live }}</ref><ref name="65bluebook">{{cite book |author = Office of Secretary of State |title = Illinois Blue Book, 1965–1966 |year = 1965 |publisher = State of Illinois |url = http://www.idaillinois.org/cdm/compoundobject/collection/bb/id/16489 |access-date = January 9, 2011 |page = 720 |via = Illinois Digital Archives |archive-date = February 1, 2014 |archive-url = https://web.archive.org/web/20140201182342/http://www.idaillinois.org/cdm/compoundobject/collection/bb/id/16489 |url-status = live }}</ref> The first section of I-24 in Illinois, located between US&nbsp;45 in Vienna and US&nbsp;45 in Metropolis, was dedicated and opened by Governor [[Dan Walker (politician)|Dan Walker]] on January 15, 1974.<ref>{{cite news |title = 21-Mile Section of Interstate 24 Opened Tuesday by Gov. Walker |url = https://www.newspapers.com/clip/102947915/21-mile-section-of-interstate-24-opened/ |access-date = June 1, 2022 |work = Hardin County Independent |date = January 17, 1974 |location = Elizabethtown, Illinois |page = 1 |via = Newspapers.com }}</ref> On October 18, 1974, the stretch between US&nbsp;45 in Metropolis and US&nbsp;60 in Paducah, including the Ohio River bridge, opened to traffic.<ref>{{cite news |title = Traffic Flow Is Improved as I-24 Bridge in Operation |url = https://www.newspapers.com/clip/102948582/traffic-flow-is-improved-as-i-24-bridge/ |access-date = June 1, 2022 |work = Sun-Democrat |date = October 18, 1974 |location = Paducah, Kentucky |page = 1A |via = Newspapers.com }}</ref> This was also the first stretch of I-24 to open in Kentucky.<ref name=sun80/> The final segment of I-24 in Illinois, located between I-57 and US&nbsp;45 in Vienna, was dedicated and opened to traffic by Governor Walker on January 24, 1976.<ref>{{cite news |title = Interstate 24 Opened at Pulleys Mill |url = https://www.newspapers.com/clip/102950596/interstate-24-opened-at-pulleys-mill/ |access-date = June 1, 2022 |work = Southern Illinoisan |date = January 25, 1976 |location = Carbondale, Illinois |page = 1 |via = Newspapers.com }}</ref> In October 1977, the stretch between US&nbsp;68 in Reidland and US&nbsp;62 east of Calvert City was completed.<ref name=sun80/> 

The {{convert|2.5|mi|km|adj=on}} section between US&nbsp;62 near Calvert City and KY&nbsp;453, including the Tennessee River Bridge, which had been completed approximately five years prior, was opened to traffic on October 25, 1979.<ref>{{cite news |last1 = Powell |first1 = Bill |title = New Portion of I-24 Allows Use of Bridge over Tennessee River |url = https://www.newspapers.com/clip/102950315/new-portion-of-i-24-allows-use-of/ |access-date = June 1, 2022 |work = The Courier-Journal |date = June 27, 1979 |location = Louisville, Kentucky |page = B1 |via = Newspapers.com }}</ref> The section between US&nbsp;60 in Paducah and US&nbsp;68 in Reidland was opened and dedicated by Governor [[Julian Carroll]] on December 15, 1978.<ref>{{cite news |last1 = Matlock |first1 = Bill |title = Carroll Aiming for I-24 Wrap-Up Before He's Out |url = https://www.newspapers.com/clip/102949027/carroll-aiming-for-i-24-wrap-up-before/ |access-date = June 1, 2022 |work = The Paducah Sun |date = December 17, 1978 |page = 2A |via = Newspapers.com }}</ref> On December 10, 1979, the stretch between KY&nbsp;453 and US&nbsp;60/[[U.S. Route 641 in Tennessee|US&nbsp;641]] in Eddyville, including the Cumberland River Bridge, was opened.<ref>{{cite news |last1 = Powell |first1 = Bill |title = Carroll Spends Last Day Spreading Good News |url = https://www.newspapers.com/clip/102949568/carroll-spends-last-day-spreading-good/ |access-date = June 1, 2022 |work = The Courier-Journal |date = December 11, 1979 |location = Louisville, Kentucky |page = B5 |via = Newspapers.com }}</ref> Construction on the bridge began in 1972, but issues caused by unusual rock formations at the site, believed to have been formed by the [[1811–1812 New Madrid earthquakes]] or earlier quakes, delayed completion and resulted in the cost nearly tripling.