Chapter 4: Road Network

Chapter 4: Road Network

Chapter 4: Road Network

1. Introduction

1.1 This chapter provides information about public road lengths by local authority, road class, type and speed limit. It also includes statistics on the amount of trunk road constructed/re-surfaced and information on the residual life of the trunk road network.

1.2. Unusual year to year changes in the reported road lengths may be due to the gradual introduction of Geographical Information Systems (GIS) to calculate road lengths by the data providers- see Notes and Definitions section, page 247.

Key Points

  • Scotland has 56,364 km of road network
  • Seven per cent is trunk road (1% is motorway)
  • Scotland has 10.4 km of road per 1,000 people compared to 6.2 km in GB.

2. Main Points

Road length

2.1 There were 56,364 kilometres of public road in Scotland at 31 March 2018. The trunk road network accounted for 7% of the total. Other (non-trunk) A roads represented 13% of the total.  Minor roads (B and C roads, and unclassified roads) accounted for the remaining 80% of roads.  (Table 4.1)

2.2 The length of the motorway network increased by 2% between April 2017 and April 2018.  (Table 4.1)

2.3 Over a quarter of the total trunk road network, and about one-seventh of the Scottish road network, is within the area of the Highland Council.  Around 10% of the Scottish road network is within the Aberdeenshire Council area and a further 8% is within the Dumfries and Galloway Council area.  These three Local Authorities account for almost a third of Scotland’s road network.  (Table 4.2)

Road Maintenance

2.4 Overall there was an increase of 24% in the amount of trunk road that was newly constructed, reconstructed, strengthened or surface dressed in 2017-18 compared to the previous year. (Table 4.3)

2.5 In 2017-18, 13.4% of the motorway network, 8.6% of the dual carriageway and 11.3% of the single carriageway trunk road network required close monitoring of the state of the road surface.  (Table 4.5 (b))

2.6 In 2017-18 the National Road Condition Indicator (RCI) showed 30% of the local authority A road network may, following more detailed examination, require some kind of maintenance (see the Notes and Definitions section, page 247). For the whole of the local authority network (all road categories), about 37% may similarly require some kind of maintenance. (Table 4.6)

