Where can I find information on gravel road maintenance?
As part of the network of LTAP Centers around the US, we share best practices and information. The South Dakota LTAP Center developed a Gravel Roads: Maintenance and Design Manual that is excellent for any gravel road in the US.
The Cornell Local Roads Program has a specification for a good gravel that can be used for your gravel roads.
The FHWA published the "Gravel Roads: Construction & Maintenance Guide" in 2015.