These icons (
)
show footnotes as tooltips... for some browsers.
The Federal Aid Highway Act of 1968 authorized a 1500-mile increase in the
nation's Interstate Highway System, bringing the total to 42,500 miles.
(Such highways as I-129 in Iowa and I-27 in Texas were approved that year.)
In accordance with the Act, the Bureau of Public Roads asked the states to submit recommendations for where those 1500 miles should be located. The states' requests totaled more than 11,000 miles. As of April 1970, there were more than 9,400 miles of pending requests, with an estimated cost of over $13 billion.
This page lists those requests. Some ideas, like Arkansas' I-530, are interstates today. Others, like the US 78 corridor from Memphis to Birmingham, are still proposed. Still others seem too obscure to have ever had a chance.
There's some fun stuff: seeds of Charlotte's Outerbelt and other contemporary freeways; bits of "I-70 West" and other long-standing causes; and two northern New England interstates I call "I-92" and "I-98".
There are also three map scans related to the system and pending requests. These are large scans yet still hard to read, because of poor copy quality and small print size in the document. I recommend getting a road atlas to help identify roads and cities. On the maps, a circle around a city indicates one or more 3di's were approved or proposed there.
- System as of September, 1955 (huge)
- Additions in October 1957 (huge)
- Pending requests, March 30, 1970 (extremely big)
Source document: "Report on the Status of the Federal-Aid Highway Program", Hearing before the Subcommittee on Roads of the Committee on Public Works, U. S. Senate; dated April 15, 1970; pages 89-91.
Several road enthusiasts have contributed information about some proposals, including Steve Anderson (SA), Scott Kozel (SK), and Dan Moraseski (DM).
| State | Route | Miles | Comments |
| AL | Mobile Connector, I-65 to I-10 | 6.2 | now I-165 |
| AL | Birmingham toward Memphis | 91.3 | US 78 |
| AZ | Six urban routes in Phoenix | 63.3 | Loop 101 etc? |
| AZ | Three urban routes in Tucson | 31.0 | Hmmm.... |
| AR | Little Rock to Dumas | 77.3 | much of it is I-530 |
| AR | Little Rock to Newport | 79.0 | I-30 extension; once proposed as I-740 |
| AR | Gilmore to Walnut Ridge | 64.5 | future I-555 |
| AR | Van Buren to Rogers | 60.5 | much of it now I-540 |
| AR | Texarkana toward Shreveport | 33.5 | I-29/49 |
| CA | Fremont to Hayward | 15.2 | CA 238 upgrade. Ghost ramps at I-680 were torn down May 2002. |
| CA | San Bernardino west bypass, I-10 to I-15 | 14.2 | --- |
| CA | San Dimas (I-210) to CA 31 (now I-15) | 19.2 | CA 210 extension |
| CA | Sacramento toward Reno | 99.9 | US 50 ("I-70") |
| CA | SF Bay crossing and connectors | 24.9 | the "Southern Crossing" south of Bay Bridge |
| CA | Buttonwillow to Barstow via Bakersfield | 145.0 | CA 58 wants to be I-40 extension |
