Gravel Roads: Construction and Maintenance Guide

Full Description

This manual is mainly designed for the benefit of local agency officials, managers, an grader operators who are responsible for designing and maintaining gravel surfaced roads. The information provided in this manual is as nontechnical as possible without sacrificing clear guidelines and instructions on how to perform the operation well.

The U.S. Department of Transportation’s Bureau of Statistics reports 1.42 million miles of roads, or 35 percent of all roads in the United States remain unpaved as of 2012 (Source: Public Road and Street Mileage in the United States by Type of Surface – Table 1-4). In some nations, the road network is predominantly unpaved and generally consists of gravel roads. This manual was developed with a major emphasis on the maintenance of gravel surfaced roads, including some basic design elements.

Gravel roads are often considered to provide lower quality service than paved road surfaces. Yet, in many rural regions, the volume of traffic is so low that paving and maintaining a paved road is not economically feasible. Budget constraints are causing some agencies to revert failing paved surfaces to gravel surfaces. Consequently, understanding gravel road design, construction, and maintenance is very important.

In many cases, gravel roads exist to provide a means of transporting agricultural products in and out of farm fields, timber out of forests, or access to remote areas such as campgrounds and lakes. Many gravel roads serve rural residents as well. Many of these roads will remain unpaved due to very low traffic volume and/or lack of funds to adequately improve the sub- grade and base before applying pavement layer(s). In some countries, gravel roads are the only type of surfacing that can be provided, due to economic constraints.