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FHWA Home / Policy & Governmental Affairs / Highway Policy Information / Highway Statistics Series / 2020 / Table HM-47B - Highway Statistics 2020

Highway Statistics Series

Highway Statistics 2020


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NATIONAL HIGHWAY SYSTEM LENGTH - 2020
MILES BY MEASURED PAVEMENT ROUGHNESS - RURAL

NOVEMBER, 2020

Table HM-47B
(Sheet 1 of 2)
STATE INTERNATIONAL ROUGHNESS INDEX (IRI) (1)
INTERSTATE SYSTEM OTHER TOTAL
NOT REPORTED (2) < 95 95-170 > 170 TOTAL REPORTED NOT REPORTED (2) < 95 95-170 > 170 TOTAL REPORTED NOT REPORTED (2) < 95 95-170 > 170 TOTAL REPORTED
Alabama - 516 46 8 571 5 1,765 205 27 1,997 5 2,280 251 36 2,568
Alaska 20 566 321 94 982 322 277 225 165 667 342 843 546 260 1,648
Arizona 7 751 138 20 909 11 727 392 72 1,192 18 1,478 530 92 2,101
Arkansas - 360 67 12 439 - 1,167 649 122 1,938 - 1,527 716 134 2,377
California - 850 305 55 1,209 58 2,573 1,144 213 3,930 59 3,423 1,449 267 5,139
Colorado - 401 193 54 648 - 1,677 778 121 2,576 - 2,078 972 175 3,224
Connecticut - 27 2 - 29 - 93 57 7 157 - 120 59 8 186
Delaware - - - - - - 112 24 3 138 - 112 24 3 138
District of Columbia - - - - - - - - - - - - - - -
Florida - 699 17 1 717 3 2,379 364 18 2,762 3 3,079 381 20 3,479
Georgia - 482 52 5 538 - 2,653 557 35 3,245 - 3,135 608 40 3,784
Hawaii - - - - - 1 28 38 13 79 1 28 38 13 79
Idaho 2 463 46 11 519 7 1,315 288 92 1,695 9 1,778 334 103 2,214
Illinois - 1,106 121 17 1,243 - 1,334 877 198 2,408 - 2,440 998 214 3,652
Indiana - 648 100 21 769 - 1,398 318 29 1,745 - 2,046 417 51 2,514
Iowa - 497 104 9 610 34 2,075 1,086 230 3,392 34 2,573 1,190 239 4,002
Kansas - 557 78 5 640 1 2,709 285 38 3,031 1 3,265 362 42 3,670
Kentucky 1 653 52 6 710 6 1,255 350 33 1,638 7 1,908 402 38 2,348
Louisiana 3 326 184 16 527 4 562 458 104 1,125 6 889 642 120 1,651
Maine - 228 47 4 279 1 588 152 60 800 1 816 200 64 1,080
Maryland - 124 17 2 142 - 326 39 12 377 - 450 55 14 519
Massachusetts - 55 7 1 63 - 261 134 35 430 - 315 141 35 492
Michigan 4 436 105 17 558 - 1,949 471 63 2,483 4 2,385 576 80 3,041
