2016 journal article

Runoff and Pollutant Export from a LID Subdivision in North Carolina

JOURNAL OF ENVIRONMENTAL ENGINEERING, 142(1).

By: D. Line n & N. White*

co-author countries: United States of America 🇺🇸
Source: Web Of Science
Added: August 6, 2018

Storm rainfall on and runoff from a 3.35-ha low-impact development (LID) residential subdivision in the Piedmont region of North Carolina were monitored for 6+ years, which included predevelopment, during-development, and postdevelopment phases. Runoff was monitored and sampled at two stations using automated samplers. Along with residences, the drainage area to one of the stations (PC1) included an undisturbed wooded riparian buffer with level spreaders to distribute runoff, while the area to the other station (PC2) included four bioretention areas, permeable pavement, a roof runoff collection system, a detention pond, and other LID measures. Monitoring results documented that the postdevelopment, runoff to rainfall ratio, and pollutant export at both stations were significantly greater than those of the predevelopment phase, during which time the land use on the site was mature woods. The total nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS) export at both LID monitoring stations was 23 to 92% less than those from a nearby conventionally-developed subdivision monitored previously. These data indicated that LID subdivisions constructed on moderately to slowly permeable soils may not be able to maintain the runoff to rainfall ratio and TN, TP, and TSS export if the predevelopment land use was mature woods; however, if the predevelopment land use was cropland mixed with woods, then it may be possible to maintain predevelopment runoff to rainfall ratio and TN, TP, and TSS export. Further, the extensive use of LID techniques/measures in this residential subdivision resulted in less TN, TP, and TSS export compared to a similar conventional subdivision.