<ref>{{cite news |last1 = Powell |first1 = Bill |title = A Shock to the Budget: Unexplained Quake Damage Shot Bridge's Cost Sky-High |url = https://www.newspapers.com/clip/102949784/a-shock-to-the-budget/ |access-date = June 1, 2022 |work = The Courier-Journal |date = September 20, 1979 |location = Louisville, Kentucky |pages = A1, [https://www.newspapers.com/clip/102949843/earthquake-shot-the-cost-of-bridge/ A12] |via = Newspapers.com }}</ref> On March 20, 1980, the {{convert|2.7|mi|km|adj=on}} stretch in Eddyville between US&nbsp;62/US&nbsp;641 and the Western Kentucky Parkway (now I-69), along with the westernmost {{convert|3.4|mi|km}} of the latter route, was opened.<ref>{{cite news |last1 = Powell |first1 = Bill |title = New Part of I-24 Finishes 4-Lane Route Across State |url = https://www.newspapers.com/clip/102950093/new-part-of-i-24-finishes-4-lane-route/ |access-date = June 1, 2022 |work = The Courier-Journal |date = March 21, 1980 |location = Louisville, Kentucky |page = B1 |via = Newspapers.com }}</ref> I-24 was completed when the {{convert|23|mi|km|adj=on}} section opened to traffic from what is now I-69 to US&nbsp;68 east of Cadiz on May 23, 1980.<ref name=sun80>{{cite news |last1 = Bartleman |first1 = Bill |title = At Last, an Unbroken I-24 from Here South |url = https://www.newspapers.com/clip/102946706/at-last-an-unbroken-i-24-from-here/ |access-date = June 1, 2022 |work = The Paducah Sun |date = May 22, 1980 |pages = 1A, [https://www.newspapers.com/clip/102946664/i-24-final-segment-opening/ 12A] |via = Newspapers.com }}</ref><ref>{{cite news |last1 = Powell |first1 = Bill |title = After 23 Years, Final Link of I-24 Will Open Without Fanfare |url = https://www.newspapers.com/clip/102946200/after-23-years-final-link-of-i-24-will/ |access-date = June 1, 2022 |work = The Courier-Journal |date = May 22, 1980 |location = Louisville, Kentucky |pages = B1, [https://www.newspapers.com/clip/102946273/final-segment-of-interstate-24-to/ B2] |via = Newspapers.com }}</ref>

In November 1977, the [[Tennessee Department of Transportation]] (TDOT) installed a system to detect [[tailgating]] vehicles in the westbound lanes of the concurrent segment with I-40, which consisted of sensors embedded in the roadway connected to overhead warning signs with flashing lights and horns.<ref>{{cite news |last = Gibson |first = Frank |date = November 26, 1977 |title = Sensors Lurk on Interstates for Tailgaters |url = https://tennessean.newspapers.com/clip/88272867/sensors-lurk-on-interstates-for/ |page = 1, [https://tennessean.newspapers.com/clip/88273191/tailgating-sensors-set-on-interstates/ 6] |work = The Tennessean |location = Nashville |access-date = November 3, 2021 |via = Newspapers.com }}</ref><ref>{{cite news |date = December 1, 1977 |title = Checking on Tailgaters |url = https://tennessean.newspapers.com/clip/88272749/checking-on-tailgaters/ |page = 14 |work = The Tennessean |location = Nashville |access-date = November 3, 2021 |via = Newspapers.com }}</ref> The system was the first of its kind in the country but experienced technical problems and was criticized as ineffective, leading to its decommission in July 1980.<ref>{{cite news |last = Travis |first = Fred |date = October 14, 1980 |title = Another Expensive Boondoggle |url = https://www.newspapers.com/clip/88273757/another-expensive-boondoggle/ |page = 10A |work = The Leaf-Chronicle |location = Clarksville, Tennessee |access-date = November 3, 2021 |via = Newspapers.com }}</ref> This segment was widened from six to eight lanes between July 1979 and January 1980 by removing the right shoulders, narrowing the lanes by {{convert|1|ft|m|spell=in}}, and shifting traffic slightly to the left.<ref>{{cite news |date = May 28, 1979 |title = Motorists Face I-40 Disruption |url = https://tennessean.newspapers.com/clip/88276594/motorists-face-i-40-disruption/ |page = 16 |work = The Tennessean |location = Nashville |access-date = November 3, 2021 |via = Newspapers.com }}</ref><ref>{{cite news |date = July 12, 1979 |title = Work to Widen I-24-40 Lanes Scheduled to Begin Today |url = https://tennessean.newspapers.com/clip/88275815/work-to-widen-i-24-40-lanes-scheduled/ |page = 15 |work = The Tennessean |location = Nashville |access-date = November 3, 2021 |via = Newspapers.com }}</ref>