Minnesota - 488 95 5 588 - 2,624 767 97 3,488 - 3,112 862 103 4,076
Mississippi - 513 57 9 578 - 1,265 477 70 1,812 - 1,778 534 78 2,391
Missouri - 786 51 5 842 - 2,476 481 44 3,001 - 3,262 532 48 3,843
Montana - 961 120 15 1,095 - 1,925 733 115 2,773 - 2,886 852 129 3,868
Nebraska - 366 46 3 415 1 2,025 539 118 2,682 1 2,390 586 121 3,096
Nevada - 442 13 1 457 - 1,374 156 14 1,544 - 1,816 170 15 2,001
New Hampshire - 135 6 1 142 - 310 59 18 387 - 445 65 18 529
New Jersey - 37 7 1 45 - 140 43 12 195 - 178 50 12 240
New Mexico - 701 119 24 843 - 1,272 407 70 1,749 - 1,973 525 94 2,593
New York 8 645 131 22 798 33 1,480 669 110 2,259 41 2,125 800 132 3,057
North Carolina 21 506 34 4 544 25 1,662 478 34 2,174 46 2,167 512 38 2,718
North Dakota - 481 26 2 510 - 2,452 416 77 2,945 - 2,933 442 79 3,455
Ohio - 544 85 14 643 1 1,449 401 43 1,893 2 1,993 486 57 2,536
Oklahoma 9 540 82 15 637 14 1,444 701 150 2,295 24 1,983 783 165 2,932
Oregon 2 436 54 3 494 4 1,967 612 75 2,653 6 2,403 666 78 3,146
Pennsylvania - 876 158 32 1,066 - 1,303 501 80 1,885 - 2,180 659 113 2,951
Rhode Island - 17 1 - 18 - 36 50 22 108 - 54 51 22 126
South Carolina - 490 51 5 546 4 1,081 450 58 1,589 4 1,571 501 63 2,135
South Dakota - 526 63 3 591 - 2,055 743 92 2,889 - 2,580 805 95 3,481
Tennessee - 608 32 4 645 11 1,401 288 38 1,728 11 2,010 320 43 2,373
Texas 1 1,688 287 25 2,000 17 5,519 1,936 166 7,621 18 7,207 2,223 190 9,621
Utah - 610 73 2 685 - 759 397 28 1,183 - 1,369 469 30 1,868
Vermont 1 233 19 3 255 - 229 62 17 307 1 462 81 20 562
Virginia - 539 57 2 598 - 1,208 519 34 1,760 - 1,747 575 36 2,358
Washington - 351 60 18 429 1 1,155 674 95 1,924 1 1,506 734 112 2,353
West Virginia - 265 43 11 319 7 526 402 84 1,013 7 791 446 95 1,332
Wisconsin 4 384 111 13 508 45 1,723 1,183 208 3,114 49 2,107 1,294 221 3,622
Wyoming - 697 97 13 807 54 1,445 441 29 1,914 54 2,142 538 41 2,721
U.S. Total 84 24,612 3,977 609 29,199 674 69,526 23,478 3,687 96,691 758 94,138 27,455 4,296 125,890
Puerto Rico 1 13 20 20 53 - 5 30 33 68 1 18 50 53 121
Grand Total 85 24,626 3,997 630 29,252 674 69,531 23,508 3,720 96,759 759 94,157 27,505 4,349 126,011

