Geospray® Culvert Outlet Washout Repair – Sterling Heights, MI



Water from a drainage tile and a culvert created a deep scour hole on the face of a 3 on 1 slope in the median of M-53 between the two bridges over the Clinton River in Sterling Heights, Michigan. The nearby maintenance garage believed that water leaking from the drainage tile near the top of the slope started the erosion. The erosion proceeded down toward the culvert, which was buried deeper down the slope.

The Michigan Department of Transportation (MDOT) decided to use Concrete Cloth CC8 to repair the site by creating a small chute. This spillway would channel water to the bottom of the slope, where a pile of riprap would slow the water flow and reduce further erosion.


Concrete Cloth GCCM was chosen for this site. MDOT used this project as a demonstration to learn how to install and manipulate the product.

On the first day of the installation, site preparation consisted of connecting the drainage tile to the culvert below with a new section of pipe. The scour hole was then filled and the slope was graded using an excavator. Stones and boulders that were found on the site during re-grading were separated for use later as riprap at the bottom of the new spillway to be constructed on day two.

Work began on day two by attaching an outlet structure to the end of the culvert. Concrete Cloth GCCM was attached to the outlet structure with screws, then the product was rolled down the slope and laid into the spillway that was graded earlier. The outside edges and the downslope end of the Concrete Cloth GCCM were buried and the downslope end was covered with riprap. Installation was completed within two hours, and hydration began using a water truck. The full project was completed within three hours.


The MDOT was satisfied with this demonstration project and is considering Concrete Cloth GCCM for another erosion control project in the near future.

Application: Culvert Outlet Washout Repair
Client: Michigan Department of Transportation
Location: Sterling Heights, MI
Installation: 2012

Deep scour hole created by water from drainage tile above.
Concrete Cloth GCCM material being hydrated.
Post-installation of Concrete Cloth GCCM.
One-year post installation of Concrete Cloth GCCM.
Site preparation prior to installation.
Concrete Cloth GCCM installed to channel water towards riprap.