A project began in April 1985 that extensively straightened and rebuilt the eastbound lanes of I-24 on the eastern downgrade of Monteagle Mountain and reduced the grade.<ref name=tennessean>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = New I-24 Lanes Opened at Monteagle |url = https://www.newspapers.com/clip/50191131/new-i-24-lanes-opened-at-monteagle/ |work = The Tennessean |location = Nashville |agency = Associated Press |date = July 12, 1989 |page = 2B |issn = 1053-6590 |access-date = May 4, 2020 |via = Newspapers.com }}</ref> The project also added left shoulders and an additional runaway truck ramp, the latter of which was not originally planned.<ref name=tennessean2>{{cite news |author = <!--Staff writer(s); no by-line.--> |title = New I-24 Stretch to Open July 11 |url = https://www.newspapers.com/clip/50191031/new-i-24-stretch-to-open-july-11/ |work = The Tennessean |location = Nashville |agency = Associated Press |date = July 6, 1989 |page = 3B |issn = 1053-6590 |access-date = May 4, 2020 |via = Newspapers.com }}</ref> This work was completed in 1989, and the lanes were reopened on July 11 of that year in a ceremony officiated by Governor [[Ned McWherter]].<ref name=tennessean/> The project experienced many setbacks including geological problems, which caused extensive delays.<ref name=tennessean3/> Originally targeted for completion in December 1987 at a cost of $17&nbsp;million (equivalent to ${{formatprice|{{inflation|US-GDP|17000000|1987}}}} in {{inflation-year|US-GDP}}{{inflation-fn|index=US-GDP}}), the final cost was $29.5&nbsp;million (equivalent to ${{formatprice|{{inflation|US-GDP|29500000|1989}}}} in {{inflation-year|US-GDP}}{{inflation-fn|index=US-GDP}}).<ref name=tennessean/> During this project, both directions of traffic were routed to the westbound lanes of I-24, which were separated by a [[Jersey barrier]], and a temporary runaway truck ramp for eastbound traffic was also provided along this alignment.<ref name=tennessean3>{{cite news |last = George |first = Dan |title = I-24 East over Monteagle Likely Open Next Summer |url = https://www.newspapers.com/clip/50191231/i-24-east-over-monteagle-likely-open/ |work = The Tennessean |location = Nashville |agency = Associated Press |date = December 16, 1988 |page = 21A |issn = 1053-6590 |access-date = May 4, 2020 |via = Newspapers.com }}</ref> A truck station to allow for the adjustment of brakes opened in January 1992.<ref name=commerce/> After the safety improvements were completed, accidents in the eastbound lanes of this stretch dropped from 54 in 1983 to 3 in 1991.<ref name=commerce>{{cite news |last = Salomon |first = Alan |date = March 17, 1992 |title = Once-Defenseless Truckers Grateful as Tennessee 'Tames' Killer Mountain |url = https://www.joc.com/once-defenseless-truckers-grateful-tennessee-tames-killer-mountain_19920317.html |work = [[Journal of Commerce]] |access-date = April 28, 2019 |archive-date = April 28, 2019 |archive-url = https://web.archive.org/web/20190428060226/https://www.joc.com/once-defenseless-truckers-grateful-tennessee-tames-killer-mountain_19920317.html |url-status = live }}</ref>


The {{convert|4.7|mi|km|adj=on}} stretch between near SR&nbsp;255 (Harding Place) and near SR&nbsp;254 (Bell Road) was widened to six lanes between April 1989 and November 1990.