Saturation to Improve Pollutant Retention in a Rain Garden

Saturation to Improve Pollutant Retention in a Rain Garden M I C H A E L E . D I E T Z * , † A N D J O H N C . C L A U S E N ‡ Nonpoint Education for Municipal Officials (NEMO), University of Connecticut, Middlesex Cooperative Extension Office, 1066... More

Saturation to Improve Pollutant Retention in a Rain Garden M I C H A E L E . D I E T Z * , † A N D J O H N C . C L A U S E N ‡ Nonpoint Education for Municipal Officials (NEMO), University of Connecticut, Middlesex Cooperative Extension Office, 1066 Saybrook Road, P. O. Box 70, Haddam, Connecticut 06438, and Department of Natural Resources Management and Engineering, University of Connecticut, 1376 Storrs Road, Unit 4087, Storrs, Connecticut 06269-4087 Rain gardens have been recommended as a best management practice to treat stormwater runoff. Replicate rain gardens were constructed in Haddam, CT, to treat roof runoff. The objective of this study was to assess whether the creation of a saturated zone in a rain garden improved retention of pollutants. The gardens were sized to store 2. 54 cm (1 in) of runoff. Results show high retention of flow; only 0. 8% overflowed. Overall, concentrations of nitrite+ nitrate-N, ammonia-N, and total-N (TN) in roof runoff were reduced significa Less