NATIONAL HIGHWAY SYSTEM LENGTH - 2020
MILES BY MEASURED PAVEMENT ROUGHNESS - URBAN

NOVEMBER, 2020

TABLE HM-47b SHEET 2 OF 2
STATE INTERNATIONAL ROUGHNESS INDEX (IRI) (1)
INTERSTATE SYSTEM OTHER TOTAL
NOT REPORTED (2) < 95 95-170 > 170 TOTAL REPORTED NOT REPORTED (2) < 95 95-170 > 170 TOTAL REPORTED NOT REPORTED (2) < 95 95-170 > 170 TOTAL REPORTED
Alabama - 344 66 22 433 13 944 268 64 1,277 14 1,288 335 86 1,709
Alaska - 63 14 1 78 1 82 59 19 161 1 145 73 21 239
Arizona 8 205 34 5 245 20 362 331 127 820 28 567 365 132 1,065
Arkansas - 223 72 16 310 - 284 260 134 678 - 507 332 150 989
California 4 651 476 117 1,243 381 1,287 2,523 3,765 7,575 385 1,937 2,999 3,881 8,818
Colorado - 172 112 20 304 - 512 582 285 1,380 - 684 694 305 1,683
Connecticut - 267 45 5 318 14 372 405 166 944 14 640 450 171 1,261
Delaware - 24 13 4 40 1 147 83 26 256 1 171 96 29 296
District of Columbia - 4 6 2 12 1 4 14 103 121 1 8 20 105 133
Florida - 672 94 12 778 7 3,074 1,202 266 4,542 7 3,746 1,295 279 5,320
Georgia - 602 97 10 709 - 1,863 707 176 2,747 - 2,465 805 186 3,456
Hawaii - 12 29 14 55 9 86 143 82 311 10 97 172 96 366
Idaho 1 80 10 2 92 2 157 63 36 255 3 237 73 37 347
Illinois - 722 174 45 942 2 972 1,376 808 3,156 2 1,695 1,550 853 4,098
Indiana - 354 117 21 492 5 437 196 48 682 5 791 313 69 1,173
Iowa - 126 43 8 178 21 300 410 209 919 21 426 453 217 1,096
Kansas 1 184 43 7 235 1 291 151 67 509 2 475 194 74 743
Kentucky 2 181 44 5 230 35 382 248 62 691 37 563 291 67 921
Louisiana 10 216 148 50 414 51 334 422 323 1,078 61 550 570 372 1,492
Maine - 76 9 1 87 12 63 55 30 148 12 140 64 31 235
Maryland - 257 55 23 336 6 630 367 314 1,311 6 887 423 337 1,647
Massachusetts 3 435 52 15 502 44 593 857 856 2,305 47 1,027 909 871 2,807
Michigan 3 436 184 52 673 36 828 1,093 777 2,699 39 1,265 1,277 830 3,371
Minnesota - 242 73 10 325 1 557 248 43 848 1 800 320 54 1,174
Mississippi - 208 37 8 253 - 437 376 184 997 - 645 413 192 1,250
Missouri - 442 79 16 538 - 750 423 175 1,347 - 1,192 502 192 1,886
Montana - 86 10 2 98 - 86 84 49 219 - 172 94 51 317
Nebraska - 47 19 3 69 3 122 159 180 461 3 169 178 183 530
Nevada - 114 44 4 162 - 229 142 49 419 - 343 185 53 581
New Hampshire - 81 2 - 83 - 211 74 34 319 - 292 76 34 402
New Jersey - 279 72 36 387 - 879 761 701 2,341 - 1,158 833 737 2,728
New Mexico - 125 26 6 156 - 167 143 70 380 - 292 168 75 536
New York 9 563 273 87 923 111 1,081 1,481 1,369 3,931 121 1,644 1,754 1,455 4,853
North Carolina 13 661 102 18 780 23 1,059 848 200 2,107 36 1,720 949 218 2,888
North Dakota - 53 7 1 61 1 87 80 38 205 1 140 88 38 266
Ohio 3 714 174 42 931 11 965 771 466 2,201 13 1,679 945 509 3,132
Oklahoma 2 204 65 15 284 14 315 246 90 651 17 519 311 105 935
Oregon 2 192 34 7 233 16 380 369 161 910 18 571 404 167 1,142
Pennsylvania - 581 167 49 797 4 1,126 1,459 829 3,414 4 1,708 1,626 877 4,211
Rhode Island - 46 5 1 52 6 81 147 190 418 6 127 152 191 470
South Carolina - 255 46 3 304 41 464 510 143 1,117 41 719 556 146 1,422
South Dakota - 67 20 1 88 2 49 71 35 154 2 116 90 36 242
Tennessee - 488 59 9 556 4 1,263 566 228 2,057 4 1,751 625 237 2,613
Texas 4 936 463 58 1,457 81 2,679 2,665 1,560 6,905 85 3,615 3,128 1,618 8,362
Utah - 184 63 7 253 - 401 240 56 697 - 584 303 63 950
Vermont - 58 6 1 64 2 46 29 12 87 2 104 35 13 151
Virginia - 402 105 13 521 - 698 786 280 1,765 - 1,100 891 294 2,285
Washington - 256 69 10 335 15 640 719 495 1,854 15 896 788 505 2,188
West Virginia 1 169 45 21 235 3 197 159 55 411 5 366 204 76 646
Wisconsin - 213 134 19 366 46 370 901 625 1,896 46 582 1,035 645 2,262
Wyoming - 70 29 7 106 3 87 63 27 177 3 157 92 34 282
U.S. Total 69 14,042 4,166 913 19,120 1,051 29,428 26,337 17,086 72,851 1,120 43,470 30,503 17,998 91,971
Puerto Rico 3 47 102 79 227 11 16 120 276 412 14 62 222 355 639
Grand Total 72 14,088 4,267 992 19,347 1,063 29,444 26,457 17,362 73,263 1,134 43,533 30,724 18,353 92,610
  1. Data are reported as the International Roughness Index (IRI) in inches per mile. Reference: World Bank Technical Paper Number 46, 1986. Lower IRI represents smoother
  2. May include sections entirely on structures and unpaved miles.
Page last modified on December 17, 2021
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000