Multi-use trails have become an essential part of urban living. Here in Indianapolis, we have the popular Monon Rail Trail, which intersects the city and stretches all the way to Westfield in the north. These facilities allow easy public access to green spaces and promote physical activity and alternative modes of transportation, such as running and biking.

One of the challenges of constructing these trails is choosing the right surface materials to meet a variety of needs and locations: gravel, concrete or asphalt? In fact, multiple surface materials may be necessary for one trail. In this blog post, we go over the advantages and disadvantages of each material.

Gravel

Gravel is a common choice for rural nature paths for three key reasons: it fits in aesthetically with natural surroundings, it minimally disrupts the environment and it is affordable to install. All these factors make gravel an appealing choice for a trail.
However, gravel also presents some serious drawbacks. The surface quality is difficult to maintain, and the material is susceptible to erosion. And although gravel offers lower impact on runners’ and walkers’ joints, the material is not ideal for multi-use. Loose gravel is unstable and challenging for both runners and bikers, and it can be difficult to meet ADA surface standards with a gravel surface.

Concrete

Concrete presents two chief advantages as a paving material for multi-use trails: longevity and minimal maintenance. A concrete path could last up to 50-70 years with minimal maintenance. The surface will stand up to corrosion and remain consistent overtime.
A major drawback of using concrete is that the initial installation is more expensive than other materials. In addition, concrete is harder on runners’ and walkers’ joints. Finally, concrete does not have the softer aesthetic look of gravel; it is more industrial and disruptive.

Asphalt

Asphalt arguably offers the best initial surface for a multi-use trail. It is smooth, free from cracks and bumps, soft on joints and easily adheres to ADA requirements. As a porous material, it facilitates water runoff. Asphalt is less expensive to install than concrete and offers greater longevity than gravel.
The downside to asphalt as surface material is its maintenance requirements. Asphalt can crack and disintegrate over time. Regular sealing and maintenance extends its life for 25-45 years, but it must be regularly maintained.

In many ways, asphalt is the perfect middle ground between gravel and concrete and the most effective use of your budget. However, the appropriate surface materials for your multi-use trail depend on the specific needs and environment of your urban project.