<ref>{{cite news |title = Nashville Road Work |url = https://tennessean.newspapers.com/clip/101768732/nashville-road-work/ |access-date = May 13, 2022 |work = The Tennessean |date = July 2, 1990 |location = Nashville |page = 4B |via = Newspapers.com }}</ref><ref name="awards">{{cite web |url = https://www.tn.gov/content/dam/tn/tdot/documents/business-how-do-i-documents/Const_n87-91%20(1).pdf |title = 1987–1991 Contract Awards |author = Tennessee Department of Transportation |publisher = Tennessee Department of Transportation |access-date = July 7, 2020 |archive-date = January 24, 2020 |archive-url = https://web.archive.org/web/20200124101423/https://www.tn.gov/content/dam/tn/tdot/documents/business-how-do-i-documents/Const_n87-91%20(1).pdf |url-status = live }}</ref> Between November 1994 and November 1995, TDOT made safety modifications to I-24 through the eastern terminus with I-440 and the nearby split with I-40, which reconfigured the routes to provide direct access to I-440 westbound from I-40 westbound, splitting I-24's eastbound lanes into two barrier-separated carriageways.<ref>{{cite news |last = Ferguson |first = Carrie |date = October 28, 1994 |title = First Stage of Interstate Relief Expected Soon |url = https://tennessean.newspapers.com/clip/62839793/first-stage-of-interstate-relief/ |page = 1A |work = The Tennessean |location = Nashville |access-date = November 8, 2020 |via = Newspapers.com }}</ref><ref>{{cite news |last = Kerr |first = Gail |date = September 23, 1995 |title = Old I-440 Dash Thing of the Past |url = https://tennessean.newspapers.com/clip/62837264/old-i-440-dash-thing-of-the-past/ |page = 1B |work = The Tennessean |location = Nashville |access-date = November 8, 2020 |via = Newspapers.com }}</ref>

The approximately {{convert|9.3|mi|km|adj=on}} segment between Haywood Lane in Nashville and SR&nbsp;266 in Smyrna was widened from four to eight lanes between June 1997 and December 1998, installing the first HOV lanes on I-24.<ref>{{cite press release |author = <!--Staff writer(s); no by-line.--> |title = New Lanes to Open on I-24 |url = http://www.tdot.state.tn.us/information-office/press98.htm#014 |publisher = Tennessee Department of Transportation |date = November 30, 1998 |access-date = February 7, 2020 |url-status = dead |archive-url = https://web.archive.org/web/20000824052824/http://www.tdot.state.tn.us/information-office/press98.htm#014 |archive-date = August 24, 2000 }}</ref> The {{convert|8.2|mi|km|adj=on}} portion between SR&nbsp;266 and I-840 was widened from four to eight lanes between August 1998 and November 2000. The {{convert|4|mi|km|spell=in|adj=on}} segment between I-440 and Haywood Lane was widened from three to four lanes in each direction between March 2000 and May 2002 in a project that also improved the interchanges on this segment.<ref>{{cite press release |author = <!--Staff writer(s); no by-line.--> |title = Final Paving Begins on I-24: Project Finishes Six Weeks Early |url = http://www.tdot.state.tn.us/information-office/2002pr/Apr2002.htm |publisher = Tennessee Department of Transportation |date = April 17, 2002 |access-date = February 7, 2020 |url-status = dead |archive-url = https://web.archive.org/web/20030625045107/http://www.tdot.state.tn.us/information-office/2002pr/Apr2002.htm |archive-date = June 25, 2003 }}</ref> Widening of the segment between I-840 and SR&nbsp;96 began in early 2004 and was completed in the summer of 2005.<ref name=Tennessean>{{cite news |last = Anderson |first = Matt |date = September 22, 2005 |title = Interstate 24 Is County's Transportation Lifeline |url = https://www.newspapers.com/clip/56537123/interstate-24-is-countys/ |work = The Tennessean |location = Nashville |access-date = June 18, 2018 |via = Newspapers.com }}</ref> This project added a new interchange at Medical Center Parkway. A project that widened I-24 from four to eight lanes between SR&nbsp;96 and US&nbsp;231, and also added a new interchange with SR&nbsp;99, began in April 2006 and was completed on January 28, 2008.<ref>{{cite press release |author = <!--Staff writer(s); no by-line.--> |title = I-24 Widening Project in Murfreesboro Complete Five Months Early |url = http://www.tdot.state.tn.us/news/2008/012808.htm |publisher = Tennessee Department of Transportation |date = January 28, 2008 |access-date = February 7, 2020 |url-status = dead |archive-url = https://web.archive.org/web/20080811214702/http://www.tdot.state.tn.us/news/2008/012808.htm |archive-date = August 11, 2008 }}</ref>

