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Highway History

In 1998, with the Interstate System essentially complete, FHWA's Office of Engineering compiled information about development of the program. In making this information available to the public, we have not updated the material. All information is as of 1998 when the Office of Engineering compiled the report.

The Dwight D. Eisenhower System of Interstate and Defense Highways

Part VI - Interstate Status and Progress


Bulletin

Subject: Status of Development of the Dwight D. Eisenhower System of Interstate and Defense Highways as of December 31, 1997

Date: January 7, 1998


More than 99.9 percent, or 68,859 kilometers (42,787 miles), of the 68,871 kilometers (42,794 miles) Interstate System is now in use. Since December 31,1996,19 kilometers (12 miles) were put into service. Total kilometers now open to traffic includes 64,920 kilometers (40,339 miles) which are complete or essentially complete. The other 3,939 open kilometers (2,447 miles) include 146 kilometers (91 miles) requiring major improvements to bring them to full Interstate standards, 3,593 kilometers (2,232 miles) of toll facilities, and 200 kilometers (124 miles) currently under improvement or still requiring additional minor work to complete initial construction.

The status of the Interstate System as of December 31, 1997, is shown on the accompanying map and tables. Table I shows the status of improvements for each State. The following is a summary of this information:

 KilometersMilesPercent
Open to traffic
(Includes 3,593 kilometers or 2,232 miles of Toll Roads)
68,85942,78799.98
Under Basic Construction420.01
Engineering and Right-of-Way Acquisition850.01
Total68,87142,794100.0

Table II is a listing of the 12 kilometers (8 miles) not open to traffic which identifies in each State, the route and location of each section not open.


Dwight A. Horne
Chief, Federal-Aid and Design Division


English System

MILEAGE DESIGNATED UNDER SECTIONS 103(e)(1),(2), AND (3) OF TITLE 23 U.S.C.
StateNot Open to TrafficOpen to TrafficTotal Designated System**
Engr. or RowUnder Basic Constr.TotalTotal Facil.Adequate for Present TrafficMinor Work RemainingComplete or Essent. CompleteTotal
ALABAMA0.000.000.000.000.0020.20885.00905.20905.20
ARIZONA0.000.000.000.000.000.001,167.451,167.451,167.45
ARKANSAS0.000.000.000.000.000.00526.34526.34526.34
CALIFORNIA0.700.000.7010.000.0035.802,265.012,310.812,311.51
COLORADO0.000.000.000.000.000.00950.76950.76950.76
CONNECTICUT0.000.000.000.000.000.00291.04291.04291.04
DELAWARE0.000.000.0014.300.000.0026.3140.6140.61
DIST. OF COL.1.300.001.300.000.005.177.1812.3513.65
FLORIDA0.000.000.0086.660.000.001,373.531,460.191,460.19
GEORGIA0.000.000.000.000.000.001,200.861,200.861,200.86
HAWAII0.000.000.000.0012.260.0038.9651.2251.22
IDAHO0.000.000.000.000.000.00611.66611.66611.66
ILLINOIS0.000.000.00155.390.000.001,559.711,715.101,715.10
INDIANA0.000.000.00156.900.000.00979.651,136.551,136.55
IOWA0.000.000.000.000.000.00782.06782.06782.06
KANSAS0.000.000.00178.450.000.00642.73821.18821.18
KENTUCKY0.000.000.000.000.000.00740.54740.54740.54
LOUISIANA0.000.000.000.0015.753.16853.11872.02872.02
MAINE0.000.000.0054.480.000.00260.60315.08315.08
MARYLAND0.000.000.0020.1513.220.00357.17390.54390.54
MASSACHUSETTS0.002.402.40132.832.900.00323.98459.71462.11
MICHIGAN0.000.000.005.300.001.101,167.601,174.001,174.00
MINNESOTA0.000.000.000.000.000.00912.70912.70912.70
MISSISSIPPI0.000.000.000.000.000.00683.20683.20683.20
MISSOURI0.000.000.000.000.000.001,153.351,153.351,153.35
MONTANA0.000.000.000.000.000.001,187.541,187.541,187.54
NEBRASKA0.000.000.000.000.000.00481.48481.48481.48
NEVADA0.000.000.000.000.000.00543.44543.44543.44
NEW HAMPSHIRE0.000.000.0021.350.000.00197.66219.01219.01
NEW JERSEY0.000.000.0090.087.302.80321.65421.83421.83
NEW MEXICO0.000.000.000.000.000.00999.90999.90999.90
NEW YORK0.000.000.00478.780.900.00912.871,392.551,392.55
NORTH CAROLINA0.000.000.000.0012.920.71833.99847.62847.62
NORTH DAKOTA0.000.000.000.000.000.00571.19571.19571.19
OHIO1.600.101.70206.2017.140.001,305.351,528.691,530.39
OKLAHOMA0.000.000.00174.080.001.77632.80808.65808.65
OREGON0.000.000.000.000.000.00720.42720.42720.42
PENNSYLVANIA1.500.001.50360.330.0034.421,166.501,561.251,562.75
RHODE ISLAND0.000.000.000.000.000.0070.8270.8270.82
SOUTH CAROLINA0.000.000.000.000.006.41765.60772.01772.01
SOUTH DAKOTA0.000.000.000.000.000.00678.73678.73678.73
TENNESSEE0.000.000.000.006.800.001,030.101,036.901,036.90
TEXAS0.000.000.000.001.310.423,160.853,162.583,162.58
UTAH0.000.000.000.000.000.00941.32941.32941.32
VERMONT0.000.000.000.000.000.00320.44320.44320.44
VIRGINIA0.000.000.000.000.0012.501,052.841,065.341,065.34
WASHINGTON0.000.000.000.000.000.00763.85763.85763.85
WEST VIRGINIA0.000.000.0087.170.000.00427.94515.11515.11
WISCONSIN0.000.000.000.000.000.00578.09578.09578.09
WYOMING0.000.000.000.000.000.00913.61913.61913.61
TOTAL5.102.507.602,232.4590.50124.4640,339.4842,786.8942,794.49
PERCENT0.01%0.01%0.02%5.22%0.21%0.29%94.26%99.98%100.00%

