The Minnesota Department of Transportation, Minnesota counties, and several local cities engaged WSB to help conduct a research report on the effectiveness of fog seal on chip sealed low volume roads. The objectives of this project are to determine the cost-effectiveness of fog seal over chip sealed roads, determine if fog sealing is a viable method for the prevention of loose rocks, and develop a best practice guide for agencies and contractors using this technique.
Chip seals have been widely used by agencies as a method of preventative maintenance to help prolong the life of suitable roads. However, there are issues surrounding the use of chip seals causing vehicle damage by loose rocks or being tracked onto private property. To address these concerns and improve the retention of chip seal aggregates, some agencies have incorporated the use of a fog seal. Data was gathered for this report through surveys of various agency and contractor experiences as well as research from other states. WSB surveyed municipalities, counties and cities for their feedback.
WSB’s expertise and in-depth data gathering will help guide communities on transportation decision-making across the state. The final report will be completed in April 2022.