Investigating the Environmental Costs of Deteriorating Road Conditions in South Africa

1. Investigating the Environmental Costs of Deteriorating Road Conditions in South Africa Contents L Mashoko, W L Bean, W JvdM STEYN

2. Contents Introduction and Background SA Road Network Methodology Results Conclusion and recommendations

3. Introduction and Background • Aim: to quantify the potential environmental costs of deteriorating road conditions in South Africa. • Road conditions have never been considered as a determinant of vehicle emissions (Bartholomeu and Filho (2008) . • Most studies use specific software to determine emissions based on default values from North America and European fleets.

4. Introduction and Background Past studies on effects of deteriorating road conditions in SA by Steyn and Bean. Some of the areas covered include: • Relationship between riding quality and truck maintenance and repair costs; • Relationship between riding quality and vehicle operating costs, and • Relationship between vehicle operating costs and road maintenance costs. • Affects of poor riding quality on cargo e.g agricultural produce.

5. Introduction and Background Source: Steyn and Bean, 2010

6. Introduction and Background Traffic characteristics • average speed, • types of vehicles, • number of lanes, • traffic volume In addition • the age of the vehicle, • the technology it represents, • its weight class • Load, speed and driving technique Vehicle Emissions

7. SA Road Network Condition Paved Road Network (SANRAL + Provinces) – 2013 Condition Source: SANRAL, 2013

8. Methodology GHG protocol- fuel-based or distance-based methodologies can be used to calculate CO2 emissions. Fuel based method chosen because fuel data is more reliable as opposed to activity data. Fuel based • UsesCO2 emission factor • Fuel consumption is multiplied by the emission factor. • Total Emissions Distance based • Distance based emission factors • Activity data- tkm or vehicle kilometres

9. Methodology Two set of calculations First Calculating GHG emission (kg/km) based on IRI values at speeds of 60, 80,100, 120 km/hr

10. Methodology Two Approaches Second • Comparing national road network to provincial road network. • Based on fuel consumption and fuel emission factors Source: Steyn and Bean, 2013 Difference =28 864 kL Emission factor used 2.70 kg per litre of fuel

11. Results Calculating GHG emission (kg/km)

12. Results GraphicalRepresentation

13. Results GHG Emission per km for SA Provinces

14. Results Comparison of Provincial and National Road Network

15. Results Other effects of deteriorating road conditions • Increased vehicle emissions when companies choose longer routes. • More materials are also required to maintain poor roads as they deteriorate faster than roads in good condition for the same traffic. • These two factors impact the environment negatively.

16. Conclusions • GHG emissions increase with an increase in speed and also with an increase in road roughness. • Although the increase is small for smaller increases in road roughness the analysis shows that the effect is very significant if the road conditions are very poor. • More fuel is consumed when travelling on provincial road network as compared to the national road network. • The increase in fuel consumed translates to an increase in GHG emissions (80 000 tonnes of carbon dioxide).

17. Recommendations • Empirical methods of data collection needed. • Trucks equipped with data collecting devices driven over different road network conditions. • This would mean that all the trucks in the experiment would have to travel in same conditions that is, the same load, same time for the trip, in the same weather conditions and the same drivers. • This was not possible in this study due to limited time and the costs involved in such an extensive study.

18. Thank you Name (lmashoko@csir.co.za)