Metric System

MILEAGE DESIGNATED UNDER SECTIONS 103(e)(1),(2), AND (3) OF TITLE 23 U.S.C.
StateNot Open to TrafficOpen to TrafficTotal Designated System**
Engr. or RowUnder Basic Constr.TotalTotal Facil.Adequate for Present TrafficMinor Work RemainingComplete or Essent. CompleteTotal
ALABAMA0.000.000.000.000.0032.511,424.271,456.781,456.78
ARIZONA0.000.000.000.000.000.001,878.831,878.831,878.83
ARKANSAS0.000.000.000.000.000.00847.06847.06847.06
CALIFORNIA1.130.001.1316.090.0057.613,645.183,718.893,720.01
COLORADO0.000.000.000.000.000.001,530.101,530.101,530.10
CONNECTICUT0.000.000.000.000.000.00468.38468.38468.38
DELAWARE0.000.000.0023.010.000.0042.3465.3665.36
DIST. OF COL.2.090.002.090.000.008.3211.5619.8821.97
FLORIDA0.000.000.00139.470.000.002,210.482,349.952,349.95
GEORGIA0.000.000.000.000.000.001,932.601,932.601,932.60
HAWAII0.000.000.000.0019.730.0062.7082.4382.43
IDAHO0.000.000.000.000.000.00984.37984.37984.37
ILLINOIS0.000.000.00250.080.000.002,510.112,760.192,760.19
INDIANA0.000.000.00252.510.000.001,576.591,829.101,829.10
IOWA0.000.000.000.000.000.001,258.601,258.601,258.60
KANSAS0.000.000.00287.190.000.001,034.371,321.561,321.56
KENTUCKY0.000.000.000.000.000.001,191.781,191.781,191.78
LOUISIANA0.000.000.000.0025.355.091,372.951,403.381,403.38
MAINE0.000.000.0087.680.000.00419.40507.07507.07
MARYLAND0.000.000.0032.4321.280.00574.81628.51628.51
MASSACHUSETTS0.003.863.86213.774.670.00521.40739.83743.69
MICHIGAN0.000.000.008.530.001.771,879.071,889.371,889.37
MINNESOTA0.000.000.000.000.000.001,468.851,468.851,468.85
MISSISSIPPI0.000.000.000.000.000.001,099.501,099.501,099.50
MISSOURI0.000.000.000.000.000.001,856.141,856.141,856.14
MONTANA0.000.000.000.000.000.001,911.161,911.161,911.16
NEBRASKA0.000.000.000.000.000.00774.87774.87774.87
NEVADA0.000.000.000.000.000.00874.58874.58874.58
NEW HAMPSHIRE0.000.000.0034.360.000.00318.10352.46352.46
NEW JERSEY0.000.000.00144.9711.754.51517.65678.87678.87
NEW MEXICO0.000.000.000.000.000.001,609.181,609.181,609.18
NEW YORK0.000.000.00770.521.450.001,469.122,241.092,241.09
NORTH CAROLINA0.000.000.000.0020.791.141,342.181,364.111,364.11
NORTH DAKOTA0.000.000.000.000.000.00919.24919.24919.24
OHIO2.570.162.74331.8527.580.002,100.762,460.192,462.92
OKLAHOMA0.000.000.00280.150.002.851,018.391,301.401,301.40
OREGON0.000.000.000.000.000.001,159.401,159.401,159.40
PENNSYLVANIA2.410.002.41579.890.0055.391,877.302,512.592,515.00
RHODE ISLAND0.000.000.000.000.000.00113.97113.97113.97
SOUTH CAROLINA0.000.000.000.000.0010.321,232.111,242.431,242.43
SOUTH DAKOTA0.000.000.000.000.000.001,092.311,092.311,092.31
TENNESSEE0.000.000.000.0010.940.001,657.791,668.731,668.73
TEXAS0.000.000.000.002.110.685,086.895,089.685,089.68
UTAH0.000.000.000.000.000.001,514.911,514.911,514.91
VERMONT0.000.000.000.000.000.00515.70515.70515.70
VIRGINIA0.000.000.000.000.0020.121,694.381,714.501,714.50
WASHINGTON0.000.000.000.000.000.001,229.301,229.301,229.30
WEST VIRGINIA0.000.000.00140.290.000.00688.70828.99828.99
WISCONSIN0.000.000.000.000.000.00930.35930.35930.35
WYOMING0.000.000.000.000.000.001,470.311,470.311,470.31
TOTAL8.214.0312.243,592.78145.65200.3064,920.1068,858.8268,871.06
PERCENT0.01%0.01%0.02%5.22%0.21%0.29%94.26%99.98%100.00%
Interstate Status