| C0 | Denver, NW quadrant of belt | 24.8 | Only part of C/E/W-470 not open or under const. |
| DE | Wilmington toward Norfolk | 79.0 | Delmarva interstate, called I-99 or I-101 in m.t.r. |
| FL | Miami to Homestead | 32.0 | I-95 extension |
| FL | West of Miami to Homestead AFB | 20.0 | I-95 extension 2? |
| GA | Macon connector, I-475 to I-16 | 8.0 | I-16 extension |
| GA | Augusta circumferential | 15.0 | part is now I-520 |
| GA | Savannah spur | 3.4 | I think this is I-516 |
| HI | Honolulu south loop | 6.5 | now H-1? |
| ID | Boise, east connector | 0.6 | --- |
| ID | McCammon (I-15) to Wyo. state line en route to I-80 | 87.0 | I-86 ext? |
| IL | DuPage Cty, I-55 to I-90 | 19.0 | now I-355 |
| IL | Hennepin to Peoria | 44.0 | "Heart of Illinois" expwy |
| IN | Indy, northeast expwy | 8.7 | --- |
| IN | Terre Haute to I-64 | 92.1 | US 41 |
| IN | Evansville to Ky. state line | 6.8 | --- |
| IN | Lake County, extend I-294 | 10.1 | ... to I-65 |
| IA | Cedar Falls to Mason City | 84.1 | US 218/18 |
| IA | Dubuque to Cedar Falls | 134.2 | US 20 |
| IA | Iowa City to Keokuk | 88.2 | US 218 |
| IA | Des Moines, southeast belt | 24.5 | now IA 5 |
| IA | Cedar Rapids, southwest to I-80 | 33.3 | US 151 |
| IA | Des Moines to Burlington | 151.6 | --- |
| IA | Sioux City to I-35 | 143.9 | US 20 |
| IA | Davenport to Dubuque | 66.3 | US 61 |
| IA | Independence diagonal route | 23.5 | --- |
| KS | K. C. to Ks., Mo., Okla. state lines | 138.7 | --- |
| KS | Wichita to Okla. state line en route to Tucumcari, NM | 216.7 | US 54 |
| KS | Wichita to Pittsburg | 144.6 | US 400 |
| KS | Olathe to Okla. state line en route to Tulsa | 157.4 | US 169 |
| KS | Belleville to Mo. state line en route to St. Joseph | 152.0 | US 36 |
| KS | Olivet (I-35) to Topeka | 41.5 | US 75 |
| KS | Ottawa to Lawrence (I-70) | 26.4 | US 59 |
| KS | Wichita, northeast belt | 10.0 | KS 96? |
| KY | Jefferson Fwy, Louisville | 34.7 | --- |
| KY | Crosstown Fwy, Lexington | 9.8 | --- |
| KY | Ind. state line to Henderson | 5.4 | --- |
| LA | New Orleans to Shreveport | 341.6 | Now I-49 |
| ME | Topsham to Brunswick | 3.8 | --- |
| ME | Bangor to Calais | 119.1 | "I-98" |
| ME | Augusta belt | 5.9 | --- |
| ME | Houlton to Van Buren | 77.5 | --- |
| ME | Pittsfield (I-95) to NH state line near Gilead | 94.8 | --- |
| MD | Balto - Wash. Parkway | 27.0 | MD 295 |
| MD | Baltimore to Annapolis | 20.5 | now I-97 |
| MD | Hancock (I-70) to Cumberland | 31.1 | now part of I-68 |
| MD | US 13, Norfolk - Wilmington route | 32.0 | MTR's real I-99 (or I-101) |
| MD | Annapolis to Del. state line en route to Dover | 45.0 | --- |
| MA | Haverhill, downtown connector | 2.0 | --- |
| MA | Beverly - Salem - Vinnin Square | 8.1 | --- |
| MA | Lawrence connector | 3.0 | --- |
| MA | Pittsfield to I-90 | 11.0 | US 7 |
| MA | Worcester - Fitchburg | 32.6 | now roughly I-190 |
| MI | Detroit inner loop | 9.0 | --- |
| MI | extend I-275 to I-75 | 21.0 | --- |
