Stormdrains within the City of Aiken have been collecting and discharging stormwater runoff into Hitchcock Woods for decades. Directed and discharged into the Sand River at a high volume and velocity after every rain, the stormwater carves sand canyons in some spots and topples trees in others.
In the absence of any significant stormwater management alternatives, combined with the City of Aiken’s growth since 1950, the sheer volume and velocity of stormwater runoff being directed and discharged into the Woods has grown to a devastating level. One rain event discharged 35 million gallons of stormwater runoff into the Woods through a 10-foot-diameter pipe in a nine hour period, and at its peak, at a rate of 100,000 gallons per minute.
Damage to the Woods caused by urban stormwater runoff includes:
- Massive Erosion: Woods real estate is lost after every rain. An area once passable by foot has been eroded into a 70 foot high and 25 foot wide canyon. Other areas in the Woods are in danger of becoming canyons of this scale.
- Sedimentation: Silt and sediment from large-scale erosion has smothered and killed many bottomland hardwood trees and has filled in and destroyed wetlands in the Woods.
- Pollutants: Urban stormwater runoff picks up and flushes trash, chemicals, sediment, and bacteria into the Woods that is harmful to its health, ecology, and pristine beauty.
- Impeding management: Woods areas eroded from stormwater runoff are so fragile that invasive species cannot be mitigated in these areas until the damage ceases and healing can begin.
HOW WE HELPED
We prepared a plan to help the city overcome these stormwater challenges and take a step toward an achievable solution. McCormick Taylor provided project management and technical support to develop and implement various water resources projects and solutions to reduce the volume and velocity of stormwater discharges into Hitchcock Woods, with the primary focus on the Sand River Watershed.
During the development of the implementation plan, McCormick Taylor facilitated meetings of the Hitchcock Woods stormwater task force, which was comprised of elected officials, city staff, private citizens, and members of the Hitchcock Woods Foundation. The goal of the task force was to develop a shared solution to cease the destruction of the Sand River within the Hitchcock Woods.
We were also responsible for:
- Conducting technical evaluations to support planning and design related to stormwater best management practices and other related project concepts
- Conducting and overseeing field investigations, stormwater sampling, and stream flow monitoring
- Performing technical analyses, including hydrologic and hydraulic modeling, statistical analyses, water quality investigations, GIS mapping, and data management using the previous studies contracted by the city
McCormick Taylor prepared a Stormwater Implementation Plan that identified over 20 potential capital improvement projects that could be installed to reduce the destructive runoff into the Sand River. The implementation plan evaluated and ranked these sites, separating the proposed stormwater best management practices into four “packages.” Currently, McCormick Taylor has completed design on a project that will provide approximately 25 acre-feet of stormwater storage within the Sand River watershed throughout downtown Aiken, with construction commencing late summer 2021.