As of December 31, 1997, all but 7.60 miles of the 42,794-mile Interstate System as designated under Sections 103(e)(1), (2), or (3) of Title 23 were completed and open to traffic. The status of these 7.60 miles is shown in the following table:

Sections Not Open to Traffic, but Fully (or Partially) Under Construction As of December 31, 1997
Massachusetts2.40 milesI-90, Third Harbor Tunnel and approaches
Ohio0.10 milesI-670, Connector near downtown Columbus
 2.50 miles 
Sections Not Open to Traffic, and Not Under Construction as of December 31, 1997
California0.70 milesI-580 @ Alameda
Dist of Columbia1.30 milesI-295, Barney Circle Connector
Ohio1.60 milesI-670, Columbus Inner Connector
Pennsylvania1.50 milesI-95, Interchange with PA Turnpike
 5.10 miles 
Note: In addition to the 7.6 miles not open to traffic, there is some remaining Interstate Construction funded work not complete on sections already open to traffic. This work includes major upgradings, added lanes, stage construction, etc. and was reported in the 1991 Interstate Cost Estimate.
States With All Interstate System Mileage Open To Traffic As of December 31, 1997
Ranked by Date Opened To Traffic
(Based on FHWA PR-511 Records)
1Rhode Island6/75
2Nebraska11/76
3Delaware6/77
4North Dakota11/79
5Wisconsin6/82
6Arkansas12/82
7Vermont12/82
8South Dakota10/83
9New Mexico8/84
10Iowa9/85
11Wyoming10/85
12Nevada5/86
13Kentucky 9/86
14Maine 11/86
15Tennessee4/87
16Mississippi2/88
17Illinois8/88
18West Virginia8/88
19Montana9/88
20Missouri9/88
21New Hampshire11/88
22Oklahoma 4/89
23Georgia12/89
24Oregon12/89
25Kansas1/90
26Idaho6/90
27Maryland6/90
28Indiana 8/90
29Arizona 8/90
30Utah11/90
31Minnesota5/91
32Virginia6/92
33Connecticut6/92
34Texas 10/92
35North Carolina 10/92
36Washington 9/93
37Colorado9/93
38Florida 3/94
39Alabama10/94
40New Jersey12/94
41South Carolina8/95
42New York12/95
43Louisiana 5/96
44Michigan 7/97
45Hawaii12/97
MILEAGE DESIGNATED UNDER SECTIONS 103(e)(1),(2), AND (3) OF TITLE 23 U.S.C.
Calendar YearNot Open to TrafficOpen to TrafficTotal Designated System
Prelim StatusPE or R/WUnder Basic ConstrTotalToll RoadsAdequate for Present TrafficMinor Work RemainingComplete Non-TollTotal
19970.005.102.507.602,232.4590.50124.4640,339.4842,786.8942,794.49
19960.005.4014.1519.552,232.4595.11201.0840,246.3042,774.9442,794.49
19950.005.4024.9730.372,232.45100.88258.7540,172.0442,764.1242,794.49
19940.005.8039.6545.452,232.45107.23310.7040,098.6642,749.0442,794.49
19930.004.3049.8754.172,232.45145.71371.9739,991.2942,741.4242,795.59
19920.007.6796.26103.932,237.57160.51543.5639,750.0242,691.6642,795.59
19910.0021.13177.25198.382,236.87237.90699.3439,422.2842,596.3942,794.77
19900.0036.70226.41263.112,236.09323.29965.4239,007.1342,531.9342,795.04
19890.0056.29305.94362.232,236.09376.571,176.0838,647.5842,436.3242,798.55
19884.07295.44494.68794.192,268.34517.252,182.9437,035.6142,004.1442,798.33
19874.07367.57569.21940.852,226.30716.706,003.7332,912.1441,858.8742,799.72
19865.62480.17650.561,136.352,230.53851.1911,237.4727,342.1541,661.3442,797.69
1985134.47543.64737.971,416.082,242.94976.5311,930.9226,337.9741,488.3642,904.44
