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Performance of Nitrogen-Removing Bioretention Systems for Control of Agricultural Runoff |
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| Authors: | Sarina J. Ergas Sukalyan Sengupta Ryan Siegel Arka Pandit Yifu Yao Xin Yuan |
| Affiliation: | 1Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of South Florida, 4202 E. Fowler Ave., ENB 118, Tampa, FL 33620 (corresponding author). E-mail: sergas@eng.usf.edu 2Professor, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Dartmouth, MA. E-mail: ssengupta@UMassD.Edu 3Environmental Engineer, Tighe & Bond, Westfield, MA 01085. E-mail: rlsiegel@tighebond.com 4Graduate Research Assistant, Georgia Institute of Technology, Atlanta, GA. E-mail: arka.pandit@gatech.edu 5Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Dartmouth, MA. E-mail: yifu.yao@gmail.com 6Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Amherst, MA. E-mail: xin@engin.umass.edu |
| Abstract: | This research evaluated nitrogen-removing bioretention systems for control of nutrients, organics, and solids in agricultural runoff. Pilot-scale experiments were conducted with bioretention systems incorporating aerobic nitrification and anoxic denitrification zones with sulfur or wood chips as denitrification substrates. Varying hydraulic loading rates (HLRs), influent concentrations, and wetting and drying periods were applied to the units during laboratory and two seasons of field tests with dairy farm runoff. Total N removal efficiencies greater than 88% were observed in both units with synthetic storm water. In first-season field tests, moderate removal efficiencies were observed for chemical oxygen demand (46%), suspended solids (69%), total phosphorous (TP) (66%), and total N (65%). During the second season, operational changes in the farm resulted in lower organic, solids, and nutrient loadings resulting in improved effluent quality, especially for suspended solids (81% removal) and total N (82% removal). The systems were not hydraulically overloaded even at 20 times the normal HLR. |
| Keywords: | Stormwater management Agriculture Nitrification Denitrification Sulfur Wood Runoff |