Table 4.1: Public road lengths by class, type and speed limit 1, 2
2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017
Trunk roads 3, 6
Motorways Kilometres
Excluding slip roads 392 392 390 389 396 420 420 420 420 440 449
Including slip roads 547 547 546 544 558 599 599 600 601 632 645
A roads
Dual carriageway 521 521 523 523 511 500 500 504 504 505 510
Single carriageway 2,323 2,323 2,332 2,327 2,282 2,279 2,274 2,326 2,326 2,327 2,320
Other inc slips/roundabout 114 114 119 123 185 188 191 208 208 204 205
Total 2,958 2,958 2,974 2,974 2,978 2,968 2,966 3,037 3,037 3,036 3,036
by speed limit:
up to 40 mph 229 229 226 233 235 237 237 243 243 245 248
over 40 mph 2,730 2,730 2,748 2,740 3,302 3,330 3,328 3,395 3,395 3,424 3,433
All trunk roads 3,4 3,505 3,505 3,520 3,518 3,536 3,566 3,565 3,637 3,638 3,669 3,681
Local Authority major roads 7
Motorways
Excluding slip roads - - - - - - - - - - -
Including slip roads - - - - - - - - - - -
A roads
Dual carriageway 5 242 243 243 229 232 268 270 272 272 272 271
Single carriageway 5 7,139 7,178 7,178 7,185 7,235 7,204 7,203 7,134 7,142 7,146 7,156
Total 7,381 7,421 7,421 7,414 7,467 7,473 7,473 7,406 7,414 7,418 7,427
by speed limit:
up to 40 mph 1,491 1,515 1,508 1,509 1,559 1,567 1,572 1,616 1,621 1,630 1,642
over 40 mph 5,889 5,906 5,913 5,905 5,907 5,906 5,901 5,791 5,792 5,788 5,785
All LA major roads4 7,381 7,421 7,421 7,414 7,467 7,473 7,473 7,406 7,414 7,418 7,427
Local Authority minor roads 7
B roads
limit up to 40 mph 1,152 1,174 1,176 1,170 1,189 1,194 1,194 1,228 1,226 1,230 1,235
limit over 40 mph 6,349 6,292 6,318 6,311 6,310 6,309 6,305 6,270 6,276 6,268 6,255
Total 7,501 7,466 7,493 7,481 7,499 7,504 7,500 7,498 7,502 7,498 7,491
C roads
limit up to 40 mph 1,266 1,576 1,556 1,555 1,582 1,586 1,593 1,621 1,653 1,658 1,658
limit over 40 mph 9,104 9,091 9,102 9,098 9,105 9,104 9,098 9,060 9,051 9,045 9,043
Total 10,371 10,667 10,658 10,653 10,687 10,690 10,691 10,681 10,703 10,703 10,701
Unclassified roads
limit up to 40 mph 14,768 14,573 14,714 14,828 14,856 14,948 15,020 15,097 15,198 15,273 15,379
limit over 40 mph 11,661 11,712 11,726 11,732 11,727 11,732 11,728 11,735 11,696 11,688 11,686
Total 26,429 26,285 26,440 26,560 26,583 26,680 26,748 26,832 26,895 26,962 27,065
All LA minor roads 44,300 44,418 44,591 44,694 44,769 44,873 44,938 45,011 45,100 45,163 45,257
All roads (trunk and LA) 3
Motorways
Excluding slip roads 392 392 390 389 396 420 420 420 420 440 449
Including slip roads 547 547 546 544 558 599 599 600 601 632 645
A, B and C roads
Dual carriageway 5 763 764 766 752 742 768 770 776 775 776 781
Single carriageway 5 27,333 27,634 27,661 27,646 27,703 27,677 27,667 27,639 27,674 27,675 27,668
Total 28,210 28,512 28,546 28,522 28,630 28,633 28,629 28,623 28,656 28,656 28,654
by speed limit:
up to 40 mph 4,138 4,494 4,465 4,467 4,565 4,584 4,595 4,708 4,743 4,763 4,783
over 40 mph 24,073 24,019 24,081 24,054 24,624 24,648 24,632 24,515 24,515 24,525 24,516
Unclassified roads
limit up to 40 mph 14,768 14,573 14,714 14,828 14,856 14,948 15,020 15,097 15,198 15,273 15,379
limit over 40 mph 11,661 11,712 11,726 11,732 11,727 11,732 11,728 11,735 11,696 11,688 11,686
Total 26,429 26,285 26,440 26,560 26,583 26,680 26,748 26,832 26,895 26,962 27,065
All roads 3,4 55,186 55,344 55,532 55,626 55,772 55,912 55,975 56,054 56,152 56,250 56,364

Source: Transport Scotland - Not National Statistics
1. Motorway road lengths are derived from GIS from 2000 onwards - see commentary for more details.
2. Road lengths are physical length rather than carriageway length e.g. 10km of dual carriageway counts as 10km, not 20km.
3. These figures now include A road slip roads which have been excluded from the figures in previous publications. The time series has been updated to include this data resulting in an increase of 3-4% in Trunk road length and an increase in overall road length of 0.2%. The methodology for calculating the trunk road totals from the database has also changed resulting in some small changes to road lengths from those previously published.
4.Trunk road lengths for these roads have now been derived more accurately using a GIS system from 2006.
5. For 2008 and 2009 single and dual carriageways figures are estimated.
6. As at 30 May 2014.
7. Local authority road lengths at the end of the financial year e.g. 2013=2013/14.