1984147.66637.78789.711,575.152,243.641,025.4613,235.3224,824.8741,329.2942,904.44
1983233.531,050.56629.211,913.302,197.801,044.7715,576.0522,165.1040,983.7242,897.02
1982320.581,112.53642.082,075.192,257.351,217.9625,608.5011,785.7840,869.5942,944.78
1981380.631,193.03735.662,309.322,265.801,231.4732,039.105,097.8340,634.2042,943.52
1980394.091,024.51828.842,247.442,262.941,417.6830,475.986,095.9640,252.5642,500.00
1979409.781,198.511,114.332,722.622,266.531,591.0229,787.746,132.0939,777.3842,500.00
1978469.891,394.391,223.513,087.792,266.121,686.2727,968.787,491.0439,412.2142,500.00
1977550.511,610.751,431.893,593.152,265.921,731.2726,149.638,760.0338,906.8542,500.00
1976676.481,800.431,840.744,317.652,266.301,940.0525,257.198,718.8138,182.3542,500.00
1975681.622,164.792,261.545,107.952,263.792,030.9224,002.269,095.0837,392.0542,500.00
1974837.172,659.712,730.596,227.472,308.172,093.5022,627.549,243.3236,272.5342,500.00
1973912.303,091.053,036.197,039.542,309.232,364.0030,787.2335,460.4642,500.00
19721,268.703,545.493,292.598,106.782,303.392,484.9729,604.8634,393.2242,500.00
19711,552.204,097.723,862.419,512.332,305.132,780.2027,902.3432,987.6742,500.00
19701,634.825,138.694,183.1110,956.622,306.072,932.4226,304.8931,543.3842,500.00
19691,780.736,299.094,782.4812,862.302,302.413,143.7624,191.5329,637.7042,500.00
19682,240.807,439.105,215.9014,895.802,303.303,109.9022,191.0027,604.2042,500.00
19671,062.908,805.005,490.2015,358.102,303.303,354.2019,984.4025,641.9041,000.00
19661,578.9010,292.105,653.4017,524.402,305.003,255.90 17,914 7023,475.6041,000.00
19652,878.9011,356.305,580.0019,815.202,318.502,893.9015,972.4021,184.8041,000.00
19644,680.8012,103.705,196.7021,981.202,324.803,058.9013,635.1019,018.8041,000.00
19637,435.1012,031.604,977.9024,444.602,347.103,077.8011,130.5016,555.4041,000.00
196211,368.1010,955.404,340.7026,664.202,307.303,113.808,914.7014,335.8041,000.00
196113,790.3010,668.004,245.3028,703.602,302.903,070.606,922.9012,296.4041,000.00
196016,402.4010,032.304,125.4030,560.102,263.703,041.005,135.2010,439.9041,000.00
1959         41,000.00
1958         41,000.00
1957   Mileage status data is not available for years prior to 1960. 37,700.00
1956         37,700.00
Pre-1956         37,700.00
Footnotes:
  • A reserve of undesignated mileage was reported in Preliminary Status through 1985; reporting discontinued thereafter.
  • No distinction was made between fully complete mileage and mileage with minor work remaining prior to 1974.
  • The designation of the first 37,700 miles of Interstate highways was announced by BPR on 8/2/47.
  • The Federal-Aid Highway Act of 1956 increased the system's proposed length to 41,000.
  • The Federal-Aid Highway Act of 1968 authorized the system's expansion to 42,500 miles.
  • Additional mileage (up to 500 miles) was added on 1/2/68 by P.L. 90-238, as amended, for making modifications or revisions as provided by 23 U.S.C. 103(e)(2) at no additional cost. [Howard-Cramer Additions]
Updated: 10/15/2013
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000