| MI | Flint to Port Huron | 60.0 | now I-69 |
| MI | Grand Rapids to Mackinaw City | 210.0 | US 131 |
| MI | Standish to Cheboygan | 184.0 | US 23 |
| MN | Duluth, extend I-35 | 5.4 | --- |
| MS | US 78, Birmingham to Memphis route | 120.3 | "I-22" according to some |
| MO | St. Louis, inner belt | 4.5 | route 755? |
| MO | Columbia via Jefferson City to Rolla | 86.3 | US 63 |
| NE | York (I-80) to Ks. state line en route to Salina | 57.2 | I-135 ext. |
| NE | I-80 spur to Grand Island | 6.9 | US 281 |
| NE | I-80 spur to Hastings | 16.9 | US 281 |
| NE | Lincoln to S. Sioux City | 120.8 | US 77 |
| NE | Omaha to North Bend | 42.6 | --- |
| NV | Reno to Carson City | 32.3 | future I-580 |
| NV | Las Vegas Spur | 10.5 | now part of I-515 |
| NV | Calif state line via Carson City to Utah line | 403.7 | I-70 ext. |
| NH | Southern state crossing (Albany - Portsmouth) | 103.0 | I-92? |
| NH | Midstate crossing (Glens Falls - Calais) | 44.0 | I-98? |
| NH | Manchester to Mass state line en route to Worcester | 31.0 | old Route 52 plan (I-190 ext.) |
| NJ | Newark, I-78 to I-280 | 3.0 | NJ 75 (DM) |
| NJ | Elizabeth to Newark | 6.0 | US 1-9? (DM) |
| NJ | Jersey City, I-78 to I-495 | 3.0 | NJ 85 (DM) |
| NJ | New Durham to Wayne | 35.1 | NJ 3 / US 46 (DM) |
| NJ | Delair (Pa. state line) to I-295 | 7.5 | NJ 90 (DM) |
| NJ | Bridgeport (Pa. state line) to I-295 | 4.0 | US 322 (DM) |
| NJ | Morristown to Springfield | 15.0 | The Matlock Expressway? (Simpsons in-joke) ... actually NJ 24 (I-278 ext.) (DM) |
| NJ | Franklin Lakes to NY state line near Alpine | 16.7 | --- |
| NJ | Hope to NY state line near Port Jervis | 34.0 | --- |
| NM | Las Cruces to Texico | 301.0 | "US 70: I-14?" |
| NY | Sheridan Expwy | 4.0 | I-895 (nee 278) ext. |
| NY | NYC, Co-op City Bypass | 2.9 | Possibly northern I-678 ext. along Hutch. Riv. Pkwy to I-95 at Bronx/Westchester line (SA) |
| NY | Binghamton to Rochester | 162.0 | sort of I-390 |
| NY | Buffalo to Pa. state line near Bradford | 64.4 | US 219 |
| NY | Binghamton - Erie | 150.5 | now I-86 |
| NY | Watertown - Burlington | 150.0 | NY 3, sort of |
| NY | Schenectady to Vermont state line en route to Portsmouth, NH | 26.1 | "I-92"; lower VT - NH crossing |
| NY | Syracuse north belt | 12.0 | -- |
| NY | Glens Falls to Vermont state line en route to Bangor | 33.0 | "I-98" |
| NY | Elmira - Courtland | 49.0 | NY 13 |
| NY | Rochester Outer Belt | 42.5 | -- |
| NY | Oyster Bay - Long Island expwys | 36.0 | LI Sound crossing; I-287 extension |
| NY | Binghamton - NYC | 132.0 | NY 17, mostly |
| NY | West Dutchess Expwy | 69.0 | -- |
| NY | Catskill Expwy | 60.5 | possible routing along US 209 from I-84 in Port Jervis to I-87 (I-587) in Kingston (SA) (but where's the Borscht Beltway?) |
| NY | Niagara Falls - Rochester | 66.3 | NY 18? close to once-proposed long 990 |
| NY | Lockport Expwy | 12.0 | I-990 |
| NY | Buffalo - Dansville | 61.0 | -- |
| NY | Yonkers - NJ expwy | 2.0 | -- |