Table 4.2: Public road lengths by council area and class, 2017/18
Council Trunk 3 Local Authority 2,5 Total
Motorway 1 Motorway slips A Roads Total A Roads B Roads C Roads Unclassified Total
kilometres
Aberdeen City - - 31 31 58 42 93 727 920 951
Aberdeenshire - - 192 192 687 799 1,540 2,504 5,529 5,722
Angus - - 53 53 193 255 489 878 1,814 1,867
Argyll & Bute - - 296 296 505 614 434 732 2,285 2,581
Clackmannanshire - - 3 3 49 34 28 179 291 294
Dumfries & Galloway 59 14 279 352 494 735 1,178 1,760 4,167 4,519
Dundee City - - 19 19 36 17 96 414 563 582
East Ayrshire 11 4 56 70 124 193 211 629 1,157 1,227
East Dunbartonshire - - 57 47 34 380 518 518
East Lothian - - 59 59 95 169 223 444 931 991
East Renfrewshire 9 3 10 22 31 50 83 319 483 505
Edinburgh, City of 19 14 34 67 135 51 119 1,111 1,417 1,484
Eilean Siar - - 340 177 189 486 1,191 1,191
Falkirk 39 13 5 58 114 96 118 650 979 1,036
Fife 20 9 96 124 322 325 352 1,428 2,426 2,551
Glasgow, City of 55 50 3 108 135 64 209 1,422 1,830 1,937
Highland - - 959 959 1,400 970 1,440 2,939 6,749 7,708
Inverclyde - - 28 28 24 23 54 270 370 398
Midlothian - - 39 39 93 100 101 392 686 725
Moray - - 98 98 157 296 366 737 1,556 1,654
North Ayrshire - - 68 68 101 155 207 574 1,036 1,104
North Lanarkshire 4 59 25 19 103 147 143 244 1,033 1,567 1,670
Orkney Islands - - 161 205 160 459 985 985
Perth & Kinross 39 14 209 261 435 367 638 1,055 2,496 2,757
Renfrewshire 18 10 26 55 65 62 140 557 824 879
Scottish Borders - - 167 167 459 599 769 1,148 2,975 3,142
Shetland Islands - - 225 162 199 464 1,049 1,049
South Ayrshire - - 93 93 108 209 232 625 1,173 1,266
South Lanarkshire 65 21 56 142 268 247 444 1,313 2,271 2,413
Stirling 21 6 116 144 212 161 170 473 1,017 1,160
West Dunbartonshire - - 23 23 46 8 27 297 378 401
West Lothian 35 13 - 47 152 117 116 666 1,052 1,099
Total 449 196 3,036 3,681 7,427 7,491 10,701 27,065 52,683 56,364
percentages
Aberdeen City - - 1.0 0.8 0.8 0.6 0.9 2.7 1.7 1.7
Aberdeenshire - - 6.3 5.2 9.3 10.7 14.4 9.3 10.5 10.2
Angus - - 1.8 1.4 2.6 3.4 4.6 3.2 3.4 3.3
Argyll & Bute - - 9.8 8.0 6.8 8.2 4.1 2.7 4.3 4.6
Clackmannanshire - - - 0.1 0.7 0.5 0.3 0.7 0.6 0.5
Dumfries & Galloway 13.2 7.4 9.2 9.6 6.7 9.8 11.0 6.5 7.9 8.0
Dundee City - - 0.6 0.5 0.5 0.2 0.9 1.5 1.1 1.0
East Ayrshire 2.4 1.9 1.8 1.9 1.7 2.6 2.0 2.3 2.2 2.2
East Dunbartonshire - - - 0.0 0.8 0.6 0.3 1.4 1.0 0.9
East Lothian - - 2.0 1.6 1.3 2.3 2.1 1.6 1.8 1.8
East Renfrewshire 2.1 1.4 0.3 0.6 0.4 0.7 0.8 1.2 0.9 0.9
Edinburgh, City of 4.2 7.2 1.1 1.8 1.8 0.7 1.1 4.1 2.7 2.6
Eilean Siar - - - 0.0 4.6 2.4 1.8 1.8 2.3 2.1
Falkirk 8.8 6.9 0.2 1.6 1.5 1.3 1.1 2.4 1.9 1.8
Fife 4.4 4.5 3.2 3.4 4.3 4.3 3.3 5.3 4.6 4.5
Glasgow, City of 12.2 25.5 0.1 2.9 1.8 0.9 2.0 5.3 3.5 3.4
Highland - - 31.6 26.1 18.9 12.9 13.5 10.9 12.8 13.7
Inverclyde - - 0.9 0.8 0.3 0.3 0.5 1.0 0.7 0.7
Midlothian - - 1.3 1.0 1.2 1.3 0.9 1.4 1.3 1.3
Moray - - 3.2 2.7 2.1 4.0 3.4 2.7 3.0 2.9
North Ayrshire - - 2.3 1.9 1.4 2.1 1.9 2.1 2.0 2.0
North Lanarkshire 13.2 12.9 0.6 2.8 2.0 1.9 2.3 3.8 3.0 3.0
Orkney Islands - - - 0.0 2.2 2.7 1.5 1.7 1.9 1.7
Perth & Kinross 8.6 6.9 6.9 7.1 5.9 4.9 6.0 3.9 4.7 4.9
Renfrewshire 4.1 5.3 0.9 1.5 0.9 0.8 1.3 2.1 1.6 1.6
Scottish Borders - - 5.5 4.5 6.2 8.0 7.2 4.2 5.6 5.6
Shetland Islands - - - 0.0 3.0 2.2 1.9 1.7 2.0 1.9
South Ayrshire - - 3.1 2.5 1.5 2.8 2.2 2.3 2.2 2.2
South Lanarkshire 14.5 10.5 1.9 3.9 3.6 3.3 4.1 4.8 4.3 4.3
Stirling 4.8 3.2 3.8 3.9 2.9 2.1 1.6 1.7 1.9 2.1
West Dunbartonshire - - 0.7 0.6 0.6 0.1 0.3 1.1 0.7 0.7
West Lothian 7.7 6.5 - 1.3 2.0 1.6 1.1 2.5 2.0 2.0
Total 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0

