Transportation Defined: Minibenches

No, the stair-step design on the slope at right isn’t just for looks…

The “steps” are actually referred to as minibenches and they serve as an erosion and sediment control measure on slopes like the one in the photo (that happens to be the I-10 Marsh Station project, in case you were wondering).

Minibenches are designed to retain soil on slopes that may otherwise be susceptible to erosion due to weather.

They also improve water infiltration and basically work to increase the effectiveness of other temporary or permanent soil stabilization efforts.

How are they made?

They’re created with heavy-duty equipment. The minibenches on the I-10 Marsh Station project were made with an excavator that was used to “dig” out the benches starting from the top of the slope down. Those particular minibenches will get wattles, which will assist in keeping the slopes from eroding. They'll also get seeded in another effort to achieve final stabilization of the slopes.

A closer look at minibenches.

When are minibenches used?

Minibenching can be implemented on projects in areas that have soils prone to erosion.

Minibenching is also considered in cases where there’s a large, engineered slope that needs to be created or if there’s a particularly steep slope on a project.

Transportation Defined is a series of explanatory blog posts designed to define the things you see on your everyday commute. Let us know if there's something you'd like to see explained ... leave a comment here on the blog or over on our Facebook page!