| NY | Delaware - St Lawrence expwy | 212.0 | -- |
| NY | Amsterdam - Northway expwy | 20.0 | -- |
| NC | Asheville, north belt | 8.8 | -- |
| NC | Charlotte, outer belt and radial to outer belt | 71.5 | I-485 for the belt; radial = ? |
| NC | Winston - Salem to Greensboro (2 parts) | 42.8 | -- |
| NC | Greensboro spur (2 parts) | 7.6 | -- |
| NC | High Point to I-40 west of Greensboro (2 parts) | 13.0 | -- |
| NC | Durham, east connector to I-85 | 5.8 | -- |
| NC | Raleigh spur | 2.0 | -- |
| NC | Fayetteville, north and south bypasses | 25.0 | -- |
| NC | Greensboro to Wilmington | 159.0 | US 421; but predates I-40 ext. |
| NC | Morehead City spur | 83.0 | US 70 |
| NC | Asheville - Charlotte - Wilmington | 245.4 | US 74 |
| OH | Cleveland connector, I-71 to I-90 | 6.3 | -- |
| OH | Dayton west belt | 19.8 | -- |
| OH | Akron - Canton connectors | 67.2 | -- |
| OH | Toledo Connector, I-75 to I-280 | 3.6 | -- |
| OK | Okla City, spur to Will Rogers Airport | 2.2 | (never met a spur he didn't like) |
| OK | Tulsa to Tonkawa (at I-35) | 108.4 | -- |
| OK | Tulsa to Webbers Falls (at I-40) | 63.7 | -- |
| OR | Portland to Astoria (near Pac. coast) | 100.9 | Hyperextended I-505 |
| OR | Salem, extend I-305 | 2.3 | -- |
| OR | Eugene, extend I-105 | 4.2 | -- |
| PA | Ebensburg to NY state line en route to Buffalo | 115.0 | US 219 |
| PA | Harrisburg, West Shore Expwy | 6.0 | -- |
| PA | Allentown spur | 7.0 | I-178? |
| PA | Bethelehum spur | 4.0 | I-378? |
| PA | Wilkes-Barre spur | 2.5 | PA 309? |
| SC | Columbia, connector to I-26 | 1.5 | -- |
| SD | I-90 to Pierre | 34.5 | US 83 |
| TN | Memphis, Riverfront - NW Expwy | 8.9 | -- |
| TN | Chattanooga, Central Fwy | 8.6 | -- |
| TN | Dyersburg to Clarksville, I-155 to I-24 | 125.0 | -- |
| TN | Dyersburg to jackson, I-155 to I-40 | 40.0 | -- |
| TN | Memphis toward Birmingham, AL | 9.0 | US 78 |
| TX | Lubbock to Roscoe | 111.0 | I-27 ext. |
| UT | Salt Lake City, loop and radial | 12.5 | -- |
| UT | Lagoon (I-15) to Uintah Jct (I-84) | 10.9 | -- |
| UT | Green River to Spanish Fork | 126.4 | US 6 |
| VT | Southern state crossing (Albany - Portsmouth) | 45.2 | "I-92" |
| VT | Midstate crossing (Glens Falls - Calais) | 97.3 | "I-98" |
| VA | Richmond, extend I-195 to I-95 | 3.3 | probably the Downtown Expressway. (SK) |
| VA | Portsmouth - Norfolk connector | 8.0 | possibly the VA-164 Western Freeway and Midtown Tunnel (SK) |
| VA | Richmond, west belt | 30.0 | VA 288 (SK) |
| VA | Norfolk, extend I-464 to I-264 | 0.6 | the I-464 portion of the Downtown Tunnel / Berkley Bridge complex; 2.2 miles of I-264 wasn't added to the Interstate system until 1978. (SK) |
| WA | Tacoma, north loop | 10.6 | -- |
| WV | Weston (I-79) toward Stasburg, Va. | 128.1 | I-66 ext. |
| WI | Beloit to Milwaukee | 59.8 | now I-43 |
| WI | Milwaukee Belt | 40.7 | They'd be tearing it down by now |
| WI | Eau Claire to Superior | 151.7 | US 53 |