Project Overview
The Boone Street drainage channel periodically overflows during storm events, overtopping the recently constructed concrete channel. The earth slopes above the concrete walls were prone to erosion. The City of Olney, IL had tried turf reinforcement mats placed on the steep slopes above the cast-in-place concrete channel section with little success. Grass grew non-uniformly and the turf reinforcement mat had large wrinkles in it. Not only was the section unsightly, it made mowing impossible by nearby residents, and did not provide the erosion protection the city wanted.
The city decided to place CC GCCM in a small trial area to see how it would perform. On October 13th, 2011 the first section was installed. Based upon the positive experience with the first section, the city installed more ditch lining on September 5th, 2012.
Solution
Combat Concrete was chosen and an initial test section was installed in 2011. The following spring, the test section was evaluated and judged effective. The next section of the channel was installed in September of 2012.
2011: Before the installation of Combat Concrete (CC) GCCM, the area was graded smooth. The CC GCCM material was put into a small anchor trench at the top of the slope and was tucked behind the vertical wall of the U-shaped ditch channel. At the existing culvert inlet, CC GCCM was capable of conforming to the complex geometry of the grouted rip rap headwall. After being placed in a groove cut with a power tool, the groove was grouted with a cement grout.
2012: The trial section was still in excellent condition. The city began work on the left side of the ditch section upstream of the trial section. The trial section is farther downstream on the right side. Note, the right side will not be addressed at this time. In order to prevent floating debris from being deposited on the top of the u-shaped channel, Combat Concrete GCCM was placed in a groove and grouted.