In Chattanooga, the stretch between the bottom of the Ridge Cut and east of the Big Scramble was widened from four to six lanes in the mid- to latter 1980s. Between May 1989 and November 1991, the Big Scramble was modified in a project that eliminated left-hand entrance and exit ramps, widened parts of the main carriageway, and converted the westbound lanes of I-24 into the ramp carrying I-24 westbound traffic to US&nbsp;27 northbound.<ref name="awards"/>

The original interchange with I-75, which was a simple directional T design, had repeatedly been ranked as one of the top 10 worst freight bottlenecks in the US by the American Transportation Research Institute and contained several sharp curves and other safety hazards. In December 2018, a contract was awarded to rebuild the interchange, with preliminary work beginning in May 2019.<ref>{{cite news |date = December 21, 2018 |title = TDOT: I-24/I-75 Interchange Project to Begin in 2019, Last Less than 3 Years |url = https://newschannel9.com/news/local/tdot-i-24i-75-interchange-project-to-begin-in-2019-last-less-than-3-years |publisher = WTVC-TV |location = Chattanooga, Tennessee |access-date = December 7, 2019 |archive-date = December 8, 2019 |archive-url = https://web.archive.org/web/20191208035422/https://newschannel9.com/news/local/tdot-i-24i-75-interchange-project-to-begin-in-2019-last-less-than-3-years |url-status = live }}</ref><ref>{{cite news |last = Benton |first = Ben |date = May 6, 2019 |title = Contractor Starts Early Work, Materials DDeliveries at I-75/I-24 'Split' |url = https://www.timesfreepress.com/news/local/story/2019/may/06/contractor-starts-early-work-materials-delive/494054/ |work = Chattanooga Times Free Press |access-date = December 7, 2019 |archive-date = December 8, 2019 |archive-url = https://web.archive.org/web/20191208035422/https://www.timesfreepress.com/news/local/story/2019/may/06/contractor-starts-early-work-materials-delive/494054/ |url-status = live }}</ref> The project consisted of eliminating left-hand entrance and exit ramps from I-75 onto I-24, straightening curves, widening I-75 to six lanes through the interchange, widening two ramps from I-75 to I-24 to three lanes, replacing two overpass bridges, and construction of a [[collector–distributor]] facility that carries traffic directly from US&nbsp;41 and the Tennessee Welcome Center along I-75 northbound, providing direct access to both I-75 northbound and I-24 westbound. Additional space was also provided to widen the remaining ramps between I-75 and I-24 to three lanes, which will be done in the second phase.<ref>{{cite web |title = Interstate 75 Interchange at Interstate 24 |url = https://www.tn.gov/tdot/projects/region-2/i-75-interchange-at-i-24.html |publisher = Tennessee Department of Transportation |access-date = August 23, 2021 |location = Nashville |date = 2018 |archive-date = August 23, 2021 |archive-url = https://web.archive.org/web/20210823010537/https://www.tn.gov/tdot/projects/region-2/i-75-interchange-at-i-24.html |url-status = live }}</ref> The project was completed on August 19, 2021, at a cost of $133.5&nbsp;million, making it the second-most expensive individual contract in state history at the time.<ref name=tfp0821>{{cite news |last1 = Benton |first1 = Ben |title = Phase 1 of Split Project Crosses Finish Line, but Bottleneck from I-75 North to I-24 Will Linger |url = https://www.timesfreepress.com/news/local/story/2021/aug/22/phase-1-split-project-crosses-finish-line-bot/552728/ |access-date = August 23, 2021 |work = Chattanooga Times Free Press |date = August 22, 2021 |archive-date = August 23, 2021 |archive-url = https://web.archive.org/web/20210823005734/https://www.timesfreepress.com/news/local/story/2021/aug/22/phase-1-split-project-crosses-finish-line-bot/552728/ |url-status = live }}</ref> The second phase will widen the adjacent segment of I-24 west of the interchange and lengthen auxiliary lanes on I-75 about {{convert|1.5|mi|km}} north of the interchange.