Drainage Headwall Upgrades

The Alamance Community College parking lot located at the northwest side of the campus drains to the southern end of the parking lot and discharges through a concrete headwall into a rock-lined natural channel which empties into the Haw River downstream. The drainage headwall started leaking, which accelerated the soil erosion around the wall. In addition, the drainage channel has grown with vegetation and started eroding under the sidewalk next to the channel. The proposed scope of work included repairing the leaks in the headwall, installing short retaining wall next to the sidewalk, and repairing the drainage channel.

Atlas Engineering reviewed available as-builts and conducted a survey of the area around the drainage headwall to establish elevations and geometry of existing drainage channel. Atlas designed the short retaining wall, pointed on the drawings where to patch the headwall to prevent further leaks, and designed the drainage channel repair. Drainage channel repair included regrading the area, lining it with erosion control blankets, and covering with rip-rap rocks. Two types of erosion control blankets were used: 1) Non-biodegradable heavy duty blanket lined the area of drainage flow. 2) Biodegradable blankets at the rest of the area.

Atlas Engineering assisted ACC with the building, pre-construction meetings, and performed site visits during the construction. During the site visits, Atlas Engineering worked closely with concrete workers and landscaping crew to ensure the work has been done per design and client's satisfaction.