A tributary of Clark Creek, prone to frequent flooding that has overtopped Holly Bush Road and affected nearby properties, has been identified for drainage improvements under Rankin County’s American Rescue Plan Act (ARPA). The project has aimed to reduce flood risks and enhance hydraulic capacity through a hybrid approach that combines structural measures with environmentally friendly, nature-based solutions.
The restoration includes 3,000 linear feet (LF) of channel improvements, with permit restrictions limiting work within the Ordinary High-Water Mark (OHWM) to 999 LF. The design strategically allocates the allowable 999 LF of in-channel improvements to sections most in need, including 50 LF of riprap just downstream of Holly Bush Road and 120 LF of riprap along steeper banks constrained by existing fences. To manage high flows, the project incorporates channel benching at the OHWM to create an overflow floodplain, designed to enhance conveyance during storm events. These benches will be armored with grassed turf reinforcement mat (TRM) and reinforced with a riprap trench positioned just outside the OHWM limits for added stability, reducing disturbance of the natural channel bed across most of the reach. In addition, three detention basins within the project area will be cleared, excavated, and reshaped to restore their original capacity and improve stormwater management. Two basins are adjacent to the channel, while the third and largest basin receives flow from the channel at the downstream end of the reach.
This design prioritizes environmental stewardship by blending structural stability with nature-based techniques that minimize ecological impacts. The use of grassed TRM and riprap ensures slope stability while fostering vegetative growth, improving water quality, and supporting habitat restoration alongside effective flood mitigation.
