Mobile Irrigation Lab
Row Arrangement
Winter Road Seeding
Vegetated Treatment
Systems
Grade Stabilization
Water & Sediment Basins
Filter Strip
Hedgerow
Streambank Protection
Underground Outlets
Vegetated Waterways
Livestock & Land Program

Definition

Grade stabilization structures are used to control the grade and head cutting in earthen channels.

Purpose:

To safely convey water from the top of a headcut to a stable outlet for maximum grade stabilization structural integrity.

Criteria:

The structure must be designed for stability. The outlet must be designed and built to prevent damage to the structure, or downstream areas.

*This is not intended as a how to guide. Individual practices must meet minimum standards and comply with local laws and regulations. For more information contact your local RCD or NRCS office.

Gully Head Cut

Repaired landscape after grade stabilization structure installation

Gully erosion is a major problem for many of our hillside farmers. We help cooperators solve gully erosion by reducing stormwater runoff and using underground pipes or channels lined with vegetation to convey stormwater off site. In settings with high flow rates, highly erodible soils and high sediment loads, these measures are sometimes inadequate. Pipes may fill with sediment, and vegetated channel linings may fail. Traditional methods of stabilizing gullies with rock or concrete structures can be very expensive.

The RCD is experimenting with soil cement grade stabilization structures. Soil cement is a mixture of sandy soil excavated on site with portland cement. The mixture is compacted in place like earth fill and over time hardens to the consistency of sandstone.

At our pilot project site, the structures are performing well one year after installation. This was the heaviest winter in five years, and the site is performing as expected. The gully there was stabilized for half the cost of using rock or concrete. We are monitoring the site for stability and durability. Please note: these structures should be designed by a qualified engineer. Contact the RCD if you have any questions.

This rapidly eroding gully adjacent to a farm road was stabilized by an innovative technique developed by RCD staff utilizing onsite materials to construct soil cement grade control structures.

Following the winter rains, the effectiveness of the soil cement grade control structures is readily visible in this photo.

In order to arrest gully erosion at sites with relatively stable banks, we are experimenting with brush packing. This consists of placing layers of brush – willow or coyote brush – across the bed of the gully. After sediment is trapped to bury that layer of brush, a new layer can be placed on top to capture more sediment.

The materials cost is very low, but the labor requirements are high. These structures are very prone to failure if built incorrectly or applied in an inappropriate setting. Please contact the RCD for more information.

Downcutting in this gully was stabilized  with the construction of a series of brush mats, a biotechnical alternative for gully stabilization.