Source: Transport Scotland - Not National Statistics
1. Motorway road lengths have been consolidated using a GIS system which means that there will be some changes to previously published figures.
2. Triangulation with other sources of road length data has occurred to improve the quality of the information. Figures may not be comparable with previous editions.
3. As at 30 May 2016.
4. The drop in the length of trunk A roads from last year is probably due to  the detrunking of A80 with the opening of the M80.
5. Local authority road lengths at the end of the financial year.

Table 4.3: Trunk road constructed/re-surfaced etc
  2007-08 2008-09 2009-10 2010-11 2011-12 2012-13 2013-14 2014-15 2015-16 2016-17 2017-18 (prov)
Equivalent road lane length lane-kilometres (estimated)
New roads
constructed/opened - 58 - 52 132 - 18 3 3 0.5 86
Reconstructed 80 56 51 27 57 1 9 7 - 1 -
Strengthened 170 194 213 239 168 338 360 365 367 428 457
Surface dressed 79 123 30 35 10 21 11 14 8 29 24
Total 329 431 294 353 367 360 398 389 378 459 567
Percentages of total percentages
New roads
constructed/opened - 13 - 15 36 - 5 1 1 0 15
Reconstructed 1 24 13 17 8 16 0 2 2 - 0 -
Strengthened 52 45 72 68 46 94 90 94 97 93 81
Surface dressed 24 29 10 10 3 6 3 4 2 6 4
Total 100 100 100 100 100 100 100 100 100 100 100

Source: Transport Scotland - Not National Statistics

Table 4.4 (a): Trunk road constructed/re-surfaced etc, by unit, 2016-17
Unit New road constructed for traffic Reconstructed Strengthened Surface Dressed Total
Equivalent road lane length lane-kilometres (estimated)
NW - - 137 11 148
NE 0.5 1 60 3 65
SW - - 84 5 89
SE - - 144 10 154
FBOC - - 3 - 3
Total 0.5 1 428 29 459
Percentages of total percentages
NW - - 32 38 32
NE 100 100 14 10 14
SW - - 20 17 19
SE - - 34 34 34
FBOC - - 1 - 1
Total 100 100 100 100 100

Source: Transport Scotland - Not National Statistics

Table 4.4 (b): Trunk road constructed/re-surfaced etc, by unit, 2017-18 (provisional)
Unit New road constructed for traffic Reconstructed Strengthened Surface Dressed Total
Equivalent road lane length lane-kilometres (estimated)
NW - - 155 6 161
NE 30 - 70 9 110
SW 1 56 - 113 4 172
SE 1 - - 115 6 121
FBOC - - 3 0 3
Total 86 - 457 24 567
Percentages of total percentages
NW - - 34 23 28
NE 35 - 15 37 19
SW 65 - 25 16 30
SE - - 25 25 21
FBOC - - 1 - 1
Total 100 - 100 100 100

