Road Safety Impact of Increased Rural Highway Speed Limits in British Columbia, Canada
Abstract
:1. Introduction
2. Methods
2.1. Overview
2.2. Data Sources
2.2.1. Fatal Crashes
2.2.2. Insurance Claims
2.2.3. Ambulance Dispatches
2.2.4. Gasoline Sales
2.2.5. Travel Speed
2.3. Mapping
2.4. Analysis
Analysis of Speed Data
3. Results
4. Discussion
4.1. Previous Evaluations of Speed Limit Changes
4.2. There Were More Crashes Following the Speed Limit Increases in British Columbia
4.3. Spillover
4.4. Travel Speed
5. Limitations
6. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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British Columbia | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
All Claims | Casualty Claims | Police Reported | Fatal Crashes | Ambulance Dispatches | Gas Sales (Billion L) | ||||||
Count (% Missing GIS Coordinates) | |||||||||||
Total | 4,242,998 | (29%) | 853,429 | (20%) | 625,988 | (21%) | 4,968 | (17%) | 375,163 | (7%) | 34.3 |
July 2000–June 2001 | 248,465 | (41%) | 53,437 | (28%) | 43,081 | (30%) | 344 | (22%) | |||
July 2001–June 2002 | 262,618 | (33%) | 53,684 | (23%) | 47,213 | (25%) | 382 | (17%) | |||
July 2002–June 2003 | 244,508 | (31%) | 52,880 | (22%) | 47,179 | (20%) | 387 | (13%) | |||
July 2003–June 2004 | 248,595 | (29%) | 52,305 | (21%) | 49,432 | (19%) | 403 | (12%) | |||
July 2004–June 2005 | 248,982 | (28%) | 52,049 | (19%) | 49,576 | (19%) | 402 | (14%) | 35,712 | (14%) | |
July 2005–June 2006 | 254,562 | (29%) | 52,589 | (20%) | 50,446 | (19%) | 395 | (14%) | 36,641 | (14%) | |
July 2006–June 2007 | 274,684 | (30%) | 52,158 | (20%) | 49,367 | (20%) | 343 | (15%) | 36,496 | (14%) | |
July 2007–June 2008 | 274,093 | (29%) | 52,028 | (20%) | 44,302 | (21%) | 354 | (13%) | 35,526 | (14%) | |
July 2008–June 2009 | 276,462 | (29%) | 49,729 | (20%) | 36,518 | (20%) | 309 | (14%) | 32,138 | (15%) | |
July 2009–June 2010 | 256,543 | (29%) | 50,642 | (19%) | 34,402 | (20%) | 345 | (18%) | 30,329 | (10%) | 4.80 |
July 2010–June 2011 | 259,966 | (30%) | 51,939 | (20%) | 35,229 | (20%) | 277 | (19%) | 27,845 | (0%) | 4.80 |
July 2011–June 2012 | 257,546 | (30%) | 53,091 | (20%) | 34,531 | (21%) | 269 | (29%) | 27,671 | (0%) | 4.66 |
July 2012–June 2013 | 260,569 | (29%) | 54,704 | (19%) | 34,880 | (20%) | 242 | (23%) | 27,223 | (0%) | 4.54 |
July 2013–June 2014 | 266,920 | (29%) | 54,294 | (21%) | 34,442 | (20%) | 245 | (24%) | 26,446 | (0%) | 4.60 |
Speed Intervention | |||||||||||
July 2014–June 2015 | 292,568 | (27%) | 57,214 | (21%) | 35,390 | (17%) | 271 | (20%) | 28,647 | (0%) | 5.17 |
July 2015–June 2016 | 315,917 | (22%) | 60,686 | (15%) | 30,489 | (0%) | 5.77 | ||||