<ref name=tfp0821/> In preparation for the second phase, the Belvoir Avenue overpass and Germantown Road underpass were replaced between May 2020 and August 2021; the latter replacement utilized [[accelerated bridge construction]] by shifting I-24 traffic onto the Germantown Road entrance and exit ramp and adjacent frontage roads.<ref>{{cite press release |date = April 15, 2020 |title = TDOT to Begin Bridge Replacement Project on Interstate 24 in Chattanooga |url = https://www.tn.gov/content/tn/tdot/news/2020/4/15/tdot-contractor-to-begin-bridge-replacement-project-on-interstate-24-in-chattanooga--hamilton-county.html |publisher = Tennessee Department of Transportation |access-date = May 13, 2022 |archive-date = May 13, 2022 |archive-url = https://web.archive.org/web/20220513062843/https://www.tn.gov/content/tn/tdot/news/2020/4/15/tdot-contractor-to-begin-bridge-replacement-project-on-interstate-24-in-chattanooga--hamilton-county.html |url-status = live }}</ref>

=== I-24 SMART Corridor ===
The {{convert|28|mi|km|adj=on}} stretch of I-24 between I-440 (exit&nbsp;53) in Nashville and US&nbsp;231 (exit&nbsp;81) in Murfreesboro is currently in the process of being developed into the "I-24 SMART Corridor" in an effort to address congestion and mobility issues.<ref>{{cite web |title = I-24 SMART Corridor |url = https://www.tn.gov/tdot/projects/region-3/i-24-smart-corridor.html |publisher = Tennessee Department of Transportation |access-date = May 13, 2022 |archive-date = April 17, 2022 |archive-url = https://web.archive.org/web/20220417120338/https://www.tn.gov/tdot/projects/region-3/i-24-smart-corridor.html |url-status = live }}</ref> In recent years, this stretch of I-24 has become the most congested highway corridor in the state, due to the rapid growth of the region. The project pairs this stretch with the adjacent paralleling stretch of US&nbsp;41/US&nbsp;70S (Murfreesboro Road) and all connecting roads in between. The first phase, which ran from October 2018 to December 2021, included the construction of emergency pull-offs, improvements to multiple entrance and exit ramps, the erection of additional roadside [[dynamic-message sign]]s (DMSs), and upgrades to traffic signals along the corridor.<ref name="SMARTtimeline">{{cite web |title = I-24 SMART Corridor Timeline |url = https://www.tn.gov/tdot/projects/region-3/i-24-smart-corridor/timeline.html |publisher = Tennessee Department of Transportation |access-date = May 13, 2022 |archive-date = May 13, 2022 |archive-url = https://web.archive.org/web/20220513053707/https://www.tn.gov/tdot/projects/region-3/i-24-smart-corridor/timeline.html |url-status = live }}</ref> The second phase, which began in March 2022, includes the erection of 67 overhead gantries with signs between mileposts&nbsp;53 and 70 that will display recommended [[variable speed limit]]s and variable lane control signs for each lane.<ref>{{cite news |last1 = Wenzel |first1 = Joe |last2 = Sulek |first2 = Marissa |title = TDOT: Construction to Start on Phase 2 of I-24 SMART Corridor Next Month |url = https://www.wsmv.com/2022/03/25/tdot-construction-start-phase-2-i-24-smart-corridor-next-month/ |access-date = May 13, 2022 |publisher = [[WSMV-TV]] |date = March 25, 2022 |location = Nashville, Tennessee |archive-date = March 25, 2022 |archive-url = https://web.archive.org/web/20220325165223/https://www.wsmv.com/2022/03/25/tdot-construction-start-phase-2-i-24-smart-corridor-next-month/ |url-status = live }}</ref><ref>{{cite news |last1 = McCarthy |first1 = Darby |title = I-24 SMART Corridor Project Begins Phase 2, Lane Closures from Nashville to Murfreesboro Beginning in April |url = https://www.newschannel5.com/news/i-24-smart-corridor-project-begins-phase-2-lane-closures-from-nashville-to-murfreesboro-beginning-in-april |access-date = May 13, 2022 |publisher = [[WTVF-TV]] |date = March 27, 2022 |location = Nashville, Tennessee |archive-date = April 19, 2022 |archive-url = https://web.archive.org/web/20220419110113/https://www.newschannel5.com/news/i-24-smart-corridor-project-begins-phase-2-lane-closures-from-nashville-to-murfreesboro-beginning-in-april |url-status = live }}</ref> The final phase will include the installation of [[ramp meter]]s on certain onramps and the installation of additional [[closed-circuit television]] (CCTV) cameras and DMS boards and [[Americans with Disabilities Act of 1990]] (ADA) improvements along connecting arterials.<ref name="SMARTtimeline"/>

