A Field Study of Green Roof Hydrologic and Water Quality Performance

摘要: Recent regulations intended to minimize the amount of nitrogen and phosphorus in stormwater runoff have resulted interest treatment practices reduce nutrient loadings. In ultra-urban areas where typical are not optimal because large surface area requirements, green roofs an option improve runoff. The hydrologic water quality performance two extensive eastern North Carolina's Neuse River basin were investigated. roof designs a flat 70 m2 with average media depth 75 mm, 3% pitch 27 100 mm. Extensive typically shallow depths (less than 150 mm) vegetation that requires minimal irrigation maintenance. Each retained significant (p < 0.05) proportion rainfall observed, 64% total measured at each site. Peak outflow was significantly reduced from (average peak flow reductions more 75% observed roof), substantially delayed On average, (TN) concentrations 2.7 mg L-1 higher (significant p 1.3 control outflow; TN amounts 0.02 g 0.12 lower outflow. (TP) 1 0.8 (both 0.05); TP 0.07 0.05 It determined media, composed 15% compost, leaching into This field study demonstrated importance selection locations removal is concern. Results this serve as benchmark for development contains fewer nutrients initially within mix, yet provides adequate plant growth.