Average | 265,187 | (30%) | 53,339 | (21%) | 41,733 | (21%) | 331 | (18%) | 31,264 | (7%) | 4.90 |
Affected 1 | Nearby 2 | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
All Claims | Casualty Claims | Police Reported | Fatal Crashes | Ambulance Dispatches | All Claims | Casualty Claims | Police Reported | Fatal Crashes | Ambulance Dispatches | |
Total | 23,772 | 5518 | 24,678 | 488 | 16,298 | 131,109 | 25,657 | 34,994 | 275 | 22,177 |
July 2000–June 2001 | 713 | 206 | 1543 | 43 | 4731 | 1251 | 1903 | 20 | ||
July 2001–June 2002 | 1053 | 253 | 1924 | 40 | 6642 | 1385 | 2367 | 22 | ||
July 2002–June 2003 | 1100 | 281 | 2001 | 42 | 6423 | 1462 | 2644 | 14 | ||
July 2003–June 2004 | 1214 | 337 | 2195 | 42 | 6733 | 1547 | 2776 | 14 | ||
July 2004–June 2005 | 1215 | 292 | 1982 | 39 | 827 | 7157 | 1617 | 2823 | 23 | 1856 |
July 2005–June 2006 | 1280 | 303 | 2139 | 46 | 940 | 7468 | 1646 | 2965 | 29 | 1943 |
July 2006–June 2007 | 1438 | 315 | 2176 | 39 | 1075 | 8286 | 1644 | 2902 | 14 | 2039 |
July 2007–June 2008 | 1696 | 387 | 1843 | 30 | 1164 | 8881 | 1651 | 2531 | 27 | 1981 |
July 2008–June 2009 | 1676 | 370 | 1527 | 27 | 1054 | 8979 | 1638 | 2224 | 22 | 1812 |
July 2009–June 2010 | 1460 | 341 | 1278 | 25 | 1089 | 8238 | 1620 | 1966 | 22 | 1859 |
July 2010–June 2011 | 1607 | 395 | 1401 | 30 | 1770 | 8417 | 1611 | 1985 | 14 | 1857 |
July 2011–June 2012 | 1445 | 322 | 1267 | 26 | 1568 | 8265 | 1583 | 1899 | 10 | 1700 |
July 2012–June 2013 | 1473 | 352 | 1136 | 7 | 1486 | 8467 | 1609 | 1930 | 19 | 1619 |
July 2013–June 2014 | 1728 | 396 | 1050 | 19 | 1575 | 9392 | 1668 | 1921 | 16 | 1654 |
Speed Intervention | ||||||||||
July 2014–June 2015 | 2122 | 443 | 1216 | 33 | 1720 | 10,817 | 1728 | 2158 | 9 | 1883 |
July 2015–June 2016 | 2552 | 525 | 2030 | 12,213 | 1997 | 1974 | ||||
Average | 1486 | 345 | 1645 | 33 | 1358 | 8194 | 1604 | 2333 | 18 | 1848 |
Estimate 1 (95% CI), p-Value | ||||||
---|---|---|---|---|---|---|
Affected 2 | Nearby 3 | BC | ||||
All claims 4 | 43.0 (16.0, 76.4), | 0.001 | 25.7 (16.1, 36.1) | <0.001 | 5.1 (−7.4, 19.3) | 0.444 |
Casualty claims 4 | 30.0 (9.5, 54.2), | 0.003 | 5.9 (−1.6, 14.0) | 0.128 | 4.8 (1.6, 8.1) | 0.003 |
Fatal crashes 4 | 118.0 (10.9, 225.1) | 0.031 | −46.7 (−115.6, 22.2) | 0.184 | 2.4 (−12.9, 20.3) | 0.774 |
Ambulance dispatches 5 | 8.8 (−7.0, 27.3) | 0.291 | 5.3 (−3.4, 14.8) | 0.242 | 4.5 (−0.9, 10.6) | 0.105 |
All Stations (n = 105) | Affected Stations (n = 16) | Non-Affected Stations (n = 89) | ||||
---|---|---|---|---|---|---|
Average hourly | Before | After | Before | After | Before | After |
Mean speed (kph) | 90.0 | 90.7 | 94.0 | 94.3 | 89.2 | 90.0 |
Median speed (kph) | 90.3 | 91.1 | 94.8 | 95.1 | 89.5 | 90.4 |