Source: Transport Scotland - Not National Statistics

Table 4.5: Trunk road network: Residual Life1 (years)
(a) Residual Life of Pavements (i.e. road surface) as percentage of whole network
Residual Life (years)
<0 0-4 5-9 10-14 15-19 >19
percentages
1997-98 11 8 11 8 8 54
1998-99 10 9 9 8 7 57
1999-00 10 8 10 9 10 53
2000-01 9 7 9 8 8 59
2001-02 4 4 7 7 10 68
2002-03 4 4 7 7 11 67
2003-04 4 4 6 7 12 67
2004-05 4 5 6 7 13 65
2005-06 4 4 6 7 15 63
2006-07 5 4 6 7 15 63
2007-08 4 4 7 7 13 65
2008-09 4 4 6 7 11 68
2009-10 5 5 7 8 11 64
2010-11 5 4 6 7 9 69
2011-122 10 7 10 10 11 52
2012-13 13 8 10 10 12 46
2013-14 14 8 10 9 11 49
2014-15 13 7 9 9 12 50
2015-16 12 9 9 9 13 48
2016-174 12 9 9 9 12 49
2017-184 11 9 9 9 12 51
Operating Company Areas 2017-18 4
Forth Bridges Unit 16 7 8 6 14 47
North West Unit 11 8 8 8 12 53
North East Unit 14 11 12 11 12 41
South East Unit 9 9 10 9 12 52
South West Unit 9 8 8 7 12 57

 

(b) The proportion of the motorway/dual and single carriageway trunk road network, which require close monitoring 3
  Motorways Dual carriageways Single carriageways
Requires close monitoring Requires close monitoring Requires close monitoring
% % %
2002-03 7.5 5.2
2003-04 9.0 5.1
2004-05 9.2 3.9
2005-06 6.7 3.2
2006-07 6.1 2.7
2007-08 8.2 3.9
2008-09 4.3 4.1
2009-10 6.3 5.5 3.7
2010-11 6.2 3.4 4.2
2011-122 12.9 9.1 10.3
2012-13 23.1 13.3 11.6
2013-14 23.4 15.0 10.3
2014-15 22.9 10.4 11.3
2015-16 21.5 9.8 10.5
2016-174 16.9 10.7 11.5
2017-184 13.4 8.6 11.3
Operating Company Areas 2017-18 4
Forth Bridges Unit 17.7 8.8 -
North West Unit - 10.5 11.5
North East Unit 14 8.6 20.5
South East Unit 16.5 6.2 4.7
South West Unit 9.19 9.1 9.7

Source: Transport Scotland - Not National Statistics
1. Residual life represents the number of years to elapse before the pavement reaches the stage when it may be necessary to undertake relatively more expensive reconstruction rather than strengthening to restore its full life.
2 Method of calculation changed in 2011-12.
3. The part of the network that requires close monitoring is that which has a residual life of less than zero.
Note: it has been decided that surveyed network length is not required as the figures produced are now representative of the whole network as shown in Table 4.1
4. These figures are provisional.

