What are the best practices for managing dust and erosion on gravel roads?

1 Why dust and erosion matter

Dust and erosion are not only nuisances for gravel road users, but also serious threats to the road's integrity and durability. Dust reduces visibility, increases maintenance costs, and harms human health and vegetation. Erosion washes away the road surface, creates ruts and potholes, and damages drainage structures and adjacent lands. Both dust and erosion reduce the road's load-bearing capacity, skid resistance, and ride quality, making it less safe and efficient for traffic.

3 How to prevent erosion

Erosion prevention is essential for gravel roads, especially in wet and steep conditions. To prevent erosion, the road shape should have a proper cross-slope and crown to facilitate water runoff and avoid ponding. The road edges should be well-defined and compacted to prevent lateral erosion and shoulder loss. Additionally, the road surface should be graded and raked regularly to remove loose material and fill depressions. The road drainage should be designed and maintained to divert water away from the road surface, with elements such as ditches, culverts, berms, and outlets that should be cleared of debris, vegetation, and sediment. To protect the road environment from erosion and sedimentation, revegetating disturbed areas, installing erosion control mats or geotextiles, applying mulch or straw, and constructing silt fences or check dams are all necessary measures.

4 How to monitor and evaluate

Monitoring and evaluating the performance of gravel roads is essential for identifying and addressing dust and erosion issues, as well as optimizing maintenance strategies and costs. This includes conducting regular inspections, measuring key indicators, and analyzing data and trends. Regular inspections should be visual assessments of the road's condition and functionality, using a checklist or rating system. Key indicators should be quantitative measurements of the road's characteristics and behavior, using instruments or tests. Data and trends should provide information on the road's performance, problems, and needs, as well as the effectiveness of the dust and erosion control methods. These results can then be used to support decision-making and planning for gravel road management.

5 How to learn more

If you are looking to gain more knowledge on the best practices for managing dust and erosion on gravel roads, the US Department of Transportation has created the Gravel Roads: Maintenance and Design Manual as a comprehensive guide. Additionally, the Minnesota Local Road Research Board has produced Dust Control on Unpaved Roads to provide a summary of best practices based on literature and case studies. Lastly, the Federal Highway Administration has created the Erosion Control Handbook for Local Roads which is a practical guide with principles, methods, and examples of erosion control practices.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?