Evaluating the Hydrologic Benefits of a Bioswale in Brunswick County, North Carolina (NC), USA

Water

Karthik Narayanaswamy¹  RebeccaA. Purvis²  WilliamF. Hunt³  Susan Libes⁴  RyanJ. Winston⁵  MatthewS. Lauffer⁶  Andrew McDaniel⁶  Brian Lipscomb⁶ 

[1] AECOM, Morrisville, NC 27560, USA;Atkins Engineering SNC-Lavalin, Raleigh, NC 27609, USA;Department of Biological and Agricultural Engineering, North Carolina State University, Raleigh, NC 27695, USA;Department of Coastal and Marine Systems Science, Coastal Carolina University, Conway, SC 29528, USA;Department of Food, Agricultural, and Biological Engineering, Ohio State University, Columbus, OH 43210, USA;North Carolina Department of Transportation, Raleigh, NC 27610, USA;

关键词: bioretention;    bioswale;    hydrology;    runoff;    stormwater;   

DOI  :  10.3390/w11061291

来源: DOAJ

【 摘 要 】

Bioswales are a promising stormwater control measure (SCM) for roadway runoff management, but few studies have assessed performance on a field scale. A bioswale is a vegetated channel with underlying engineered media and a perforated underdrain to promote improved hydrologic and water quality treatment. A bioswale with a rip-rap lined forebay was constructed along state highway NC 211 in Bolivia, North Carolina, USA, and monitored for 12 months. Thirty-seven of the 39 monitored rain events exfiltrated into underlying soils, resulting in no appreciable overflow or underdrain volume. The bioswale completely exfiltrated a storm event of 86.1 mm. The one event to have underdrain-only flow was 4.8 mm. The largest and third-largest rainfall depth events (82.6 and 146 mm, respectively) had a large percentage (85%) of volume exfiltrated, but also had appreciable overflow and underdrain volumes exiting the bioswale, resulting in no peak flow mitigation. Overall, this bioswale design was able to capture and manage storms larger than the design storm (38 mm), showing the positive hydrologic performance that can be achieved by this bioswale. The high treatment capabilities were likely due to the high infiltration rate of the media and the underlying soil, longer forebay underlain with media, gravel detention layer with an underdrain, and shallow slope.

【 授权许可】

Unknown