85th percentile speed (kph) | 100.4 | 101.3 | 104.7 | 105.3 | 99.6 | 100.6 |
Standard deviation speed (kph) | 11.4 | 11.5 | 11.6 | 11.9 | 11.3 | 11.5 |
Traffic volume | 397 | 406 | 237 | 250 | 425 | 434 |
Spring (March, April, May) | ||||||
Mean speed (kph) | 90.8 | 92.0 | 94.6 | 96.1 | 90.1 | 91.3 |
Median speed (kph) | 91.2 | 92.4 | 95.4 | 96.9 | 90.4 | 91.6 |
85th percentile speed (kph) | 101.2 | 102.6 | 105.3 | 106.9 | 100.4 | 101.8 |
Standard deviation speed (kph) | 11.3 | 11.5 | 11.5 | 11.8 | 11.2 | 11.4 |
Traffic volume | 392 | 408 | 227 | 245 | 422 | 437 |
Summer (June, July, August) | ||||||
Mean speed (kph) | 91.0 | 91.3 | 94.7 | 94.5 | 90.4 | 90.8 |
Median speed (kph) | 91.4 | 91.7 | 95.4 | 95.3 | 90.7 | 91.1 |
85th percentile speed (kph) | 101.6 | 102.1 | 105.5 | 105.5 | 100.8 | 101.5 |
Standard deviation speed (kph) | 11.3 | 11.5 | 11.5 | 11.9 | 11.3 | 11.4 |
Traffic volume | 444 | 450 | 300 | 315 | 470 | 474 |
Fall (September, October, November) | ||||||
Mean speed (kph) | 90.1 | 90.4 | 94.8 | 94.2 | 89.3 | 89.8 |
Median speed (kph) | 90.5 | 90.9 | 95.7 | 95.0 | 89.6 | 90.1 |
85th percentile speed (kph) | 100.6 | 101.1 | 105.5 | 105.2 | 99.7 | 100.4 |
Standard deviation speed (kph) | 11.4 | 11.6 | 11.6 | 12.0 | 11.4 | 11.5 |
Traffic volume | 400 | 399 | 226 | 234 | 431 | 429 |
Winter (December, January, February) | ||||||
Mean speed (kph) | 87.8 | 88.9 | 91.7 | 92.5 | 87.1 | 88.3 |
Median speed (kph) | 88.2 | 89.3 | 92.6 | 93.3 | 87.4 | 88.6 |
85th percentile speed (kph) | 98.2 | 99.5 | 102.7 | 103.5 | 97.4 | 98.7 |
Standard deviation speed (kph) | 11.5 | 11.6 | 11.9 | 12.0 | 11.4 | 11.5 |
Traffic volume | 351 | 367 | 196 | 206 | 379 | 395 |
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Share and Cite
Brubacher, J.R.; Chan, H.; Erdelyi, S.; Lovegrove, G.; Faghihi, F. Road Safety Impact of Increased Rural Highway Speed Limits in British Columbia, Canada. Sustainability 2018, 10, 3555. https://doi.org/10.3390/su10103555
Brubacher JR, Chan H, Erdelyi S, Lovegrove G, Faghihi F. Road Safety Impact of Increased Rural Highway Speed Limits in British Columbia, Canada. Sustainability. 2018; 10(10):3555. https://doi.org/10.3390/su10103555
Chicago/Turabian StyleBrubacher, Jeffrey R, Herbert Chan, Shannon Erdelyi, Gordon Lovegrove, and Farhad Faghihi. 2018. "Road Safety Impact of Increased Rural Highway Speed Limits in British Columbia, Canada" Sustainability 10, no. 10: 3555. https://doi.org/10.3390/su10103555
APA StyleBrubacher, J. R., Chan, H., Erdelyi, S., Lovegrove, G., & Faghihi, F. (2018). Road Safety Impact of Increased Rural Highway Speed Limits in British Columbia, Canada. Sustainability, 10(10), 3555. https://doi.org/10.3390/su10103555