Roadway Management Toolbox: Gravel Mulch

What is This Treatment?

Gravel mulch involves the placement of loose evenly graded crushed or quarried rock on top of a geosynthetic fabric. The fabric prevents plants from rooting and the weight and porosity of the gravel keep the fabric in place and allow for percolation of water and air.

When to use This Design Concept?

Gravel mulch is best used as a vegetation control treatment in areas where disruption from errant vehicles is unlikely.

Benefits

• Installing gravel mulch is a low tech process that can be accomplished by any contractor and repaired by Maintenance crews with existing equipment.
• One of the least expensive control treatments available.
• Requires minimal maintenance and allows for infiltration of storm water into the soil.

Limitations

• Easily displaced by errant vehicles.
• Pore spaces fill with dirt and debris over time, may provide a growing medium for weeds.

Specifications and Details

• 2010 Standard Specification section 20-11, Gravel Mulch
• 2010 Standard Special Provision (SSP) 20-11, Gravel Mulch

Cost:

• $10 - $15/yd2 in areas beyond the gore and other flat areas
• $11 - $23/yd2 on side slopes
• BEES Item - none

Updated February 20, 2013