===Major incidents===
On July 27, 1973, a [[station wagon]] traveling on the northbound span of the Silliman Evans Bridge in Nashville crashed through the bridge's guardrails, exited the roadway, and landed on the ground about {{convert|100|ft|m}} below, killing eight of the nine occupants and injuring the other.<ref>{{cite news |last1 = Gibson |first1 = Frank |last2 = Lewis |first2 = Dwight |date = July 28, 1973 |title = Long Drive, Fogged Road Spell Tragedy |url = https://www.newspapers.com/clip/70370910/long-drive-fogged-road-spell-tragedy/ |pages = 1, [https://www.newspapers.com/clip/70371507/overnight-drive-fog-spell-tragedy/ 13] |work = The Tennessean |location = Nashville |access-date = February 13, 2021 |via = Newspapers.com }}</ref> The accident was investigated by the [[National Transportation Safety Board]] (NTSB), which named a number of unsafe design features of the bridge as contributors to the crash. The report also concluded that the state had been aware of the safety hazards of the bridge's rails prior to the accident, which had played a role in previous fatal accidents on the bridge.<ref>{{cite news |last = Gillem |first = Tom |date = August 12, 1974 |title = State Knew Barrier Unsafe, Report Says |url = https://www.newspapers.com/clip/70379563/state-knew-barrier-unsafe-report-says/ |page = 1 |work = The Tennessean |location = Nashville |access-date = February 13, 2021 |via = Newspapers.com }}</ref><ref>{{cite news |date = August 14, 1974 |title = Bridge Information Needed |url = https://www.newspapers.com/clip/70380917/bridge-information-needed/ |page = 8 |work = The Tennessean |location = Nashville |access-date = February 13, 2021 |via = Newspapers.com }}</ref> This accident was cited as the primary event that led to the widening project on the bridge months later.

In 1979, structural problems were discovered on the Ohio River Bridge, including 119&nbsp;cracks as a result of defective welding in the tie girders.<ref>{{cite news |title = Bridge Jam to Continue over a Year |work = Williamson Daily News |date = August 30, 1979 }}{{page needed|date=June 2022}}</ref> The bridge was closed on August 3, 1979, and remained closed to all traffic through October 1980 and all truck traffic until mid-1981.<ref>{{cite news |title = Light Traffic Scheduled for I-24 Bridge by Oct. 1 |work = The Southeast Missourian |date = August 8, 1980 }}{{page needed|date=June 2022}}</ref>

On May 18, 2010, it was announced that a sinkhole was found in the eastbound lanes of I-24 in Grundy County near the exit to US&nbsp;64/SR&nbsp;50 (exit&nbsp;127). TDOT officials stated that the hole was growing and diverted traffic onto the westbound lanes.<ref>{{cite news |url = http://www.newschannel5.com/global/story.asp?s=12500016 |title = Sinkhole Forces I-24 Closure in Grundy County |location = Nashville, Tennessee |publisher = WTVF-TV |date = May 18, 2010 |access-date = May 18, 2010 |url-status = dead |archive-url = https://web.archive.org/web/20100522043722/https://www.newschannel5.com/global/story.asp?s=12500016 |archive-date = May 22, 2010 }}</ref> Following emergency repairs, the highway was reopened several days later.<ref>{{cite news |url = http://www.timesfreepress.com/news/2010/may/22/sinkhole-repaired-i-24-reopens/?local |title = Sinkhole Repaired, I-24 Reopens |work = Chattanooga Times Free Press |date = May 22, 2010 |access-date = June 26, 2010 |archive-date = March 18, 2012 |archive-url = https://web.archive.org/web/20120318055305/http://www.timesfreepress.com/news/2010/may/22/sinkhole-repaired-i-24-reopens/?local |url-status = live }}</ref>