Table 4.6: Local authority road network condition 1, 2
A roads B roads C roads Unclassified All roads
Condition Condition Condition Condition Condition
Red Amber Red Amber Red Amber Red Amber Red Amber
(a) in each Council area: 2017-18 percentage
Aberdeen City 3 20 3 19 5 22 5 26 5 25
Aberdeenshire 3 23 2 22 2 20 4 25 3 23
Angus 2 22 5 31 5 26 6 27 5 27
Argyll & Bute 9 35 22 42 20 42 16 37 17 39
Clackmannanshire 2 23 3 26 4 26 8 34 6 30
Dumfries & Galloway 5 29 6 30 11 36 17 39 12 36
Dundee City 2 14 1 16 1 13 4 26 3 22
East Ayrshire 2 17 6 30 8 32 11 33 8 31
East Dunbartonshire 4 24 4 26 3 23 7 31 6 29
East Lothian 3 26 6 34 4 29 5 29 5 30
East Renfrewshire 2 15 4 28 8 26 9 33 8 30
Edinburgh, City of 4 23 2 18 4 26 7 32 6 30
Eilean Siar 7 29 5 32 7 42 8 40 7 36
Falkirk 3 26 7 35 6 34 5 32 5 32
Fife 4 26 5 29 3 26 4 29 4 28
Glasgow, City of 3 25 2 20 2 18 5 28 4 26
Highland 4 25 6 29 9 31 12 32 9 30
Inverclyde 3 21 5 31 8 32 8 31 7 31
Midlothian 3 22 4 27 4 29 5 30 5 28
Moray 3 23 2 21 3 22 5 27 4 24
North Ayrshire 8 28 6 33 13 38 6 29 8 32
North Lanarkshire 2 18 3 21 3 24 6 32 5 28
Orkney Islands 2 20 3 18 2 14 1 19 2 18
Perth & Kinross 7 32 7 34 6 32 5 30 6 31
Renfrewshire 3 21 3 23 8 29 6 29 6 28
Scottish Borders 6 32 9 38 8 36 14 43 10 38
Shetland Islands 1 17 6 28 3 28 8 38 5 30
South Ayrshire 6 32 8 33 8 33 8 33 8 33
South Lanarkshire 3 20 3 22 5 32 5 28 4 27
Stirling 4 26 7 33 9 33 15 35 10 32
West Dunbartonshire 3 24 1 17 4 26 5 29 4 27
West Lothian 2 19 4 27 9 36 3 25 4 26
Scotland 4 26 6 29 7 29 8 31 7 30
(b) for Scotland as a whole: 2005-06 to 2017-18 (New RCI Series) 2
2005-06 4 27 4 28 4 31 .. .. .. ..
2006-07 4 29 4 29 4 32 .. .. .. ..
2007-08 5 29 6 34 5 33 .. .. .. ..
2008-09 5 28 5 34 5 33 7 37 6 34
2009-10 6 30 6 35 5 33 8 39 7 36
2010-11 6 30 7 36 7 35 10 42 8 38
2011-12 6 30 8 36 8 36 8 38 8 36
2012-13 5 24 7 28 7 28 9 30 7 29
2013-14 5 24 7 28 8 28 9 30 8 29
2014-15 5 24 7 29 9 29 9 30 8 29
2015-16 4 25 6 29 6 28 9 31 7 29
2016-17 4 25 6 29 6 28 9 31 7 29
2017-18 4 26 6 29 7 29 8 31 7 30
(b) for Scotland as a whole: 2002-03 3 to 2007-08 (Old SPI Series)
2002-03 4 9 37 .. .. .. .. .. .. .. ..
2003-04 7 33 12 45 8 37 18 52 13 45
2004-05 5 6 31 10 43 5 31 15 50 11 42
2005-06 6 31 9 40 4 29 14 51 10 42
2006-07 6 34 11 35 5 29 18 57 13 47
2007-08 6 34 10 46 6 36 16 53 12 46

Source: Scottish Road Maintenance Condition Survey - Not National Statistics
1. From 2007-08 the basis of the statutory road performance indicator in Scotland changed to the UK Standard RCI.
2. While it has been possible, following the change to the indicator, to calculate the equivalent RCI value for all classified roads from 2005-06, it has not been possible to do this in a reliable manner for unclassified roads, owing to a lack of cracking data for those years. As unclassified roads represent a significant part of the total road network, RCI data for the network is similarly not available for this period. It is important to note that owing to the different formulation, no valid comparison can or should be made between the two series
3. The categories used to indicate the condition of the road are in brief:
amber - further investigation should be undertaken to establish if treatment is required
red - the road has deteriorated to the point at which it is likely repairs to prolong its future life should be undertaken.
4. Information for 2002-03 is available only for A roads.
5. The SPI figures for Scotland in 2004-05 exclude Glasgow, as the survey in Glasgow was undertaken on a different basis in that year.